Science topic

Cell Line - Science topic

Established cell cultures that have the potential to propagate indefinitely.
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I am currently working on SK-N-SH cell line, nevertheless they are growing too slow while tried both in DMEM+10%FBS and RPMI+10FBS%. I split them 1-4 and 1-2 in DMEM and RPMI accordingly but they differentiated.
If anyone is working on SK-N-SH, please let me know the best growth medium and suggestions.
thank you
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SKNSH cells should be grown in EMEM (ATCC 30-2003, not DMEM with 10% serum.
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As a control i thought to use A549 Cell line. which is an alveolar epithelial cell line.Is that possible to use another cell line like mcf or normal lung epithelium as control group? why ?
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The A549 cell line though it is a pulmonary epithelial cell line derived from a human alveolar cell carcinoma, it is a genetically mutated human non-small cell lung cancer cell line. Although A549 cells exhibit some characteristics of AEC2s, their structural and barrier properties, as well as cell phenotypes, significantly differ from those of AEC2s, and they do not express pulmonary surfactant proteins that regulate surfactant function, structure, metabolism, and innate host defense under any culture condition. AEC2 are the prime stem cells in alveolar region during hemostasis and lung injury, their dysfunction is considered to play a leading role in the pathogenesis of Idiopathic Pulmonary Fibrosis.
Therefore, A549 cell line would not be an appropriate control for pulmonary fibrosis. A proper control is supposed to be the one that is the least variable, and A549 does not seem to fulfil this criterion. So, you should use a normal lung epithelium cell line as it would serve as a proper control. A control group is used as a benchmark or a point of comparison against which other test results are measured. A control group is critical as it helps ensure the internal validity of the study.
Best.
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In which culture medium MRC-5 cell line will have good growth?
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Thank you, I will keep in mind Malcolm Nobre
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I'm looking for the syngeneic cell line ENU1564 rat mammary adenocarcinoma cells. Does anyone have them, preferably in the USA, and are willing to share with me?
Thank you.
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Thank you very much Amos Bairoch for the information. I did contact Professor Stoica, who is now retired, and he reached to colleagues at his former institution, but unfortunately, they said they don't have those cells anymore :(
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I have a colony formation assay. I am seeding cells in a 96-well plate. The cell line is NTERA, 150 cells per well. I am seeding the cells with DMEM fortified with 10% FBS. Each well will have 200uL of this media. I will be incubating the treated cells for 14 days. I will be counting colonies on days 4, 7, 10, and 14.
How often should I remove the old media and replenish the wells with fresh media?
Thanks in advance.
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NTERA doubling time is actually 50-60 hours. Should I still go with 3-4days?
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Hello Dear all!
I would like to know if it is possible to have a stable cell line with a response element attached to a luciferase signal, also, Could it be possible to have in the same stable cell line a fluorescent protein that indicates the insertion within the genome of the before mentioned response elements/luciferase at the moment of generating it? (Have in mind that the plasmid used to generate the stable cell line confers a hygromycin B resistance to the cell line, after selection with this antibiotic)
if that is the case would it mean that when looking at the cells in a fluorescent microscope with a suitable laser exciting the fluorescent protein all the cells should exhibit fluorescence?
Thanks in advance for your help
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Yes, this is possible and is a strategy used in research. One of the examples I am familiar with is Plasmodium falciparum sporozoites that express both GFP and luciferase in order to track the parasite in different assays. A good description is available here:
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Are these 2 cell lines immortalized by a transgene or by nature?
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Insect cell lines, Sf9 and Sf21 are spontaneously immortalized cell lines with a species of origin Spodoptera frugiperda. The spontaneous immortalization of cells requires genomic instability, such as alterations in chromosomes, epigenetic changes and mutations in genes that occur during repeated cell division.
You may want to refer to the links below.
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Hi everyone. I am trying to set up an MTT assay with VCap cell line. I have previously given it a try based on a few research papers but I had a huge variation every time. Can anyone please help me with the number of cells to be used and the procedure to obtain consistent results?
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Thank you Malcolm Nobre for the detailed information. I will adjust the cell number according to your suggestion.
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It is the first time I want to grow this cell line. I thawed the cry-tube which was in nitrogen tank and then try to aspirate it with proper medium.The cells was not aspirated completely. Can you help me please?
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Hello,
Hope you are fine. You can aspirate your cell suspension for 4 or 5 times(with moderate rate). The cell suspension should be homogenous. If Some small particles remain, It's fine. You can use this suspension for growing cells.
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I am using IMR-32 cells as a neuroblastoma cell line model for MYCN amplified cells. This cell line has poor transfection efficiency. Using lipofectamine 3000 reagents, I am getting only about 30% efficiency for transfection. I am looking forward to the suggestions for increasing the transfection efficiency of IMR-32 to a higher-end.
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I have recently had good transfection efficiency with IMR-32 Cell Avalanche from EZ Biosystems. I first tested their suggested optimization protocol and then fine-tuned it. Good luck!
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Hi. We have been observing this strange cell death morphology during months. Cells die and acquire a "fried egg" morphology as it is shown in picture (A431 cell line). When it happens, all the cells die alike. It appears randomly in cell plates and not in all the experiments, but we are thinking that affected-wells distribution could be repeated, but it does not occur in all the plates. It has nothing to do with cell treatment, because it has been observed also in control cells. If you have some advice, please anwer :)
Thank you!
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Hi Neza, Hope you are doing well. I have been experiencing a very similar issue as you did two years ago - I plated U2OS cells in a 96 well format, and while obviously edges tend to have more random 'died well', sometimes the middle part can happen as well. I'm wondering if you have figured the problem out yet? Thank you very much!
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I am writing to report a concerning issue I've encountered during my recent migration assay using RAW 264.7 cells. I have followed the standard protocol, but I am facing a serious challenge with cell viability and scratch healing in response to CXCL9 treatment.
Here is a detailed description of the experiment:
Cell Line: RAW 264.7 cells
Media: DMEM Free Serum (used to standardize the results, Raw cells 264.7 grow in DMEM with 10%)
Scratch Assay Setup:
Cells were plated in 12-well plates until they reached confluence.
Media was removed, and cells were washed with PBS.
A scratch was made using a 200μl tip.
Cells were washed again with PBS.
Fresh DMEM Free Serum media containing varying doses of CXCL9 cytokines was added.
The issue I'm facing is that after the addition of CXCL9, the scratch disappears quickly and cells seem to detach and float, indicating a loss of cell viability.
I would like to inquire whether I am following the correct protocol, if a reduced FBS media is preferable over serum-free media, or if you have any alternative suggestions for conducting the migration assay with RAW cells.
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I have a feeling you are not following the right protocol. Maybe the protocol provided below will help.
1. After the cells are 90-95% confluent, remove the spent media and add 1ml of 5 µg/mL of mitomycin C (prepared in culture medium) to each well. Mitomycin C will stop proliferation of cells for 2-5 h before scratching. So, in a way, it will help to ensure true detection of migration. Incubate the plate for 2 h at 37 °C and at 5% CO2.
2. Remove the medium with mitomycin C and wash the wells once with 1ml of 1X PBS.
3. Add 1ml of 1X PBS and manually scratch the wells vertically with a 200µl yellow pipette tip. Use a new pipette tip for each well.
4. Remove the PBS and then add the media containing varying doses of CXCL9. Then proceed as usual with the assay.
It is important that you stop the proliferation of cells. Without mitomycin C treatment, I feel the proliferating cells may be occupying the area created by the scratch and due to over confluency, the cells may be detaching from the substratum and floating.
