[Show abstract][Hide abstract] ABSTRACT: Mannose-binding lectin (MBL), a plasma C-type lectin, plays an important role in innate immunity. However, the interaction, and the consequences of it, between MBL and the immune system remain ill defined. We have investigated the contributing mechanisms and effects of MBL on the proliferation of human monocytes. At lower concentrations (≤4 μg/ml) MBL was shown to partially enhance monocyte proliferation. By contrast, at higher concentrations (8-20 μg/ml) of MBL, cell proliferation was markedly attenuated. MBL-induced growth inhibition was associated with G0/G1 arrest, down-regulation of cyclin D1/D3, cyclin-dependent kinase (Cdk) 2/Cdk4 and up-regulation of the Cdk inhibitory protein Cip1/p21. Additionally, MBL induced apoptosis, and did so through caspase-3 activation and poly ADP-ribose polymerase (PARP) cleavage. Moreover, transforming growth factor (TGF)-β1 levels increased in the supernatants of MBL-stimulated monocyte cultures. We also found that MBL-dependent inhibition of monocyte proliferation could be reversed by the TGF-β receptor antagonist SB-431542, or by anti-TGF-β1 antibody, or by the mitogen-activated protein kinase (MAPK) inhibitors specific for p38 (SB203580), but not ERK (U0126) or JNK (SP600125). Thus, at high concentrations, MBL can affect the immune system by inhibiting monocyte proliferation, which suggests that MBL may exhibit anti-inflammatory effects.
PLoS ONE 09/2013; 8(9):e72505. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the effects of mannan-binding lectin (MBL) on the functions of human polymorphonuclear cells (PMNs).
ELISA and Dot blot were performed to examine the binding between MBL and the microorganisms. Flow cytometry and fluorescence microscopy were employed to analyze the phagocytosis of FITC-labeled microognisms by the PMNs. Real-time quantitative PCR was used to detect the expression levels of IL-1β, TNF-α and CD11b mRNA in the PMNs, and ELISA used to detect the levels of TNF-α and IL-6 in the supernatants of PMN culture. Nitro-blue tetrazolium reduction assay was used to estimate the levels of superoxide production.
MBL bound to the microorganisms in a dose-dependent manner. MBL had no significant effect on phagocytosis of C. albicans and E.coli by the PMNs in the absence of human serum, but in presence of mixed MBL-deficient human sera, MBL promoted the phagocytosis of C. albicans, which could be blocked by mannan. Mannan treatment increased the expressions of IL-1β, TNF-α, IL-6 and CD11b and enhanced superoxide production in the PMNs.
MBL can promote phagocytosis of microorganisms by PMNs and increase the expressions of proinflamatory cytokines from PMNs in a complement lectin pathway-dependent manner.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 06/2013; 33(6):842-846.
[Show abstract][Hide abstract] ABSTRACT: The treatment of chronic diabetic wounds remains complicated, despite new insight into the cellular and molecular basis of wound healing and cutaneous regeneration. A growing body of clinical trials has shown that platelet release has a notable effectiveness on refractory ulcer healing. However, patients with chronic diabetic ulcers usually have poor general health, and the large-volume blood absence required to produce autologous platelet-rich plasma often causes adverse effects. To overcome the limitation, the homologous platelet gel (PG) from healthy donor was used for the treatment of chronic diabetic lower extremity wound in the study. We show here that homologous derived platelets significantly enhanced EVC304 cell and HaCaT cell proliferation and homologous PG was capable of prompting cell migration. Twenty-one patients with refractory diabetic lower extremity ulcers, who had no response to conventional treatments, were treated in this study. Our data indicated that homologous PG was effective for the enhancement and acceleration of diabetic lower extremity wounds healing. We propose that homologous PG appeared to enhance vascularization and epithelialization, which might induce a quicker healing process and and encourage controlled studies in future.
