ABSTRACT
<p><b>OBJECTIVE</b>To detect humoral immune response against different function regions of hepatitis C virus (HCV) in chronic patients, and further to investigate the correlativity between anti-HCV antibody titers and HCV RNA concentration.</p><p><b>METHODS</b>Using recombinant dominate epitope antigens, e.g. HCV Core, NS3, NS4, NS5 and chimeric HVR1, a set of ELISA test reagents was formulated. Then, titers of antibodies against HCV different regions and the RNA concentration of HCV in chronic patient sera were detected by ELISA and quantitative RT-PCR technique, respectively.</p><p><b>RESULTS</b>Great differences have been noted in antibody titers and positive rate of different HCV function regions in chronic patients. Antibodies against HCV Core and HVR1 have the highest positive rate, then NS3, NS4, and NS5 in sequence.</p><p><b>CONCLUSION</b>The titer of antibodies against different regions of HCV in chronic patients has good correlation with HCV RNA concentration.</p>
Subject(s)
Humans , Hepatitis C Antibodies , Blood , Hepatitis C, Chronic , Allergy and Immunology , Virology , RNA, Viral , BloodABSTRACT
In order to reach the purpose of co-transferring double drug resistance genes into human CD34(+) progenitor cells to broaden the spectrum of drug resistance, the expression efficiency of human multidrug resistance 1 (MDR1) gene mediated by the internal ribosomal entry site (IRES) was investigated. Two retroviral vectors were transferred into packaging cells. One is pSF-DIM containing double drug resistance genes, in which the translation of MDR1 gene was controlled under an IRES from encephalomyocarditis virus. The other is pSF-MDR1 which only contains MDR1 gene controlled under the same promoter of pSF-DIM. The amphotropic retroviral packaging cells PA317/pSF-DIM and PA317/pSF-MDR1 were obtained with titer of 8 x 10(4) and 1.3 x 10(5) cfu/ml respectively. Human cord blood CD34(+) cells were transduced by supernatant infection. Expression of P-gp was detected by flow cytometry. Compared with the untransduced group, the expression of P-gp in pSF-DIM transduced group and pSF-MDR1 transduced group was elevated 10.92% and 28.82% respectively. However, the expression of P-gp in pSF-MDR1 transduced group was higher than that in pSF-DIM transduced group. The result suggests that MDR1 gene can express in the human progenitor cells under control of IRES. It laid the foundation of subsequence research. The reason on the difference in MDR1 gene expression efficiency between pSF-MDR1 transduced group and pSF-DIM transduced group need further research.
ABSTRACT
CD40/CD40L interactions play a pivotal role in T cell activation, and take part in many physiologic and pathologic procedures and different levels. In this article, stable CHO transformants secreting human CD40-Ig fusion protein were established through transfection and selection with Lipofectamaine and G418, respectively. In order to obtain great valume of recombinant protein, big batch serum-free cultures of engineered CHO cells were performed in roller-bottle using CHO-II-SFM medium. After cultures, the cell-culture supernatants were harvested, concentrated through ultra-filtration, and finally purified by affinity choromatography with Protein G Sepharose Fast Flow. Human peripheral bloods were collected freshly and seperated with Ficoll, CFU-T was cultured in semi-solid culture system with peripheral blood mononuclear cells (PBMNC). Effect of human CD40-Ig fusion protein on the formation of CFU-T was observed in vitro. The results showed that the yield of human CD40-Ig fusion protein was 30 mg in total 3 liter CHO-II-SFM culture supernatant, and it supposed that the expression level of CD40-Ig in CHO cells was more than 10 micro g/ml. The purity of purified fusion protein is above 95%. Furthermore, compared with human IgG, human CD40-Ig fusion protein significantly inhibited the formation of CFU-T at dose 0.25, 1.0, 4.0, and 10 micro g/ml, it lays a good foundation to evaluate its potential functions in vivo.