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If I am using the SHSY5Y cell line to test CNS regeneration, do I have to differentiate it to be more reliable?
if yes, what is the most reliable & applicable protocol?
Also, any hint on the specific CNS regeneration markers to be detected using this particular cell line?
Many thanks.
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Hi
No you have to keep the cells in differentiation media all the time until experimentation.
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I have developed an peptide with machine learning that targets receptors vegfr1, vegfr2, and vegfr3. I plan to test its binding specificity on each receptor and measure the downstream effects in a cell line
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Identifying a cell line that expresses VEGFR3 exclusively or with very low expression of VEGFR2 and VEGFR1 can be challenging, as many cell lines express multiple VEGF receptors. However, here are some approaches to help you identify suitable cell lines:
  1. Cell surface protein expression analysis: Use flow cytometry or fluorescence microscopy to analyze the cell surface expression of VEGFR1, VEGFR2, and VEGFR3 in various cell lines. This will help you identify cell lines with high expression of VEGFR3 and low expression of VEGFR1 and VEGFR2.
  2. qRT-PCR analysis: Perform quantitative reverse transcription polymerase chain reaction (qRT-PCR) to evaluate the mRNA expression levels of VEGFR1, VEGFR2, and VEGFR3 in different cell lines. This will give you an idea about the relative expression levels of these receptors in each cell line.
  3. Database mining: Utilize online databases such as ArrayExpress, Gene Expression Omnibus (GEO), or Cancer Cell Line Encyclopedia (CCLE) to explore gene expression profiles of various cell lines. You can use tools like GEO2R or limma to compare the expression levels of VEGFR1, VEGFR2, and VEGFR3 across different cell lines.
  4. Knockdown or knockout experiments: Consider performing knockdown or knockout experiments using CRISPR-Cas9 or shRNAs to specifically silence VEGFR1 and VEGFR2 in cell lines that express these receptors. This will allow you to evaluate the effect of VEGFR3 expression in the absence of VEGFR1 and VEGFR2.
  5. Use cell lines with known VEGF-A/VEGFR interactions: Some cancer cell lines, such as HUVEC (human umbilical vein endothelial cells) and HMVEC (human microvascular endothelial cells), are known to express high levels of VEGFR3 and have been shown to interact with VEGF-A. You may also consider using cell lines that have been engineered to overexpress VEGFR3.
  6. Screening assays: Develop or utilize existing screening assays that measure the binding affinity of your peptide to VEGFR1, VEGFR2, and VEGFR3. This will enable you to identify cell lines with high binding affinity for your peptide, indicating strong expression of VEGFR3 and potentially low expression of VEGFR1 and VEGFR2.
  7. Combinatorial approaches: Combine the above approaches to increase the confidence in identifying cell lines that meet your criteria. For example, you could first narrow down your options by analyzing gene expression profiles from online databases, followed by validating the expression levels using qRT-PCR or flow cytometry.
  8. Validation with orthogonal methods: Once you have identified potential cell lines, validate their expression profiles using orthogonal methods such as western blotting or immunofluorescence staining. This will provide further confirmation of VEGFR expression levels and help rule out any discrepancies due to technical variations.
  9. Test your peptide: Finally, test the binding specificity of your peptide on the shortlisted cell lines using techniques such as flow cytometry, immunoprecipitation, or surface plasmon resonance. This will help you determine the most suitable cell line(s) for your studies.
Remember that it is crucial to carefully evaluate and validate the expression profiles of VEGFR1, VEGFR2, and VEGFR3 in the selected cell lines to ensure the accuracy and reliability of your results.
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Hey all
I tried reviving the HaCaT cell line using the standard protocol for cell revival. However, they aren't attached to the flask even after 72 hours. The cell lines were stored in August 2022 by a colleague of mine. What would be the reason behind their failure to revive?
Media used: DMEM HG 12% FBS
The recommended media by ATCC for culturing HaCaT is Dermal Cell Basal Medium (https://www.atcc.org/products/pcs-200-011#required-products). However, our lab has previously grown and cultivated them in DMEM with 12% FBS. Others have used DMEM with 5% FBS. (
Could the problem be due to the difference in media? Or the stress due to storage conditions that prevented its revival?
Are these HaCaT cells stored in -80 really lost?
Please have a look at the image.
Thank you
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V H Krishna Prasad No, calcium ions can affect cell adhesion.
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We are interested in purchasing the 38C13 cell line, anyone know where we can get these cells?
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May I know where did you get the cell line?
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I've cultured cells (cell lines) "stored for a long period in liquid nitrogen".
In addition to low viability, I have a problem with cell attachment to the culture flask (most cells are still in suspension), and some of them form spheroids. How to save cells that are still alive :
- Could long storage of cells cause this problem?
- Are there factors that promote cell adhesion?
- It is possible to use 3d cell culture in this case?
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A. Could long storage of cells cause this problem?
No, cells may be stored in liquid nitrogen for years (> 10 years) without any decrease in viability unless you have been late to refill the liquid nitrogen tank from time to time. If you notice low viability after thawing the cells stored in liquid nitrogen, then there may be other factors that you would need to investigate.
1. Have you cryopreserved the cells in an appropriate freezing medium and using the gradual freezing technique (i.e., -1 degree C/min) with the help of Mr. Frosty container? This container is designed to achieve a rate of cooling very close to -1°C/minute, the optimal rate for cell preservation. This will help to maintain the viability.
2. Have you thawed the frozen cells rapidly (< 1 minute) in a 37°C water bath? This too will preserve the viability of cells.
3. If yes, then you may have to consider environmental stress as a possibility, and what could cause environmental stress?
Look out for contamination, temperature fluctuation, improper gas mixture in the environment, inappropriate substratum for cell attachment (are you using tissue culture treated flask?) and inadequate or altered nutrients in the culture media.
B. Are there factors that promote cell adhesion?
Yes, serum contains adhesion-promoting factors, You may increase the amount of serum from the normal (10%) to 15% in the culture media as mentioned by V H Krishna Prasad .
C. It is possible to use 3D cell culture in this case?
I would suggest you first get the 2D cell culture in place.
How to save cells that are still alive?
Centrifuge the cell suspension at low speed (800 rpm for 5 mins). Resuspend the cell pellet in a small volume of culture media containing 15% FBS. Seed the cells in a smaller vessel (say in a well of a 6-well plate or in a 35mm petri dish).
Hope it works!
Best.
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I used HEK293 cells as expression system, transiently transfected using PEI. Harvested on Day 4 or sometimes Day 5. The enzyme produced always show up as strong band in cell pellet in western blot , while there is no band in supernatant. While doing enzyme assay, this shows no activity.
I changed my expression system and used Expi293 cell line, which produces an active enzyme.
My questions:
1. Is this related to cell lines, but in past we have seen HEK293 cell line producing any other enzymes?
2. Does vector design plays any role in this?
Iram
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Expi293 cell lines
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Hey all my cell culture fellows,
i need your help and experience...
i am trying to establish a cell line in our lab. i bought a fish cell line and i am now trying to get it startet. But it is not going as well as i hoped. The epithelial like cells are growing at 19°C with no extra CO2. I got about 1 Million cells delivered and i tried to seed them into a 25cm^2 flask, as statet in the protokoll. at first they seemed to grow fine, but in the last passage and i the passage now, the cells are distributed very unevenly in the flask. Last passage, the cells were very dense in the upper half of the flask (like if you watch the field under the mikroskop), and in the lower half, they were not as dense. And around the edges there were almost no cells growing.