The International Journal of Lower Extremity Wounds 03/2013; 12(1):22-29. · 1.25 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To prepare the trimeric subunits of recombinant human mannan-binding lectin (MBL) with biological activities.
A prokaryotic expression vector containing human MBL N-terminal deletant (rhMBLδN) gene we previously constructed was transformed into E. coli for efficient expression of rhMBLδN fusion protein. Based on the principle that the collagen polypeptides tend to self-assembly into the tertiary structure of proteins by forming a triple helix due to the characteristic properties of the collagen proteins, rhMBLδN fusion protein was limitedly hydrolyzed with thrombin. The obtained rhMBLδN polypeptide was repeatedly dialyzed in 50 mmol/L PBS (pH7.2) and ddH(2)O, and the final product was analyzed for its bioactivities using a ligand-binding assay and a C4d deposition assay.
rhMBLδN polypeptide with a relative molecular mass of about 20 000 was obtained by limited proteolysis of rhMBLδN fusion protein with thrombin. Repeated dialyses of rhMBLδN polypeptides in 50 mmol/L PBS and ddH(2)O resulted in the isolation of the trimeric subunit trhMBLδN (with a relative molecular mass of about 50 000), which contained a collagen-like helix. The trhMBLδN protein had a higher ligand-binding activity than rhMBLδN polypeptide, and acquired the activity to initiate the lectin pathway of complement activation, but the activities were lower than those of natural MBL.
We have successfully obtained the bioactive trimeric subunit of rhMBL, trhMBLδN, and this structural subunit is also the functional subunit of the MBL molecule.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 11/2012; 32(11):1584-7.
[Show abstract][Hide abstract] ABSTRACT: Human mannan-binding lectin (MBL) plays a pivotal role in innate immunity. Substantial literature supports the belief that three point mutations, CGT52TGT, GGC54GAC and GGA57GAA, in the collagen-like region (CLR) of the human MBL gene, are associated with increased susceptibility to infection, autoimmunity and carcinogenesis. To investigate the mechanisms of MBL deficiency, human wild-type and three variant MBL genes were expressed in COS-7 and Chinese hamster ovary (CHO) cells. Results showed that no apparent differences were found among the levels of gene transcription and protein secretion of four forms of MBL. However, the degree of oligomerization of variant forms of MBL was found to be much lower than that of recombinant human wild-type MBL. The ability of variant MBL proteins to bind mannan was much weaker than that of the wild-type MBL protein, and the MBL variants failed to effectively activate the complement lectin pathway. These data suggested that a lower order oligomer, but not decreased plasma levels of MBL, may be the main result of MBL gene mutations and may be associated with immunodeficiency.
Molecular Medicine Reports 04/2012; 5(4):1121-7. · 1.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mannan-binding lectin (MBL) is a C-type serum lectin, which is believed to play an important role in the innate immunity against a variety of pathogens. MBL can bind to sugar determinants of a wide variety of microorganisms, neutralize them and inhibit infection by complement activation through the lectin pathway and opsonization by collectin receptors. Given that small intestine is a predominant site of extrahepatic expression of MBL, here we addressed the question whether MBL is involved in mucosal innate immunity. The carbohydrate recognition domain (CRD) genes of mouse MBL-C (mMBL-C) were cloned and expressed in Escherichia coli. Recombinant mMBL-C-CRD binds to Shigella flexneri 2a in a calcium-dependent manner and that interaction could be blocked by the anti-mMBL-C-CRD antibody. mMBL-C-CRD protein could inhibit the adhesion of S. flexneri 2a to intestinal mucosa, while administration of anti-mMBL-C-CRD antibody caused an increased level of bacteria adhesion in vitro. Administration of recombinant mMBL-C-CRD protein reduced the secretion of IL-6 and monocyte chemoattractant protein 1 from primary intestinal epithelial cells stimulated with S. flexneri 2a. Furthermore, neutralization of MBL activity by anti-MBL-C-CRD resulted in a significant increase in the number of S. flexneri 2a that colonized the intestines of BALB/c mice and attenuated the severity of inflammation seen in the areas of bacterial invasion. These findings suggest that mMBL-C may protect host intestinal mucosa by directly binding to the bacteria.
