Expression of transforming growth factor-β1 and its receptors in peripheral blood of patients with immune thrombocytopenic purpura / 中国实验血液学杂志

This study was purposed to detect the expression of transforming growth factor β1 (TGF-β1) and its receptors (TGF-βR) and to investigate their roles in pathogenesis of immune thrombocytopenic purpura (ITP). The expressions of TGF-β1 and their receptors TGF-βRI, TGF-βRII and TGF-βRIII in the peripheral blood of patients with ITP and healthy persons were detected by the real-time PCR, and differences of their expression levels were analysed. The results showed that the expression of TGF-β1 and TGF-βRII mRNA in ITP patients was significantly higher than that in the healthy controls, while the TGF-βRI mRNA expression in ITP patient was significantly lower than that in the controls. The expression of TGF-βRIII was not statistically different between the two groups. It is concluded that TGF-β1 and its receptors including TGF-βRI and TGF-βRII express abnormally in the peripheral blood of ITP patients, which suggests that the TGF-β signaling pathway probably play a vital role in the pathogenesis of the ITP.

Anti-tumor effect of recombinant retroviral vector-mediated human ANGPTL4 gene transfection / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>This study was designed to obtain a recombinant retroviral vector containing the human hepatocellular carcinoma-related gene ANGPTL4 (angiopoietin-like 4) cDNA and to evaluate the anti-tumor effect of recombinant retroviral vector-mediated human ANGPTL4 gene transfection.</p><p><b>METHODS</b>ANGPTL4 cDNA was cloned in vitro from normal human liver cells HL-7702 by using RT-PCR, and then subcloned into the plasmid vector pMSCV and sequenced. The retroviral plasmid vectors pMSCV-ANGPTL4, pVSV, and pGAG-POL were co-transfected into the packaging cell line 293 EBNA under mediation of lipofectamine. A high-titer retrovirus was obtained as a result, and HepG2 cells were infected with this retrovirus in vitro. Flow cytometry and fluorescence microscopy were used to detect expression of green fluorescence protein (GFP). The expression of ANGPTL4 mRNA in HepG2-ANGPTL4 cells was investigated using RT-PCR. The formation of tumors in nude mice and MTT assays were used to detect the growth of HepG2-ANGPTL4 cells in vivo and in vitro, respectively.</p><p><b>RESULTS</b>The cDNA sequence of the cloned ANGPTL4 gene was consistent with the recently reported sequence. Thus, the recombinant retroviral vector pMSCV-ANGPTL4 was constructed successfully. The titer of the packaged recombinant retrovirus was 1.4 x 10(6) infective viral grains/ml, and the rate of HepG2-ANGPTL4 cells expressing GFP was 68.45%, with an average intensity of fluorescence 31.67 times greater in HepG2-ANGPTL4 cells than in HepG2 cells. The expression of ANGPTL4 mRNA in HepG2-ANGPTL4 cells was higher than in HepG2-pMSCV cells (154% higher) or HepG2 cells (161% higher). The proliferation rate of HepG2-ANGPTL4 cells in vitro was obviously lower than those of HepG2-pMSCV cells and HepG2 cells (P <0.01). The mean volume and weight of tumors seeded from HepG2-ANGPTL4 cells were obviously lower than the mean volume or weight of tumors seeded from HepG2 cells and HepG2-pMSCV cells (P <0.01).</p><p><b>CONCLUSION</b>A stable ANGPTL4-transfected human liver cancer cell line HepG2-ANGPTL4 has been created. The transfer of the human ANGPTL4 gene mediated by a retroviral vector is a possibly effective approach for liver cancer therapy.</p>