In this passage, i have a small field in the middle of the flask where the cells are very dense, and around that they are not growing well. Also today on day five i have a lot of cells detached. Its very frustrating... i thought maybe the incubator is not standing right, but the distribution of the cells make no sense to me...
Has anyone any ideas?
Thank you!
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Hey!
I am not sure if this will work for you or not, but in general, whenever I seed cells(be it primary or a cell line) I always move my flask in the shape of the number 8 (Keeping this in mind: be gentle ). This will distribute your cells uniformly throughout the flask.
You can also try coating your culture flask first as per your cell requirement. This will help with the proper adherence of cells.
Avoid moving your flask too quickly or doing harsh pipetting.
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Hello Scientist.
I am currently doing qPCR to detect apoptotic gene expression in cell lines. After incubation with treatment, do i need to collect both dead and live cells OR only live cells to proceed with RNA extraction & qPCR?
Thank you in advance.
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Hello, For qPCR to find apoptotic gene activity, it is recommended to collect only live cells. This is because apoptotic cells may have degraded RNA, which can affect the accuracy of the qPCR results.
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I want to study the expression of some proteins related to oxidative stress with western blot. I wonder what microglia cell line is the best for it.
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If you want to correlate the data with humans, HMC-3 cells would be better to study oxidative stress and inflammation.
Please find the attached paper to know in detail.
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Dear All,
I am a third year PhD student and have previously optimized a protein complemetation assay (PCA) using NanoBit technology for a high throughput drug screening. I have further validated the activity of the compounds through the assessment of downstream inflammation. However, I need to validate the PCA assay further to prove that my compounds are not interacting with the NanoLuc fragments. The initial plan was to create an NanoLuc-CyOFP HEK293T cell line and carry out the PCA with my compounds using that. However, I have been doing some research and I am worried that "components of the NanoBit optimized reporter are structurally distinct from Nanoluc" see
Will doing this further assay then not validate the compounds are not interacting with the NanoLuc fragments in the initial assay?
(Further to this, I know that a better assay would be using the same NanoBit technology with a different well known protein-complex from a different pathway, however, due to lack of time and resource I am unable to do this)
Any clarification or explanation would be appreciated.
Thank you in advance.
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You're welcome! I'm glad I could help. Good luck!
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Dear friends
How to detect Asparaginase resistant cell lines? Do you know cell lines resistant to asparaginase? Is there any protocol to detect the resistance?
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Methods to identify Asparaginase-resistant cell lines, including:
  1. MTT Assay: This assay measures the ability of cells to convert MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) into formazan crystals, which indicates cell viability. Treat Asparaginase-exposed cells with MTT, and then solubilize the resulting formazan crystals with DMSO. Measure absorbance at 570 nm to determine cell viability. Resistant cell lines will exhibit higher viability compared to sensitive ones.
  2. Trypan Blue Exclusion Assay: This assay evaluates cell membrane integrity, which is compromised in dead cells. After exposure to Asparaginase, stain cells with Trypan Blue (0.4% w/v), and then count live cells using a hemocytometer or automated cell counter. Compare the number of live cells between control and treated groups to determine resistance.
  3. Flow Cytometry Analysis: Utilize flow cytometry to evaluate changes in cell surface markers or apoptotic markers after Asparaginase treatment. Annexin V-FITC and Propidium Iodide (PI) staining can help differentiate between early apoptotic (Annexin V+/PI-) and late apoptotic/necrotic (Annexin V+/PI+) cells. Compare the distribution of cell populations between control and treated samples to identify resistance.
  4. Cell Death Detection Kit (ELISA): Measure caspase-3/7 activity using a commercial kit (e.g., Caspase-Glo® 3/7 Assay). This assay quantifies the amount of active caspase-3/7, an executioner protease involved in apoptosis. Compared to sensitive cell lines, resistant cell lines typically display reduced caspase-3/7 activation upon Asparaginase treatment.
  5. Real-Time PCR and Western Blot Analyses: Evaluate mRNA and protein expression levels of genes related to Asparaginase resistance, such as ASNS (asparagine synthetase), GLUL (glutamine synthetase), or ASS1 (argininosuccinate synthetase 1). Resistant cell lines often upregulate these genes to maintain intracellular asparagine levels.
  6. Clonogenic Survival Assay: Seed cells in agarose gel and allow them to form colonies before treating them with Asparaginase. The surviving fraction represents the population of resistant cells. Repeat the process several times to generate a dose-response curve and calculate the IC50 value, which reflects the concentration of Asparaginase required to inhibit colony formation by 50%. Compare the IC50 values between control and resistant cell lines.
  7. Xenograft Model: Establish xenograft models using cell lines in immunodeficient mice. Monitor tumor growth and response to Asparaginase treatment. Measure tumor volume, and compare the efficacy of Asparaginase in shrinking tumors between control and resistant cell lines.
  8. High-Throughput Screening (HTS): Perform HTS using a large panel of cell lines to identify those that exhibit resistance to Asparaginase. Employ automated platforms like liquid handling systems or microfluidics to efficiently screen numerous cell lines under standardized conditions.
Some known Asparaginase-resistant cell lines include:
  • Jurkat cells (acute lymphoblastic leukemia; TALL-104 cell line)
  • K562 cells (chronic myeloid leukemia; BCRC-00562 cell line)
  • HL-60 cells (promyelocytic leukemia; CRL-5967 cell line)
  • U937 cells (myeloid leukemia; CRL-1593.2 cell line)
  • THP-1 cells (monocytic leukemia; TIB-202 cell line)
All the best with your research
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hello i am a new master's student in an immunology lab and I have been assigned a topic to establish a stable cell line for swine interleukin 2 gene expression, but I do not know how to start my experiment, if someone can help me in this I will be highly obliged. Thanks
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It's a very fundamental question. First, a appropriate cell line is essential for constructing a stable transgenic cell line. According to the cell line, an efficient method to transfer gene to the cell line is need, such as expression plasmid, lentivirus. Finally, the cell lines that stably expressed swine interleukin 2 can be obtained after a series of screening.
An article may be helpful as follow.
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Hello guy, I need your help to solve my problem in experiment. I got sample as culture cell line. I have to detect whether virus infection or not in this cell culture sample (pharmaceutics product). I should test the presence or not of RNA virus from bovine/porcine in these cell lines by quantitative real-time PCR method.
My plan is: I will find the specific sequence for these RNA viruses to design primer, probe and plasmid (that I will use as positive control when I running RT-qPCR, and make standard curve). In this case, when I perform RT-qPCR I need RNA or DNA to running.
My question here is: In this case, how can I isolate RNA or DNA of virus from culture cells? Or anyone have experience to perform this kind of experiment before can tell me what should I do in this case?
I have never do this kind of experiment before so I am so confused. Thank you so much for your help.
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The safest way is to use commercial kits such as "MagMAX Viral and Pathogen Nucleic Acid Isolation Kits (RUO)". For example, this kit has been used for the isolation of SARS-CoV-2 and other infectious disease pathogens.