International Immunology 09/2009; 21(10):1125-34. · 3.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To obtain the intact encoding gene of human DC-SIGN and express its extracellular region in E.coli.
The intact cDNA encoding human DC-SIGN was amplified from total RNA of placenta of healthy parturient by RT-PCR, and its extracellular region was inserted into prokaryotic expression vector pET-41a. The recombinant plasmid pET-41a-sDC-SIGN was transformed into E.coli BL21(DE3). The expressed product was purified by GST affinity chromatography and identified by SDS-PAGE and Western blot.
The DNA fragment of about 1 300 bp was amplified by RT-PCR, and cloned into pGM-T vector to obtain the recombinant plasmid pGM-DC-SIGN. The DNA fragment encoding the extracellular region of human DC-SIGN was amplified from pGM-DC-SIGN plasmid and the recombinant expression vector pET-41a-sDC-SIGN was constructed. The component of M(r); 66 000 in the purified recombinant product was found to be recognized by anti-DC-SIGN antibody.
The cDNA of human DC-SIGN is cloned and the protein of its extracellular region is obtained successfully, which lay the foundation for further research on functions of DC-SIGN.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 06/2009; 25(5):396-8.
[Show abstract][Hide abstract] ABSTRACT: To express the carbohydrate recognition domain (CRD) of Balb/C mouse mannan binding lectin A (MBL-A) in E.coli.
The target gene fragment was obtained by PCR from the plasmid pmMBL-A harboring mouse MBL-A gene. The PCR product was recombined with the prokaryotic expression vector pET-41a(+) and the resulting recombinant plasmid was identified by PCR, restriction analysis and sequencing before transformation into E.coli BL21(DE3) cell for expression of the target protein. After washing and renaturation, the protein was purified on GST-Tag purification resins and analyzed by SDS-PAGE, Western blotting and enzyme-linked immunosorbent assay (ELISA).
A DNA fragment of about 450 bp was amplified by PCR and the recombinant plasmid pET41a-mMBL-A-CRD was constructed by linking the fragment with pET41a(+) vector. The result of restriction enzyme analysis and sequencing of the selected clones were consistent with those by computer analysis. The recombinant vector was expressed in E.coli BL21(DE3), and the expressed protein existed mainly as inclusion bodies, whose relative molecular mass was about 47,000 by SDS-PAGE analysis. After washing, renaturation and purification, the purity of recombinant protein was about 90%. Western blotting suggested immunoreactivity of the purified protein with anti-GST antibody, and its sugar binding activity was verified by ELISA.
We have successfully obtained mouse MBL-A CRD protein, which provides the base for further functional study of the MBL-A molecule.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 03/2009; 29(2):267-70.
[Show abstract][Hide abstract] ABSTRACT: To express the N-terminal fragment of human mannan-binding lectin (MBL) associated serine proteases-1 (MASP1-N) in E.coli.
The target sequence in pGEM-MASP1 plasmid that contains human MBL-MASP1 cDNA was amplified by PCR, inserted into prokaryotic expression vector pGEX4T-1 and identified by restriction mapping and sequencing. The recombinant expression vector was transformed into E.coli BL21 (DE3) cells. The expressed product was purified by GSTrap Immobilized Metal Affinity Chromatography(IMAC) and identified by SDS-PAGE and Western blot assay, its binding-activity with the collagen-like region of human MBL(MBL-CLR) and with recombinant human MBL was analyzed by an indirect enzyme-linked immunosorbent assayèELISAé.
The DNA fragment of 860 bp, which encode the N-terminal region of human MASP1, was amplified from pGEM-MASP1 plasmid and the recombinant expression vector, pGEX4T-MASP1-N, was constructed, whose restriction maps and sequence were consistent with those expected. The component of M(r) 60 000 in the purified recombinant product was found by SDS-PAGE and could be recognized by anti-GST antibody in Western blot assay. The purified recombinant product could react with human MBL-CLR and human MBL in the indirect ELISA.
