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ABSTRACT: Our goal is to compare the immunogenicity and the extent of immunologic reactivity between bispecific and mono anti-idiotype vaccines. We previously obtained two human anti-Id antibody fragments fuse5-G22, fuse5-I50 by phage display technology which were mimics of the antigens from nasopharyngeal carcinoma cell line (HNE2). In this study, we developed and characterized a bispecific anti-Id antibody vaccine G22-I50 and its parent monovalent antibody vaccines G22 and I50. The efficacy of G22-I50, G22, and I50 as tumor vaccines was evaluated in Balb/c mice with three injections of these vaccines adjuvanted with Freund's adjuvant. Mice immunized with G22-I50 exhibited comparable levels of antibody titers and stronger binding inhibition capabilities. Spleen cells from G22-I50-immunized mice gave a significant proliferative response and higher expression level of IFN-gamma and IL-2.These results suggested that bispecific anti-Id antibody vaccine was able to induce more powerful humoral and cell-mediated immune responses, which might make it to be a potential vaccine candidate for the therapy of nasopharyngeal carcinoma.
International immunopharmacology 04/2010; 10(6):707-12. · 2.21 Impact Factor
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ABSTRACT: To investigate the role of platelet-derived growth factor receptor-like gene (PDGFRL) in the anti-cancer therapy for colorectal cancers (CRC).
PDGFRL mRNA and protein levels were measured by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry in CRC and colorectal normal tissues. PDGFRL prokaryotic expression vector was carried out in Escherichia coli (E. coli), and purified by immobilized metal affinity chromatography. The effect of PDGFRL protein on CRC HCT-116 cells was detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT), clone counting, cell cycle, and wound healing assay.
Both RT-PCR and immunohistochemistry showed that the expression of PDGFRL in colorectal normal tissues was higher than in cancer tissues. Recombinant pET22b-PDGFRL prokaryotic expression vector was successfully expressed in E. coli, and the target protein was expressed in the form of inclusion bodies. After purification and refolding, recombinant human PDGFRL (rhPDGFRL) could efficiently inhibit the proliferation and invasion of CRC HCT-116 cells detected by MTT, clone counting and wound healing assay. Moreover, rhPDGFRL arrested HCT-116 cell cycling at the G0/G1 phase.
PDGFRL is a potential gene for application in the anti-cancer therapy for CRC.
World Journal of Gastroenterology 03/2010; 16(12):1465-72. · 2.47 Impact Factor
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ABSTRACT: To investigate the effect of nitroglycerin (NTG) on cell proliferation and osteoblastic differentiation of human bone marrow-derived mesenchymal stem cells (HBMSC) and its mechanisms.
Primary HBMSC were cultured in osteogenic differentiation medium consisting of phenol red-free alpha-minimum essential media plus 10% fetal bovine serum (dextran-coated charcoal stripped) supplemented with 10 nmol/L dexamethasone, 50 mg/L ascorbic acid, and 10 mmol/L beta-glycerophosphate for inducing osteoblastic differentiation. The cells were treated with NTG (0.1-10 micromol/L) alone or concurrent incubation with different nitric oxide synthase (NOS) inhibitors. Nitric oxide (NO) production was measured by using a commercial NO kit. Cell proliferation was measured by 5-bromodeoxyuridine (BrdU) incorporation. The osteoblastic differentiation of HBMSC culture was evaluated by measuring cellular alkaline phosphatase (ALP) activity and calcium deposition, as well as osteoblastic markers by real-time RT-PCR.
The treatment of HBMSC with NTG (0.1-10 micromol/L) led to a dose-dependent increase of NO production in the conditional medium. The release of NO by NTG resulted in increased cell proliferation and osteoblastic differentiation of HBMSC, as evidenced by the increment of the BrdU incorporation, the induction of ALP activity in the early stage, and the calcium deposition in the latter stage. The increment of NO production was also correlated with the upregulation of osteoblastic markers in HBMSC cultures. However, the stimulatory effect of NTG (10 micromol/L) could not be abolished by either N(G ) -nitro-L-arginine methyl ester, an antagonist of endothelial NOS, or 1400W, a selective blocker of inducible NOS activity.
NTG stimulates cell proliferation and osteoblastic differentiation of HBMSC through a direct release of NO, which is independent on intracellular NOS activity.
