ABSTRACT
<p><b>OBJECTIVE</b>To study whether the abilities of hepatitis C virus (HCV) E2 gene immunization to induce humoral and cellular immune responses to E2 protein were affected by hepatitis B virus (HBV) preS gene when they fused in DNA-immunized mice.</p><p><b>METHODS</b>Mice were immunized with E2, preS-E2 (preS gene was upstream of E2 gene), and E2-preS (preS gene was downstream of E2 gene) gene by their eukaryotic expression vectors, respectively. The anti-E2 or anti-preS antibodies were detected using the E2 and preS antigens. The cellular immune response to E2 protein in immunized mice was presented by its survival time after injecting SP2/O myeloma cells expressing HCV E2 protein into the abdominal cavity.</p><p><b>RESULTS</b>Chimeric E2 and preS gene immunization can induce mice to develop anti-preS and anti-E2 antibodies. The number of the mice developing anti-E2 antibody and the antibody titers in preS-E2 gene-injected group were higher than those in E2-preS gene-immunized group. However, the mice injected with E2 gene did not develop the detectable anti-E2 antibodies until 12 weeks after DNA immunization. After the mice was injected with target cells, the average survival time of the mice in the group immunized with E2 gene alone was longer than that of the group injected with E2 gene fused with HBV preS and was significantly longer than that of the control (P < 0.05).</p><p><b>CONCLUSION</b>HBV preS might be a humoral enhancer that can affect the abilities of HCV E2 protein to induce immune responses in DNA-immunized mice.</p>
Subject(s)
Animals , Male , Mice , Antibody Formation , Hepacivirus , Chemistry , Hepatitis B Surface Antigens , Genetics , Pharmacology , Hepatitis B virus , Chemistry , Genetics , Immunity, Cellular , Mice, Inbred BALB C , Protein Precursors , Genetics , Pharmacology , Recombinant Fusion Proteins , Allergy and Immunology , Viral Envelope Proteins , Genetics , PharmacologyABSTRACT
Objective To evaluate the two methods for quantitative hepatitis B virus (HBV) DNA test. Methods The Hybrid Capture II system from Digene Co. and Real Time PCR fluorimetry quantitative HBV DNA test kit from PIJI Bio Technical Development Company Ltd. were used to detect sera HBV DNA in sera of patients with chronic hepatitis B. Results With the two quantitative methods, the positive rates of HBV DNA were 98 6% and 94.6% respectively. The concordant rate of these two methods was 93.2%. In assessing the sensitivity of the two kits with a serial of 10 fold diluted patients′s sera, PG kit could test 10 -7 of diluted serum, and HC II could test 10 -6 . The test value of HC II was more accurate in quantitation than PG kit especially in higher titer of HBV DNA. Whereas in the case of low titer of HBV DNA, the deviation of test value increased in both two methods. For monitoring the anti virus effect with quantitative HBV DNA in CHB patients, these two methods had same sensitivity, and the test value of HBV DNA had the same trend of change. Conclusion HC II system and PG test kit were sensitive and reliable, and they were worthy of monitoring the anti virus efficacy and of clinical practice.