The prokaryotic cell strain that expresses efficiently recombinant human MASP1-N(rhMASP1-N) protein and the purified rhMASP1-N protein were successfully obtained, which provides the basis for further research of MASP1 molecule.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 07/2008; 24(6):546-9.
[Show abstract][Hide abstract] ABSTRACT: To obtain highly purified tetanus toxin fragment C (TTC) with good immunogenicity.
The gene fragment encoding TTC was amplified from Clostridium tetani plasmid DNA by PCR, inserted into the vector pET43.1a (+) and expressed in E. coli BL21(DE3)plysS. After purification using Ni2+-chelate affinity chromatography, the expressed fusion protein was digested by thrombin and the resultant TTC protein was purified with Ni2+-chelate affinity chromatography followed by identification with SDS-PAGE and Western blotting. The purifed TTC protein was then used to immunize mice to test its immunogenecity.
The 1373-bp gene fragment encoding TTC was obtained, and the constructed recombinant expression vector pET43.1a (+)-TTC was successfully expressed in E. coli BL21(DE3)plysS. SDS-PAGE identified a recombinant fusion protein with relative molecular mass (Mr) of 117 000, which accounted for 22% of the total bacterial protein. The TTC protein with Mr of 50 000 was obtained after purification of the thrombin digestion products of the fusion protein, with a purity reaching 95.5%. Both the fusion protein and TTC protein could be recognized by anti-tetanus toxin antibody as shown by Western blotting. The titer of the anti-serum from mice immunized with the TTC protein was 1:25 600, and the anti-serum could specifically bind to tetanus toxin.
Highly purified and immunogenetic TTC protein has been successfully obtained, which provides a good model antigen for studying antigen presentation and immune responses in vivo.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 06/2008; 28(5):731-5.
[Show abstract][Hide abstract] ABSTRACT: To prepare a single-epitope polyclonal antibody against mouse long peptidoglycan recognition protein (mPGRP-L).
B cell dominant epitopes of mPGRP-L predicted by bioinformatics were synthesized, and the immunogen was prepared by conjugation of the synthetic peptide and the carrier protein key-hole limpet hemocyanin (KLH) by MBS method. The single-epitope polyclonal antibody was obtained by immunizing rabbits with the KLH-peptide conjugate, purified by SPG affinity columns or antigenic peptide affinity columns, and identified by ELISA and Western blotting.
A dominant epitope in N-terminal region of mPGRP-L, with amino acid sequence of NH(2)-(C)DPHSLSPELQALISEVAQHD-COOH, was chosen and synthesized. The titer of anti-serum of the rabbits immunized with the KLH-peptide conjugate was 1:256,000. The polyclonal antibody purified with SPG affinity columns and antigenic peptide affinity columns were named as mPGRP-Ln1 and mPGRP-Ln2, respectively. Western blotting demonstrated that the antibody mPGRP-Ln1 could recognize the recombined N-terminal fragment of mPGRP-Ln with a clear band at relative molecular mass of about 29,000, suggesting the successful preparation of the single-epitope polyclonal antibody against the N-terminal region of mPGRP-L.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 07/2007; 27(6):859-62.
[Show abstract][Hide abstract] ABSTRACT: To construct pET32a/His MBL-CLR recombinant prokaryotic expression plasmid and to express mannan-binding lectin-CLR (MBL-CLR) protein in E.coli
The human MBL-CLR gene was amplified by PCR from pGEM-MBL plasmid, and was inserted into prokaryotic expression vector pET32a. After identified by restriction mapping and sequencing, the recombinant plasmid pET32a/His MBL-CLR was transformed into E.coli BL21 (DE3) cells. The expressed product was purified by Immobilized Metal Affinity Chromatography (IMAC) and identified by SDS-PAGE, Western blot and indirect enzyme-linked immunosorbent assay (ELISA) using the antibody from BALB/c mice immunized with the recombinant human MBL protein.