The other well-known method is Phenol-chloroform extraction (see details below):
Materials and Reagents:
  • Virally infected cell culture
  • Cell culture media and reagents
  • Phosphate-buffered saline (PBS)
  • Cell scraper or trypsin
  • Centrifuge
  • Lysis buffer (proteinase K, SDS, EDTA)
  • Phenol-chloroform-isoamyl alcohol
  • Chloroform
  • Ethanol
  • DNA precipitation reagents (e.g., isopropanol, sodium acetate)
  • 70% ethanol
  • TE buffer (Tris-EDTA) or other suitable DNA storage buffer
Procedure:
  1. Harvest Cells: Grow the virally infected cells in a suitable cell culture medium until they reach the desired level of infection. Harvest the cells when they exhibit cytopathic effects or sufficient virus production.
  2. Cell Lysis: a. If using adherent cells, carefully remove the culture medium and wash the cells with PBS. b. Detach the cells using a cell scraper or trypsin (if adherent) and transfer them to a centrifuge tube. c. Pellet the cells by centrifugation and discard the supernatant.
  3. DNA Extraction: a. Resuspend the cell pellet in lysis buffer containing proteinase K, SDS, and EDTA. Incubate at an appropriate temperature (usually 55-65°C) for several hours or overnight to lyse the cells and degrade cellular proteins. b. After lysis, perform phenol-chloroform-isoamyl alcohol extraction to separate the aqueous DNA-containing phase from the organic phase. Centrifuge to separate the phases. c. Transfer the aqueous phase to a new tube and perform a chloroform extraction to further purify the DNA. d. Precipitate the DNA by adding isopropanol or another DNA precipitation reagent along with sodium acetate. Centrifuge to pellet the DNA.
  4. DNA Washing: a. Carefully remove the supernatant and wash the DNA pellet with cold 70% ethanol. Centrifuge and discard the ethanol. b. Air-dry the DNA pellet briefly or use a vacuum concentrator to remove residual ethanol.
  5. DNA Resuspension: a. Once the DNA pellet is dry, resuspend it in an appropriate volume of TE buffer or other DNA storage buffer. The concentration and volume will depend on your downstream applications.
  6. Quality Control: a. Quantify the extracted DNA using a spectrophotometer (UV absorption at 260 nm) and assess the quality by checking the 260/280 nm and 260/230 nm ratios. Pure DNA has ratios around 1.8-2.0 for both ratios.
  7. Storage: a. Store the isolated DNA at -20°C or -80°C for long-term use. Avoid repeated freeze-thaw cycles.
Remember that the specific protocol may vary based on the virus you're working with, the cell type you're using, and the DNA extraction kit or reagents you prefer. Always follow biosafety guidelines and precautions when working with viral samples, and adapt the protocol to your specific needs and conditions.
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I am currently establishing a transgenic cell line (H9) using a plasmid containing Zeocin resistant gene. An antibiotic kill curve was performed ranging from 0.5 ug/mL to 1000 ug/mL. H9 WT cells were killed within 2 days with the lowest concentration (0.5 and 1.0 ug/mL), while all cells detached and underwent cell death within a day with other concentration. Similar rate of cell death was observed in cells containing the resistant gene where its gene expression is driven by SV40 promoter.
Therefore, I am asking if anyone has used Zeocin to maintain or select cells with Zeocin antibiotic. If yes, what is the concentration used, particularly on H9 cell lines.
Thank you.
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The use of Zeocin resistance genes is relatively limited. It is necessary to set a gradient concentration to treat cells, and it is generally advisable for all cells to die within about 10 days. Suggest checking other literature or consulting technical personnel.
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The dose is standardised in animals in mg/kg.
i just wanna extend the same treatment to cell lines and was trying to find a way to convert Drug dose from mg/kg to mg/ml ?
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The Article shared by Rafik really helped. I am grateful for this.
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Hello!
I have worked with many cancer lines that carry various mutations and gene rearrangements. But now I have a question - are there stable (or, with a lifespan limited by the natural Hayflick limit) cell lines derived from patients with, for example, Down syndrome or Shereshevsky-Turner syndrome?
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Yes, there is the human fibroblasts Detroit -532 (a human Down syndrome cell line, ATCC CCL-54).
You may maintain this cell line in DMEM High glucose supplemented with 10 % FBS and 1 % non-essential amino acids.
FYI: A longevity study performed by ATCC showed that the depositor's material was capable of growing for an additional 28 population doublings (i.e., unknown + 28) before the onset of senescence.
Best.
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Hi,
I am generating stable cell lines (HEK293A) with my gene of interest using the AAVS1 integration system. The integration site is present on Chromosome 13, which is triploid in HEK cells. I want to confirm how many copies of my gene of interest are present in the different clones I have got for my stable cell lines. One way of doing so is doing a qPCR on genomic DNA isolated from these cells but what control should I be using to estimate the copy number?
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Possible but you would then need to calculate the number of plasmids per mass of plasmid DNA.
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Hello
have a good time
My goal is to transfect SH-SY5Y and U87-MG cell lines using electroporation method. Has anyone had experience working with these cell lines? And what electroporation buffer should I use to transfect these?
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I read somewhere about mannitol based buffer as an efficient one
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There is a SA13 human hybridoma cell line in our lab, which - according to the rules of working with cells - is grown on a special IMDM medium. We do not have the opportunity to obtain this medium, but there are DMEM, RPMI, EMEM, alphaMEM media. Can I replace the IMDM with the ones above? Is there a critical difference?
Thanks in advance!
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IMDM is a modification of DMEM containing additional amino acids, vitamins, selenium and HEPES buffer, and is formulated with potassium nitrate in place of ferric nitrate. It is used for a variety of hybrid cells. I am attaching the formulations for both IMDM and DMEM. You may compare yourself and find the difference between the two. I would suggest you go for IMDM.
IMDM
DMEM
Best.
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Is there a human neuronal cell line used as an in vitro model to apply scratch injury to perform cell migration assay?
Other than SHSY5Y as I am using it already.
If any, any special hints about its culture protocol?
Thanks.
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If your study involved studying neuronal repair and the signaling mechanisms mediating neuronal repair and neurite growth, it is recommended to perform the experiment in differentiated neuronal cells.
SHSY5Y cells can be differentiated using 10uM RA in reduced serum (2% FBS) media for 7 days.
Thanks,
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I want to perform an antiviral assay for HIV inhibitors. I can't do the p-24 assay and I can only do the beta-galactosidase assay. So which cell lines can I use for this other than the tz-mbl cell?
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Dear Sarita Swain , in the past i made several experiments with HeLa-CD4-LTR-beta-gal cells (so called MAGI) or MAGIC5 cells ( MAGI-derived, CCR5-expressing cells ). Are there any details you could provide ? Good luck :)
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I extracted RNA from two different types of cell lines: one that is sensitive to cisplatin and one that is resistant. I then followed the cDNA synthesis protocol and observed a strong band for the resistant cell line cDNA, but no band for the sensitive cell line. Can you help me identify the problem?
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Possible reasons include: low RNA quality or concentration, the presence of inhibitors or contaminants, inappropriate priming strategy, issues with the reverse transcriptase enzyme, suboptimal reaction conditions, or RNA molecules' integrity and size.
So you should check the RNA quality and concentration, consider purification steps if needed, verify the priming strategy, and ensure proper storage and functionality of the reverse transcriptase. Optimization of reaction conditions may also be necessary. Running positive control reactions can also help pinpoint the problem.
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I had SH-SY-5Y cell line that was contaminated however I managed to decontaminate it using antibiotic and it worked and ended up having a good stock of the cell line with high proliferation and viability however when I tried to seed 7500 cells per well in a 96 well plate after 24 hours cells started to settle and take the morphology but once I started treatment with a drug when the media was aspired and new media with drug was added cells started to detach from the well forming batches, I tried different cell counts with different confluency and from different passages but the problem was still there
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Maybe you have selected for a less adhesive sub-population during your selection process? As far as I can recall SH-SY-5Y cells exhibit a mixed phenotype in culture?