Acta Pharmacologica Sinica 06/2008; 29(5):580-6. · 1.95 Impact Factor
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ABSTRACT: In the current study, we investigated the effects of genistein on adipogenic differentiation of mouse bone marrow-derived mesenchymal stem cell (BMSC) cultures and its potential signaling pathway. The terminal adipogenic differentiation was assessed by western-blotting analysis of adipogenic-specific proteins such as PPARgamma, C/EBPalpha, and aP2 and the formation of adipocytes. Treatment of mouse BMSC cultures with adipogenic cocktail resulted in sustained activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), which are members of the mitogen-activated protein kinase (MAPK) family, at the early phase of adipogenesis (from days 3 to 9). Inhibition of ERK1/2 activation by PD98059, a specific MEK inhibitor, reversed the induced adipogenic differentiation. Genistein dose-dependently decreased the phosphorylation of ERK1/2 in mouse BMSC cultures. Genistein incubation for the entire culture period, as well as that applied during the early phase of the culture period, significantly inhibited the adipogenic differentiation of mouse BMSC cultures. While genistein was incubated at the late stage (after day 9), no inhibitory effect on adipogenic differentiation was observed. BMSC cultures treated with genistein in the presence of fibroblast growth factor-2 (FGF-2), an activator of the ERK1/2 signaling pathway, expressed normal levels of ERK1/2 activity, and, in so doing, are capable of undergoing adipogenesis. Our results suggest that activation of the ERK1/2 signaling pathway during the early phase of adipogenesis (from days 3 to 9) is essential to adipogenic differentiation of BMSC cultures, and that genistein inhibits the adipogenic differentiation through a potential downregulation of ERK1/2 activity at this early phase of adipogenesis.
Journal of Cellular Biochemistry 05/2008; 104(5):1853-64. · 2.87 Impact Factor
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ABSTRACT: 1. Clopidogrel is one of the most important antithrombotic drugs but has different efficacies in different populations. The aim of the present study was to evaluate the contribution of CYP2C19 genetic polymorphisms to the inhibition of ADP-induced platelet aggregation by clopidogrel in healthy Chinese volunteers. 2. Eighteen healthy male volunteers (six CYP2C19*1/CYP2C19*1, six CYP2C19*1/CYP2C19*2and*3 and six CYP2C19*2/CYP2C19*2and*3) were enrolled in the study. Each subject took 300 mg clopidogrel on the first day and then 75 mg once daily for 2 consecutive days. Blood samples were taken to measure ADP-induced platelet aggregation at baseline and 4, 24 and 72 h after administration of the first dose of clopidogrel. 3. There were significant decrease in 2 and 5 micromol/L ADP-induced platelet aggregation at 4, 24 and 72 h after clopidogrel among the three CYP2C19 genotypes compared with baseline (P < 0.001). The change in 5 micromol/L ADP-induced platelet aggregation in subjects with the CYP2C19*1/CYP2C19*1 genotype was greater than that in subjects with the CYP2C19*2/CYP2C19*2and*3 genotype at 4 h (49.0 +/- 15.5 vs 29.7 +/- 17.4%, respectively; P = 0.029), 24 h (48.7 +/- 20.5 vs 25.0 +/- 17.6%, respectively; P = 0.035) and 72 h (45.5 +/- 15.2 vs 26.5 +/- 15.8%, respectively; P = 0.030) after clopidogrel administration. 4. In conclusion, CYP2C19*2 and CYP2C19*3 genetic polymorphisms reduced clopidogrel inhibition of ADP-induced platelet aggregation, with the degree of inhition dependent on the genetic polymorphism present.
Clinical and Experimental Pharmacology and Physiology 04/2008; 35(8):904-8. · 1.85 Impact Factor
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ABSTRACT: RNA interference (RNAi) is the most exciting insight in biology in past decades, which provided new perspectives into the genome-wide surveys of gene function by targeted degradation of mRNA with the introduction of small interfering RNAs (siRNAs) or small hairpin RNAs (shRNAs) in a large variety of organisms, and turned out to be a more efficient and convenient method compared with the traditional knockout pathway. What's more, as the enhancement of its stability and improvement of its delivery vehicles, RNAi is bound to be a practical tool in determine gene function first in vitro and then in vivo. In this paper, we will focus on the recent achievements of RNAi and also depict the development of RNAi as a potentially powerful tool in studying bone-related diseases.
Biochemical and Biophysical Research Communications 11/2007; 361(4):817-21. · 2.48 Impact Factor
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ABSTRACT: During the last 10 years, we have witnessed major progress in skeleton biology. Runx2 is an accepted transcription factor essential for osteoblast development from mesenchymal stem cells and maturation into osteocytes and organize crucial events during bone formation. Alternations in Runx2 expression levels are associated with skeletal diseases. In vitro and in vivo studies have reported that multiple integrated complex path ways (such as Wnt/LRP5/beta-catenin, BMP/Smads, 1, 25-(OH)2-vitaminD3/VDR/VDRE pathway, etc.) and several regulatory proteins (such as Msx2, Dlx5, Twists, etc.) play critical roles in modulating Runx2 gene expression, activity, and the subsequent bone formation. These findings provide novel insights through controlling osteoblast differentiation to treat osteoporosis or other bone diseases with altered bone mass by stimulating Runx2 expression. Further studies have shown that expression of RUNX2 is initiated from two promoters, the distal P1 promoter and the proximal P2 promoter. The alternative use of promoters gives rise to the genesis of two major protein isoforms with distinct amino termini, named as Runx2-TypeI and Runx2-TypeII. Here, we also review a complex spatio-temporal pattern of two major isoforms expressions and their possible function differences in skeleton development.
Medical Hypotheses 02/2007; 68(1):169-75. · 1.39 Impact Factor