The cDNA fragment of 180 bp was amplified from pGEM-MBL plasmid and the recombinant expression vector pET32/His MBL-CLR was constructed. The recombinant plasmid was consistent with those expected by restriction maps and sequence. Three components of relative molecular mass 30,000, 60,000 and 120,000 in the purified recombinant product were detected by SDS-PAGE and all the components could be recognized by anti-6His antibody in Western blot assay. The three components were correspondingly with the band of the monomer and oligomer of the fusion protein. The purified recombinant product could react with the antibody against the recombinant human MBL protein in the indirect ELISA.
The prokaryotic expression strains that efficiently express recombinant human MBL-CLR and the recombinant human MBL-CLR-Trx fusion protein were obtained successfully, which will help the further structure-function research of MBL molecule.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 02/2007; 23(1):25-7, 31.
[Show abstract][Hide abstract] ABSTRACT: To investigate the frequencies of three point mutations, CGT52TGT, GGC54GAC and GGA57GAA, in exon 1 of mannan-binding lectin (MBL) structural gene in Chinese Uyghur population.
Blood samples were collected from a Uyghur population in Xinjiang Uyghur Autonomous Region, and the genomic DNA was extracted from the leucocytes and the target gene fragment amplified by PCR. The three point mutations in exon 1 of MBL gene were detected by fluorogenic probe hybridization technique with visual monitoring.
In 95 Uyghur individuals, 2 were identified as homozygous for codon 54 mutations, 28 were heterozygous for codon 54 mutation, and no CGT52TGT and GGA57GAA point mutations were found.
The frequencies of CGT52TGT, GGC54GAC and GGA57GAA mutant alleles in exon 1 of MBL structural gene are 0, 0.168 and 0 respectively in the Chinese Uyghur population.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 01/2007; 26(12):1764-7.
[Show abstract][Hide abstract] ABSTRACT: To clone the gene coding for the peptidoglycan recognition protein (PGRP) domain (PGRPd) of mouse long PGRP (mPGRP-L) and express the protein in E. coli.
The cDNA fragment encoding PGRPd of mPGRP-L was obtained by RT-PCR from the total RNA of Balb/C mouse liver cells and cloned into pUCm-T vector. The recombinant plasmid were identified by PCR, restriction endonucleases and sequence analysis. The PGRPd gene fragment was amplified by PCR from the recombinant plasmid, inserted into pQE-30 vector and transformed into E. coli strain M15, and the expressed PGRPd protein was purified.
A cDNA fragment of about 500 bp was amplified by RT-PCR and the recombinant plasmid, pmPGRPd, was constructed by linking the fragment to pUCm-T vector. The results of restriction mapping of the recombinant vector were consistent with those of computer analyses. Sequence analysis showed that the cloned gene fragment (518 bp) had identical sequence with the gene encoding PGRPd of mPGRP-L gene in GenBank. The recombinant expression vector pQE-PGRPd was constructed and expressed in E. coli M15. SDS-PAGE showed that the expressed product existed mainly in the lysate supernatant as a soluble protein with relative molecular mass of 29 kD.
The PGRPd cDNA of mPGRP-L has been successfully cloned and expressed in E. coli, which provides the basis for further study of PGRP molecule.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 05/2006; 26(4):472-5.
[Show abstract][Hide abstract] ABSTRACT: To construct the standard recombinant plasmids for 7 common haplotypes of mannan-binding lectin (MBL) gene.
The DNA samples with known haplotypes and genotypes of MBL gene were used as the templates for amplifying the fragments of MBL gene haplotypes including the promoter region and exon 1 with sequence-specific primer-polymerase chain reaction (SSP-PCR) method. The amplified fragments were cloned into T vector and the bases located at codon 52 and codon 57 of exon 1 in MBL gene were mutated respectively by site-directed mutagenesis. All the 7 recombinant plasmids were identified by PCR and direct sequence analysis.