Does detachment also occur when you just change the media and don't add your drug?
Best,
Christian
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I never handle the SHSY5Y cell line before, so it is a new thing for me, as far as I observed for these past five days, their growth is really slow. Is it normal? I use the complete media of nutrient mixture F12 Ham supplemented with 15% FBS (recommendation from ECACC), I'm afraid if there might be something I missed or if there is any recommended suggestion for me. Thank you.
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They are very slow growing with a doubling time of ~70 hours, which is very much slower than most tumor cell lines I know.
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I have been growing SH-SY5Y cell line in DMEM/F12 media supplemented with 15% heat-inactivated FBS. For differentiation, I plated 10000 cells per well in 96 well plates and changed media every day, which contained 3% FBS with 10 micromoles RA, and also I have tried with 10% FBS and 10 micromoles RA.
In 3% FBS, I noticed cell death within two days of differentiation, and in 10% FBS after five days the well was almost filled with cells. So what should be the ideal FBS concentration and seeding density for differentiation?
I have attached image of the SH-SY5Y cell line acquired after 5 days of differentiation with 10% FBS and 10 micromoles RA most of the cells look like epithelial
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Thank you Julián Gerardo Bonetto for your kind suggestion
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Dear colleagues,
I would like to assess in vitro the cytotoxic effect and possible Bruton kinase inhibition of a serries of organic compounds as potential therapeutics for the treatment of chronic lymphoblast leukemia.
Could I use K 562 cell line as a model? Could you suggest a more suitable cell model? Thank you!
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Maya Guncheva, you're welcome!
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Looking to buy a rabbit B cell line for purchase, are there any available?
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As of my knowledge, B cell lines are typically established from human, mouse, and rat sources due to their common usage in immunological research. Rabbit B cells are often used in the production of polyclonal antibodies, but these cells are typically not immortalized into cell lines.
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I have fixed my cell (U937 cell line) using 4 % parafarmaldehyde and blocked them using 1%BSA. Can I still use TritonX100 to permealize the cell?
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Thank you very much Saif and Yannick.
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Want to know how transfection of mutants in cell lines can be performed in effective manner? Any detailed protocol which would be cheap and easy to perform kindly suggest.
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Using calcium phosphate nanoparticles can be a cheap way if electroporation is not an option.
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Hi all, I am interested in performing bulk RNA sequencing on primary human cells that have been cultured in absence/presence of certain types of drugs. I know n=6 is quoted as an acceptable number for cell lines and genetically identical mouse samples, but I can imagine the number of replicates needs to be higher when using primary human cells taken from a variety of donors. I am struggling to find any comparable published studies so I was wondering if anyone here had an idea/some experience with this? Many thanks!
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For RNA-seq it largely depends on the effect size you are hoping to resolve. I've found that Table 1 in the following paper to be helpful here:
So to call a fold change of 2 statistically significant 98% of the time, do N=5 with 30M reads per sub-library.
As the table points out, it also depends on your sequencing depth which gives you more or less confidence.
For your case if you are also concerned about large variance between replicates, you could do pre-NGS qPCR validation of a couple genes you are interested in to gauge the dispersion between replicates and between treatment groups.
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I recently thawed THP-1 cells frozen at passage 20 in 2016 in 10% RPMI. After thawing, the cells appeared to recover successfully, and the next day I changed the media to remove the remaining DMSO. The cells were cultured in T-25.
On the 7thday, the two T-25 flasks showed turbid media. The other cells in the CO2 incubator with the THP-1 cells did not exhibit any additional contamination.
A microscopic examination revealed tiny critters that were moving quickly.
I suspect it might have been the frozen cell vial that was the contamination source.
Since I have been working with various cell lines, I have never seen anything like this!
Any suggestions as to what this might be, and how to get rid of it, would be of great help!
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@all Based on your description, it is likely that your THP-1 cell culture has been contaminated with a microbial organism. The presence of tiny critters moving quickly suggests a possible contamination by microorganisms, such as bacteria or protozoa. Here are some steps you can take to address the contamination issue:
  1. Quarantine the contaminated culture: Remove the contaminated T-25 flasks from the incubator and isolate them from other cell cultures to prevent further contamination.
  2. Confirm the nature of contamination: Perform a Gram stain or other suitable staining technique to identify the nature of the contaminants. This will help determine whether they are bacteria, protozoa, or other microorganisms.
  3. Clean and disinfect the incubator: Thoroughly clean and disinfect the CO2 incubator to prevent the spread of contamination to other cultures. Follow the manufacturer's guidelines for disinfection and decontamination procedures.
  4. Discard contaminated cells and media: Dispose of the contaminated cells and media properly. It is essential to handle biological waste according to the regulations and guidelines established by your institution or laboratory.
  5. Restart the culture from a reliable source: Obtain a fresh vial of THP-1 cells from a trusted source, preferably a well-characterized cell bank. Thaw the new vial following the appropriate protocols and establish a new culture.
  6. Practice aseptic techniques: Ensure that you are maintaining strict aseptic techniques during cell culture handling. This includes working in a clean laminar flow hood, using sterile equipment and reagents, and regularly disinfecting the work surfaces.
  7. Monitor the new culture for contamination: Regularly monitor the new THP-1 cell culture for signs of contamination. Perform regular microscopic examinations and maintain a vigilant eye for any changes in cell morphology, turbidity, or other signs of contamination.
If the contamination issue persists, it may be helpful to consult with a cell culture expert or the technical support team at your cell culture reagent supplier for further guidance and troubleshooting specific to THP-1 cells.
Remember, preventing contamination in cell culture requires attention to detail, proper aseptic techniques, and a clean working environment. Regularly reviewing and updating your cell culture protocols can help minimize the risk of contamination and ensure successful experiments.
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I am now trying to work with OSU-CLL cell line. Oddly, after a while of culturing (perhaps we changed the FBS), the cell started to exhibit some behavior like an adherent cell. They like to clump togehter and sink to the bottom of the culture flask, is this normal? Do you have any experience with culturing this cell line?
Thank you very much for your help!!
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Hi Lyu
Do they differentiate into other cells like THP-1 cells which may lead to their adherence?
Possibly, your cells may have a small population of cells that are expressing the adhesion proteins leading to their attachment.
Thanks
Vikrant
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The cell line I used in my experiment is a self-cultured porpoise fibroblast cell line. On the first day, I seeded cells on a 96-well plate and the cell density was 5 x 10^4 cells/mL. The day after, I added drugs and went for 24hr incubation. Then, on the third day, when I was going to perform the MTS assay, I found that all the cells were dead, including the cells of the control group which were only treated with a culture medium without any added drugs. I am so puzzled and wondering why, anyone has faced the same problem and can help me.
My cell culture medium is also without FBS since I need to collect the supernatant for the DNA damage assay. The number of passages of the cell line is 19. The cells cultured in T75 flasks were growing well and a little fast than before. Some people said that it is not good if cells grow too fast, is that true? Could this be the reason for the sudden death of my cells?
Thank you so much!!!!!!
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Thank you so much for your useful answer!
Actually, I did observe that cell size increased with passage increase. I will check it again.
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Hello everyone,
Is there anyone working with lipid-based nanoparticles (LPNs) for mRNA delivery who can share their thoughts?
