Objective:To investigate the effects of RNA interference(RNAi)-mediated silencing of Peroxiredoxin 1(PRDX1)gene on the invasion and migration of human colorectal cancer SW480 cells.Methods: Lentiviruses negative control vector and PRDX1 RNAi were transfected respectively into colorectal cancer SW480 cells.The transfected cells were divided into PRDX1 silencing group(si-PRDX1)and negative control group(Vector).The expressions of PRDX1 mRNA and protein in SW480 cells were exa mined by quantitative real-time PCR(qRT-PCR)and immunoblotting(Western blot),respectively.The cell migration and invasion capabilities were evaluated with transwell chamber assay and transwell chamber,respectively.The protein expressions of TIMP-2,MMP-2 and MMP-9 were detected by Western blot.Results: Compared with control group,the expressions of PRDX1 mRNA and protein were significantly decreased in PRDX1 silencing group(P<0.01),PRDX1 gene silencing cell line was successfully constructed.The levels of invasion and migration capacities of SW480 cells transfected with si-PRDX1 were lower than those in the cells transfected with control-siRNA(vector)(P<0.01).The expression of TIMP-2 was significantly increased,while the expressions of MMP-2 and MMP-9 were significantly decreased(P<0.05).Conclusion: Silencing of PRDX1 inhibits the invasion,migration and metastasis of human colorectal cancer SW480 cells by regulating the expressions of TIMP-2,MMP-2 and MMP-9.

CD4+CD25+ Regulatory T cells (Treg) have been found to down-regulate immune activation in HIV-1 infection. However, whether the depletion of Treg benefits to the disease status of HIV infection remains undefined. To address this issue, we enumerated the Treg absolute counts and frequency in 75 antiviral-na(i)ve HIV-1-infected individuals in this study. It was found that HIV-infected patients displayed a significant decline in Treg absolute counts but a significant increase in Treg frequency. In addition, with disease progression indicated by CD4 T-cell absolute counts, circulating Treg frequency gradually increased; while Treg absolute counts were gradually decreased, suggesting that the alteration of Treg number closely correlated with disease progression in HIV infection.Functional analysis further showed that Treg efficiently inhibit both CD4 and CD8 T cell proliferation in vitro. Thus, our findings indicates that Treg actively participate in pathogenesis of chronic HIV infection,influencing the disease progression.

Objective:To construct the pET30a-EgG1Y162-2 prokaryotic expression plasmid and induce the expression of EgG1Y162-2 protein, so as to provide a research basis for development of Echinococcus granulosus vaccine. Methods:Using Echinococcus granulosus cDNA as a template, the target gene of EgG1Y162-2 was synthesized by PCR, and after digestion with restriction enzymes EcoRⅠ and Hind Ⅲ, it was connected to the prokaryotic expression vector pET30a to construct the recombinant plasmid pET30a-EgG1Y162-2. The recombinant plasmid was transformed into competent cell BL21 (DE3) and induced by isopropyl β-D-thiogalactoside (IPTG) to express a large number of proteins. The recombinant protein was purified by affinity chromatography. The purification level was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and the expression product was identified by Western blotting. Results:The recombinant plasmid pET30a-EgG1Y162-2 was successfully constructed. After inducting expression, the bacterial supernatant and the eluate were both at a relative molecular weight of about 15 × 10 3, and the protein antigen component eluted with 200 mmol/L imidazole was relatively pure. Western blotting results showed that the purified recombinant protein EgG1Y162-2 with His tag could be recognized by His monoclonal antibody. Conclusion:The pET30a-EgG1Y162-2 prokaryotic expression plasmid of Echinococcus granulosus is successfully constructed, and the recombinant protein of EgG1Y162-2 is induced to express, laying a foundation for further study on anti- Echinococcus granulosus vaccine.