From the DNA samples with known haplotypes and genotypes of MBL gene, the standard plasmids of haplotypes HYPA, LXPA, LYQA, LYPA and LYPB of MBL gene were constructed by SSP-PCR and molecular cloning technique. From the recombinant plasmids of HYPA and LYQA, the standard plasmids of haplotypes HYPD and LYQC of MBL gene were constructed by site-directed mutagenesis, respectively.
The constructed standard plasmids of haplotypes HYPA, LXPA, LYQA, LYPA, LYPB, HYPD and LYQC of MBL gene provide standard controls for detecting the SNPs, haplotypes and genotypes of MBL gene with such genotyping methods us SSP-PCR and real-time PCR.
Di 1 jun yi da xue xue bao = Academic journal of the first medical college of PLA 12/2005; 25(11):1379-83.
[Show abstract][Hide abstract] ABSTRACT: To explore the role of complement C3 in delayed-type hypersensitivity (DTH).
After inducing DTH reaction in the footpads of C3 knockout C3(-/-) and wild-type (C3(+/+) ) mice with ovalbumin (OVA), the thickness of the footpad was measured and HE and immunohistochemical staining preformed to identify the number and types of the infiltrating mononuclear cells in the footpad tissues. T lymphocytes were separated from the spleens of the mice and incubated in 96-well plates with serial dilutions of OVA or mitogens in the presence of mitomycin C-treated macrophages, and the proliferation of the T cells was assessed by (3)H-TdR incorporation assay.
The footpad thickness of DTH-C3(-/-) mice was significantly smaller than that of DTH-C3(+/+) mice. The number of the infiltrating mononuclear cells in the footpad tissue of C3(-/-) mice was obviously decreased in comparison with that of C3(+/+) mice, and the cells were characterized mainly as CD4(+) T lymphocytes. No significant difference in the proliferation of mitogen-stimulated splenic T cells was noted between C3(-/-) and C3(+/+) mice, but after stimulation with the specific antigen OVA, significant reduction in the proliferation of splenic T cells from C3(-/-) mice was observed as compared with the T cell proliferation in C3(+/+) mice.
C3 defect results in impaired DTH responses in mice, which indicates the important role of C3 in DTH reaction.
Di 1 jun yi da xue xue bao = Academic journal of the first medical college of PLA 12/2005; 25(11):1413-7.
[Show abstract][Hide abstract] ABSTRACT: To explore preliminarily the mechanisms of immunodeficiency resulted from the CGT52TGT point mutation of mannan-binding lectin(MBL) gene.
The MBL gene containing CGT52TGT point mutation was amplified from the plasmid pMBLm52 by PCR, and then inserted into the eukaryotic expression vector pcDNA4/HisMax C. After confirmed by DNA sequencing, the recombinant expression vector was transfected into Chinese-hamster ovary(CHO) cells by electroporation. Zeocin of 800 mg/L had been used for 30 days to select electroporated CHO cells, and then 200 mg/L for another 30 days to obtain stable transfectant. The expression of mRNA was analyzed by RT-PCR, the recombinant protein was purified from the culture supernatant by Ni-NTA agarose chromatography and analyzed by SDS-PAGE under nonreducing condition and Western blot.
The cDNA fragment amplified from pMBLm52 plasmid by PCR was about 750 bp and the recombinant plasmid pcDNA4/HisMax C-MBLm52 was constructed and transfected into CHO cells. The expression product purified from the culture supernatant appeared mainly at the site of M(r) 60,000, indicating a much lower oligomerization level than that of the recombinant human wild MBL and human plasma-derived MBL.
The CGT52TGT point mutation of MBL gene does not affect the secretion of its product, but a Cys introduced by the mutation could form another disulfide bond which may disrupt the structure of MBL molecule as well as its function.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 08/2005; 21(4):399-402.