Currently, I am working with PLGA:DOPE:DOTAP nanoparticles, but I am facing significant difficulties in achieving successful transfection in various cell lines (HEPG2, HEK293, JurkatE61). I have already attempted mRNA encapsulation and adsorption, but none of the formulations have yielded any transfection results.
I would greatly appreciate any insights or suggestions on improving the transfection efficiency with LPNs and mRNA delivery in these cell lines.
Thank you in advance for your assistance.
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Dear Junjie,
Yes, I did tested with Lip0 3000 and it works perfectly. So the problem is when I try to trasnfect with the hybrid particles in which I have tried either adsorbed or encapsulated mRNA and none have worked.
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Dear all,
My lab has just recently got a cell line. The cells grow a bit slowly and the medium color is changing quite fast from pink to orange compared to other cell lines. In addition, we observed some strange black debris. However apparently the movement is brownian, unlike bacterial movement.
Have you ever experienced thing like this? Could you help me pinpoint what is this debris and share any suggestion what should I do? Thank you.
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Hello all, thanks for all suggestions and discussion Mohammad Mahdi Heidari Justin Clark . Rashmi Trivedi we didn't use a cell scraper. Rebecca Miller in the end, we weren't able to pinpoint the root cause (have tried changing the media as well), so we use the cell from another batch of source. Since the cell growth was slow, we were also thinking if this might come from a "cluster" of dead cell organelles.
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I have a problem with number of cells in E0771 cell line . I usually use 100-2000 cells for sphere but I couldn't get good sphere.
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From an early age I knew the phrase "Let's Bind Swords to Swords", I knew this sculpture well. And I was not alone. And I think that there will come a time when "they shall bind their swords to ploughshares, and their spears to sickles: the people shall not lift up swords against the people, neither shall they learn to fight any more".
"Let's Bind Swords to Swords" is a bronze sculpture by artist Evgeny Vuchetich (1908 - 1974). Vuchetich was a highly regarded Soviet sculptor and artist, well known for his heroic monuments. In 1959, he received the award "People's Artist of the USSR".
The sculpture depicts the figure of a man holding a hammer high above his head in one hand and a sword in the other, forging the sword into an orale, a tool for cultivating soil for crops. This action symbolises man's desire to put an end to warfare and turn destructive tools into instruments for the good of mankind.
The book of Isaiah contains the following paragraph: "They shall turn their swords into pliers, and their spears into sickles: they shall not lift up sword against nation, neither shall they learn war any more."
This sculpture was presented to the UN as a gift from the USSR on 4 December 1959. On behalf of the Soviet delegation, the sculpture was handed over by Vasily V. Kuznetsov, First Deputy Minister of Foreign Affairs of the USSR, and on behalf of the UN, Secretary General Dag Hammarskjöld accepted the sculpture.
"Let's Bind Swords to Swords" is a bronze sculpture by artist Evgeny Vuchetich (1908 - 1974). Vuchetich was a highly regarded Soviet sculptor and artist, well known for his heroic monuments. In 1959, he received the award "People's Artist of the USSR".
The sculpture depicts the figure of a man holding a hammer high above his head in one hand and a sword in the other, forging the sword into an orale, a tool for cultivating soil for crops. This action symbolises man's desire to put an end to warfare and turn destructive tools into instruments for the good of mankind.
The book of Isaiah contains the following paragraph: "They shall turn their swords into pliers, and their spears into sickles: they shall not lift up sword against nation, neither shall they learn war any more."
This sculpture was presented to the UN as a gift from the USSR on 4 December 1959. On behalf of the Soviet delegation, the sculpture was handed over by Vasily V. Kuznetsov, First Deputy Minister of Foreign Affairs of the USSR, and on behalf of the UN, Secretary General Dag Hammarskjöld accepted the sculpture.
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I'll start working with kg1a cells. after the cell passage, the apoptotic occupations are not removed, gradually their number in the environment increases and they cause problems. How could you get rid of the apoptotic occupations?
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let the cells into 0.5% PBS as programed cell death after that they wil be grown well like kids. gg@saewon1
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Hello,
Does anyone have information about the ploidy of HT22 mouse hippocampal? I couldn't find anything about in the literature.
Thanks!
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The ploidy of the HT22 cell line, derived from mouse hippocampal neurons, is not widely reported in the literature. It is possible that the specific ploidy information for HT22 cells has not been extensively characterized or published.
The ploidy of a cell line refers to the number of sets of chromosomes it possesses. Most commonly, cell lines are characterized as either diploid (containing two sets of chromosomes) or aneuploid (having an abnormal number of chromosomes). However, to determine the precise ploidy of a specific cell line, further investigation and experimental analysis would be required.
If you need to determine the ploidy of HT22 cells for your research purposes, you may consider performing karyotyping or flow cytometry analysis. These techniques can provide information about the chromosome number and ploidy status of the cell line. Alternatively, you could contact the repository or laboratory from which the HT22 cells were obtained, as they may have additional information about the cell line's ploidy.
All the best
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I'll start working with kg1a cells. after the cell passage, the apoptotic occupations are not removed, gradually their number in the environment increases and they cause problems. How could you get rid of the apoptotic occupations?
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If you are observing a buildup of apoptotic cells after cell passage in your KG1a cell line, there are several steps you can take to remove them and maintain a healthy culture:
  1. Gentle centrifugation: After cell passage, you can try a gentle centrifugation step to remove the apoptotic cells. Centrifuge the cell suspension at a low speed (e.g., 200-300 x g) for a short duration (e.g., 5 minutes). This should pellet the healthy cells at the bottom while leaving behind the apoptotic cells in the supernatant. Carefully remove the supernatant without disturbing the cell pellet, and then resuspend the cells in fresh culture medium.
  2. Differential adhesion: Another approach is to utilize the differential adhesion property of healthy and apoptotic cells. Allow the cell suspension to settle in a culture dish or flask for a short period (e.g., 30 minutes to 1 hour). During this time, healthy cells will adhere to the surface, while apoptotic cells will remain in the suspension. Carefully aspirate the supernatant containing the apoptotic cells and replace it with fresh medium.
  3. Filtration: If the apoptotic cells are relatively larger in size compared to healthy cells, you can consider filtering the cell suspension through a cell strainer or a mesh filter with an appropriate pore size. This will retain the healthy cells while allowing the apoptotic cells to pass through, effectively removing them from the culture.
  4. Trypan blue exclusion staining: Trypan blue is a vital stain that selectively stains dead cells. After cell passage, mix the cell suspension with an equal volume of trypan blue solution and incubate for a few minutes. Then, perform a cell count using a hemocytometer or an automated cell counter. The trypan blue dye will stain the apoptotic cells, making them distinguishable from viable cells. Exclude the trypan blue-stained cells from your cell count and subsequent culturing.
  5. Apoptosis inhibitors: If you consistently observe a high level of apoptotic cells even after employing the above methods, you may consider using apoptosis inhibitors in your culture medium. These inhibitors can help reduce the apoptotic cell population. Commonly used apoptosis inhibitors include Z-VAD-FMK and Q-VD-OPh, among others. Follow the recommended concentration and treatment duration provided by the supplier.
All the best
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After analyzing PI data of LN229 cells (glioma cell line), I observed that even the control (untreated) population had the following cell cycle proportion:
G0/G1 : 79%
S : 8%
G2/M: 13%
Is this a valid data? As far as cells are concerned, I don't find any morphological or divisional variation.