[Show abstract][Hide abstract] ABSTRACT: To investigate the expression of endogenetic matrix metalloproteinases-9 (MMP-9) and transforming growth factor-beta(TGF-beta) and their role in the wound healing of blast injury.
Rat models of blast injury under a humid and hot environment were established and the effusion from the wound surface was collected at 4, 24, 48 h and 5, 7, 14, 21 and 28 days after injury, respectively. The contents of MMP-9 and TGF-beta in the effusion of the wound were measured by zymography and enzyme-linked immunosorbent assay (ELISA), respectively.
During the wound healing of blast injury, MMP-9 and TGF-beta exhibited changes that followed a regular pattern, both reaching the peak value at 48 h after the injury. TGF-beta content reached the another peak on day 7. TGF-beta value and MMP-9 contents decreased in the second week after injury and their reduction was no longer parallel. Administration of tissue inhibitor of metalloproteinase (TIMP) in the early phase of injury showed no obvious effect, but during the 2 weeks after the injury, its administration caused decrease in MMP-9 content and increase in TGF-beta content in the effusion.
In the early phase of wound healing, the elevation of MMP-9 and TGF-beta accelerated cell migration to promote the clearance of the inflammatory necrosis tissues, which might be one of the wound healing mechanisms. But overexpression of MMP-9 in the wound may hinder wound healing, and appropriate use of TIMP can accelerate the delayed wound healing.
Di 1 jun yi da xue xue bao = Academic journal of the first medical college of PLA 08/2005; 25(7):844-6.
[Show abstract][Hide abstract] ABSTRACT: To explore the effect of mannan-binding lectin (MBL) on the differentiation and maturation of human peripheral blood monocyte-derived dendritic cells (MoDCs).
After MoDCs was stimulated with human natural MBL, MoDC's morphology was observed under inverted microscope and the expressions of CD1a, CD83, CD40, CD80, CD86 and HLA-DR on MoDCs were analyzed by FACS. The ability of MoDCs to stimulate the proliferation of allogenic T cells was detected by (3)H-TdR incorporation. The ability of MoDCs to up-take antigens was evaluated by zymosan granule phagocytosis test. The levels of IL-12 and TNF-alpha in the culture supernatant of MoDCs were determined by ELISA.
The expressions of CD1a, CD83, CD40, CD80, CD86 and HLA-DR on the MoDCs were up-regulated by MBL. The ability of MoDCs to up-take zymosan granules decreased and the proliferation of native T cells induced by MoDCs was enhanced. MBL stimulated the production of IL-12 by MoDCs, but had no such effect on TNF-alpha secretion.
MBL can induce differentiation and maturation of DCs in vitro, suggesting that MBL possibly participate in the adaptive immune response through modulation of functions of DCs.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 04/2005; 21(2):159-62.
[Show abstract][Hide abstract] ABSTRACT: To separate mannan-binding lectin (MBL) and MBL-associated serine proteases (MASPs) from human plasma.
A two-step affinity chromatography on underivatized sepharose 4B was employed for purification of MBL-MASP complex, followed by gel filtration on a Sephacryl S-300 column for separation of MBL and MASPs from the complex. The purification procedures were performed at 4 degrees Celsius with the addition of two proteolytic inhibitors, phenyl methylsulfonyl fluoride and 1,10-phenanthroline during affinity chromatography but not in the gel filtration buffer.
Preparations of highly purified MBL and proenzyme MASPs were obtained. The purified MBL was shown by SDS-PAGE and Western blotting to be a functional multimer composed of 28,000 and 32,000 peptide chains, with high bioactivity as demonstrated by ligand-binding assay and yeast agglutination experiment.
A simple and convenient procedure is established successfully for the purification of MBL and the proenzyme MASPs.
Di 1 jun yi da xue xue bao = Academic journal of the first medical college of PLA 01/2005; 24(12):1373-7.