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I have not used the same cell line but 80% seems a bit high. I usually see ~50% in my cell lines.
Possibly check the passage number of your cells and make sure they're not scenescent.
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I am trying to do a shRNA gene silencing for an esophageal cell line.
Does anyone have any specific protocol to suggest?
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Hi Anna, I think you can give it a try. shRNA molecules are processed within the cell to form siRNA which in turn knocks down gene expression. So, it might be that you can transfect cells with the protocol I have provided to you and use shRNA with it.
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Hello, I am having trouble producing a protein using the Expi293 cell line.
To be clear, I have successfully produced this protein using the mother cell line but after freezing and thawing the daughter cell lines, I keep failing.
When the product first came, I thawed the cells and subcultured them until P3, which is when I froze the cells for later usage. I transfected the mother cell line with the Expifectamin transfection kit and successfully produced the proteins with good yield. The cells were subcultured until P20, which is when I discarded the cells and thawed the cyropreserved cells.
The cells divide in a healthy condition with normal morphology, but they simply fail to produce the desired proteins following transfection. I have tried using a completely freshly new transfection kit and culture media but this didn't help.
The conclusion I have reached is perhaps (by incredibly bad luck) the Expi293 cell line lost its protein producing ability during freezing procedure. Has anyone experienced such problems regarding protein production (even better if you have used the Expi293 cell line)? I would love to hear opinions and tips to make this work.
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The mother cell line worked fine for 20 passages. I'll try stocking the cells with lower percentage of DMSO once the new cells arrive.
Best regards,
Youngjae
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Hello,
I am trying to do polysome profiling experiment with MEF cell line, but it doesn’t work ( attached the profile I got).
I did the same protocol with different cell lines ( HEKs & U87) and it works very well. I thought maybe the transcriptome in MEFs is low and I should increase my starting material ( maybe I should use two 15cm plates instead of one plate).
What do you think the problem is?and how I can improve my experiment?
Thank you
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sure. CHX prevents the detachment of the ribosomes from the mRNAs , this way we can get a separation between polysome and monosomes when we centrifuge the samples. DTT is used to protect the RNA from degradatio, I think by reducing RNAses. sorry for the late reply
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Hi,
I am carrying out the MTT assay using BJ-5ta fibroblasts cell line to evaluate the cytotoxicity of the nanocomposite hydrogels. I want guidance about deciding the controls in the experiment.
blank: media+MTT solution (to cancel the background noise)
positive control: Cells+media+MTT solution
control hydrogel (containing no nanoparticles)
hydrogels (containing different concentrations of the nanoparticles)
negative control : here I am confused and need guidance, whether it should be DMSO+cells+MTT solution
I will be grateful for your help!
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Blank: NO CELLS + media + MTT solution + DMSO (solubilizing agent)
Positive control for cytotoxicity: Cells treated with nanoparticles already known to have a cytotoxic effect (other than the one you are testing) + media + MTT solution + DMSO (solubilizing agent)
Control hydrogel (containing no nanoparticles) + media + MTT solution + DMSO (solubilizing agent)
Hydrogels (containing different concentrations of the nanoparticles) + media + MTT solution + DMSO (solubilizing agent)
Negative control: Untreated cells + media + MTT solution + DMSO (solubilizing agent)
Controls will help to indicate whether the MTT assay is working. The positive control is an indication for cytotoxicity of the nanoparticles having a known outcome (which is known before hand) while the negative control is an indication for cell proliferation. For the positive control one will obtain less than 100% viability depending on the toxic effect of the known nanoparticle while the negative control should give 100% viability if the assay has worked correctly.
Best.
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Does anyone have a mouse PD-L1 knockout cell line they can share?
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Hi William L Redmond , not sure if you are still looking for mouse PD-L1 knockout tumor cells - but I came across three listings here by Applied Biological Materials:
I hope this helps!
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Dear Colleagues,
We routinely use MTT assay to test the cytotoxicity of compounds. Recently, however, our background values of some cell lines (e.g., MCF7, MDA-MB-231) are shallow, while other cell lines give normal background levels. We excluded infection of the cultures. Have you experienced similar results? How can we fix this?
Tnaks in advance
Istvan Zupko
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Dear Guarav,
thanks for your suggestion, we have tested for mycoplasma but additional test will be performed. Hopefully we will clarify the reason of our problem soon.
Thanks again
kind regards
Istvan
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Hi!
My project includes 2 cell lines (developed from a stock culture) then each cell line was subcultured into 18 flasks. These 18 flasks are then separated into 3 temperatures and incubated for 6 time points. At each time point, I would analyze 2 flasks (one from each cell line), and this flask is discarded after.
Right now, we have the data analyzed with a mixed ANOVA model (time vs temperature as within factors) and tukey (to determine any differences between temperature, time point, and cell line). I was wondering if this is correct? Or should we do it differently because each time point uses a different flask compared to the next (meaning different cells from the stock culture).
thanks!
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Based on the description of your project, it appears that you have a nested experimental design, with a hierarchical structure of observations. Specifically, you have two cell lines, each of which is subcultured into 18 flasks. These flasks are then subjected to different temperatures and time points, with analysis conducted on two flasks at each time point. Each flask represents a unique unit of observation within its respective cell line.
Considering the nested structure of your data, a mixed ANOVA model can be appropriate to analyze the effects of temperature and time, while accounting for the nesting of flasks within cell lines. This model allows you to examine the main effects of temperature and time and their interaction. The mixed ANOVA model would consider temperature and time as within-subject factors while treating cell line as a between-subject factor.
However, it is crucial to acknowledge that using different flasks for each time point introduces potential variability due to the distinct culture conditions and individual variations among the flasks. This variability may affect the results' interpretation and could confound the effects of temperature and time.
To address this concern, you may consider using a random effects model that explicitly accounts for the nested structure of the data. This type of model would allow for the inclusion of random effects to capture the variability associated with the specific flask and cell line. You can better account for the variability between different flasks within the same cell line by incorporating random effects.
Furthermore, it's important to consider the potential impact of using different flasks at each time point on the interpretation of your results. The fact that each flask represents a unique sample from the stock culture introduces the possibility of variability due to factors such as clonal variation and experimental conditions at the time of subculturing. It's essential to carefully consider the implications of this design aspect and discuss them with domain experts or statisticians to ensure appropriate analysis and interpretation of the results.
In summary, while a mixed ANOVA model can be a suitable approach for analyzing the effects of temperature and time, considering the nested structure of your data, you may also want to explore random effects models that explicitly account for the variability associated with the nested design. Additionally, carefully consider the potential implications of using different flasks at each time point on the interpretation of your results. Consulting with experts in experimental design and statistics would be beneficial in guiding you toward the most appropriate analysis for your specific study design.
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Hi,
I am trying to grow JIMT-1 (breast cancer) cell line. However, the cells fail to attach to the surface of the T25 flask. I have contacted the seller but they only provided me with a generic troubleshooting procedure, which I have been following. I want to try and recover this cell line. So, other than growth supplements, is there any suggestion to work on the same?
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Hi Malcom,
This is such a good input, I will check up on it. Thank you for your response.
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Hi, I want to evaluate oxidative stress in a neuroblastoma cell line, I know about SOD1, but I think it's not enough, so I was investigating and I found 4-hydroxynonenal, I have this in my lab 4-HNE B5605, but I don't find the concentration to use. Also I don't think it is the best marker for inmunofluorescence, It is more used in western blot . Do you know other types of marker that I can use for oxidative stress in a cell culture? I will appreciate your help.
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You could try using H2DCFDA. It is mainly used in fluorometry and flow cytometry but you can also find publications using it in immunofluorescence. I could provide you with a protocol but you would have to wait some weeks cause I am currently optimizing it. Use live cells, do a quick test using H2O2 as a positive control and I hope it works out for you.
I wish you best of luck,
George
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How can we optimize the activity of a cell type-specific promoter driving a GFP reporter? We observed a remarkably weak expression of the reporter gene in the cell line. In contrast, native animal cells exhibit significantly higher promoter activity.
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r promoter sequence This would indicate that you are missing some upstream or downstream enhancers in your promoter sequence. How many kbp did you clone? Sometimes including the first/second intron can help.
nr promoter sequence This would indicate that you are missing some upstream or downstream enhancers in your promoter sequence. How many kbp did you clone? Sometimes including the first/second intron can help.
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I am working with HeLa and SiHa cell lines. I would like to have one other normal cell line alongside these cancer cell lines, to identify the effect of the drug in other normal cell lines. Is it mandatory for me to take any normal cell line of cervical origin or can I use any other cell lines like fibroblast?
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Thank you
Mansoureh Nazari v. and Malcolm Nobre for your response. It will be highly useful.
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I want to perform MTT assay for BJ-5ta and HaCat cell lines. I want to know before performing the actual experiment how many passages should be done of the cell lines?
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The cell lines used for any cell-based assay should be of the early passage preferably (between P15- P25). They should be healthy, and you should use the cells when they are in the exponential phase of growth (i.e., when the cells are actively proliferating). If the cells are already in culture and they look healthy, you may go ahead and use them for the MTT assay. But if the required cells are stored in liquid nitrogen or frozen in -80 degree C, you need to thaw these cells and subculture them for a few passages (preferably 2-3 passages) before you use them for the MTT assay. However, some cells may take beyond passage 2 to revive completely after thawing.
So, cells used for MTT, or any other cell-based assay should be in good healthy condition (morphologically and actively proliferating) to enable one to obtain reliable results.
Best.
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We are interested in transfecting a CHO cell line to produce a recombinant protein.
We are planning to use the limiting dilution method in 96-well plates to select single-cell clones to be screened for expression and we are looking for a detailed protocol for this cell line. Specifically, we would also be interest to know the cloning efficiency with this cell line (i.e. the expected ratio between wells plated and clones obtained).
 
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Hi!
Did anyone use any kind of FBS alternative to better the chances of survival of the ExpiCHO cells?
Please let me know.
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I am curious to know if there is a cell line available that can produce both WNT 3A and Rspondin conditioned medium simultaneously?
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A few cell lines can produce both WNT3A and R-spondin conditioned medium simultaneously. These include:
  • L-WRN cell line (ATCC CRL-3276): This cell line is a mouse L cell line that has been engineered to secrete WNT3A, R-spondin-3, and Noggin. (Already mentioned by Dr. Malcolm)
  • 3dGRO™ L-WRN Conditioned Media Supplement (Sigma-Aldrich): This product is a formulation based on DMEM/F-12 PLUS medium containing the 3 growth factors WNT3a (W), R-spondin-3 (R), and Noggin (N).
  • 293T-HA-Rspol-Fc cell line (Trevigen): This cell line is a human 293T cell line that has been engineered to secrete R-spondin-1.
These cell lines can generate a conditioned medium rich in WNT3A and R-spondin, which is essential for the growth and maintenance of intestinal organoids.
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I'm working with Platinum-E (Plat-E) cells and generating viral particles that carry an insert of interest with a GFP reporter that will be used to infect mouse T cells. I understand that when working with lentiviruses, you would typically infect 293T cells (or a similar cell line) and measure how many cells are positive for GFP to determine your functional viral titer. You would then move on to determine the MOI of your cell type of interest. However, retroviruses produced by Plat-E cells are ecotropic and only infect mouse/rat cells. Thus, I would have to infect a mouse cell line to determine my functional viral titer. Do researchers working with mouse retroviruses typically do this? (Determine functional viral titer by infecting mouse cells). If so, what cell line/type is typically used for determining viral titers. Or is it standard to just jump straight to infecting your cell type of interest?
Thanks in advance for any advice and information!
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You can probably use absorption spectroscopy to get an estimate if you have a relatively pure solution of your viral particles.
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I have problem about MTT assay in U87 cell line. After add MTT solution in U87 cell line, the cell were floated. Who used to find the same problem. Why is cause of this action? Please answer and suggest me for solving of the problem. Thank you.
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I too faced a similar problem but with the cells in the side wells of a 96-well plate, which detached with complete layer after some time while the cells in the middle wells stayed attached.
Later I found a solution to this problem. It was because of the 'Edge Effect'. Temperature difference across the plate and evaporation effects in the side wells during incubation was the cause of such type of cell behavior. In the side wells, because of evaporation, salts from the culture medium accumulate in the wells affecting cell attachment and metabolism.
If you are experiencing cell detachment for the entire 96-well plate, then I would suggest you work gently with these cells at all times as vigorous or harsh handling of cells can result in cell detachment and damage or even cell death. Never pipette medium or wash buffer directly onto cells, always add it gently to the side of the well to avoid harming the cells.
Best.
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I did today tissue culture for mcf7 cell line( breast cancer) and i check my work under microscope i saw this below is this cancer cell or just cells debris?
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Hi Shahad,
How many days have passed since you passaged these cells? While there are few healthy ones showing up in a different phase contrast, many of your cells are dying or do not look healthy unfortunately. MCF-7 cells do tend to grow slowly at times. Harsh passaging conditions should be avoided. You may try using a milder cell dissociation agent like Accutase instead of Trypsin during passaging.
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Hi I am kind of looking to see if a comparative expression level analysis of the different Glycosylation enzymes of different CHO cell lines (DG44, DXB-11 and K1)is available in any publication. I am new to this field and a little help will be greatly appreciated. Thanks in advance.
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Bandla Ramesh I could not find the paper. Do you have the DOI? Kindly share it.
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Hi,
I am working on my PhD project and recently we plan to have our experiments using immortalized nasoepithelial cell line. First we tried ABM T9245 with the Prigrow serum the company suggested, with pre-coated vessels, however the cells didn't attach at all. For some other issue we asked for a compensating vial ABM T0440, along with the suggested serum and precoated culturing vessels. This is the second day after thawing, and the cells don't attach at all either.... Does anyone who worked with similar cell types have any idea what's wrong? or offer any suggestions?
I thawed the cells using 1 min 37 degree water bath, then resuspended in 5 mL Prigrow X, followed by 200g x 3 min centrifuge and finally resuspension and seeding as suggested density.
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Hello, We also purchased cell from abm company. Is there any alternative culture media you find that can replace their suggested media?
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I seeded 8000 cells per well in 1 96 well plate. The number I think is very high for T84. So, I need the doubling time of T84.
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I was lacking in the Cellosaurus entry the DT for T84, however I uncovered a paper:
Which has DT for T84 of 33.9 hours in the supplemental table 1. This informaation and the other 52 cell line doubling times reported by this publication will be added to the next release of the Cellosaurus. So your question was very useful, thank you!
Best regards
Amos
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Can I get the paper related to p53 mutation and HS578T cell line.
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You can look up the improtant oncogenic mutations (including p53) of that cell line in its Cellosaurus entry:
In it you will see that the p53 mutation for that cell line has been reported in five different papers.
Best
Amos