[Effects of miR-122 on expression of hepatitis B virus proteins].

OBJECTIVE: To investigate the effect of miR-122 on the expression of hepatitis B virus (HBV) proteins. METHODS: Anti-sense oligodeoxynucleotide (ASODN) of two different sequences against miR-122, anti-miR-122 and LNA-antimiR-122 (Locked nucleic acid), human miR -122 (hsa-miR-122), or the negative control anti-GFP were designed and synthesized, then transfected into HepG2.2.15 cells. After 24 h and 48 h, the levels of HBsAg and HBeAg in the supernatant were determined with a time-resolved immunofluorometric assay (TRFIA). HBV DNA in supernatant and miR-122 in cells were measured by quantitative real-time PCR. RESULTS: After 48 h expressions of miR-122 in the LNA-antimiR-122 and anti-miR-122 groups were significantly suppressed and lower than those in the negative control (P<0.001), while the level of miR-122 in the hsa-miR-122 group was higher than that in the negative control (P<0.001). The expression of HBeAg and HBsAg in hsa-miR-122 group was lower than that in the negative control (P<0.01) 24 h and 48 h after transfection. The expression of HBeAg and HBsAg in the anti-miR-122 group and LNA-antimiR-122 group was significantly lower than that in negative control (P>0.001). The levels of viral DNA at both time-points in the various test groups were not significantly different from those of negative control group (P>0.05). CONCLUSION: miR-122 may regulate HBV antigens and potentially affect the progress of pathogenesis, which might be the new targets for treatment of HBV infection.

Surveillance of viral contamination of invasive medical instruments in dentistry.

OBJECTIVE: To investigate the viral contamination of invasive medical instruments in dentistry and to provide health administrative institutions with surveillance data. METHODS: Sterilized samples were randomly collected from the department of dentistry to detect HBV-DNA, HCV-RNA, HIV-RNA and HBsAg. RESULTS: Of the invasive medical instruments that were sterilized with 2% glutaraldehyde, one of the samples was positive for HBV-DNA, and another sample was positive for HBsAg. CONCLUSION: Though massive virus contamination of invasive medical instruments in dentistry has been reduced to a low level, the occurrence of contamination still remains.

[Inhibition of hepatitis B virus S gene and C gene expression by different 10-23 DNAzymes substrate-recognition domains].

OBJECTIVE: To explore the inhibition effects of 10-23 DNAzymes with different substrate-recognition domains targeting hepatitis B virus (HBV) S gene and C gene expression in 2.2.15 cells. METHODS: 10-23 DNAzymes with different substrate-recognition domains specific to HBV S gene open reading frame (ORF) A(157)UG and HBV C gene ORF A(1816)UG were designed and synthesized, respectively. Different 10-23 DNAzymes were transfected into 2.2.15 cells which is a stable HBV producing cell line. HBsAg and HBeAg secreted into culture media were detected by radioimmunoassay (RIA) and HBV DNA levels were measured by real-time PCR. 3-(4, 5-dimethylthiagol-2-yl)-2, 5-drphnyl tetrazolium bromide (MTT) assays were performed to evaluate cytotoxicity. RESULTS: HBsAg and HBeAg expressions were reduced by various DNAzymes (0.1 - 2.5 micromol/L) with different substrate-recognition domains after transfection. The antiviral effects of DNAzymes were apparent until 72 h post-transfection. The inhibition rates of the DNAzymes at the same dose on HBsAg and HBeAg in the same period of post-transfection were as the following: DrzBS-9 > DrzBS-8 > DrzBS-7; DrzBC-9 > DrzBC-8 > DrzBC-7. Among all the DNAzymes used, DrzBS-9 targeting S gene and DrzBC-9 targeting C gene were most potent, with HBsAg and HBeAg reduced 95% and 92% 48 h post-transfection at the dose of 2.5 micromol/L, respectively. The inhibition effects on HBV DNA by various DNAzymes with different substrate-recognition domains were of no significance. There were no evident cytotoxic effects of these DNAzymes in the range from 0.1 to 2.5 micromol/L. CONCLUSION: 10-23 DNAzymes with different substrate-recognition domains targeting HBV S gene and C gene mRNA possessed specific inhibition effects in 2.2.15 cells, and DrzBS-9 targeting S gene and DrzBC-9 targeting C gene were most potent.

Association of cytomegalovirus infection with human leukocyte antigen genotypes in recipients after allogeneic liver transplantation.

BACKGROUND: Cytomegalovirus (CMV) infection is the important cause affecting the survival rate and function of the transplanted organ after transplantation. The occurrence of CMV infection after liver transplantation (LT) is associated with many factors. Lots of studies suggest that genetic mutation between hosts and CMV may play a role in the occurrence and development of CMV infection. CMV exists in an incubative state, affect or destroy the expression of human leukocyte antigen (HLA) molecules in the host cell surface, and interfere antigen's submission. This mechanism is the key of CMV to avoid immune defense mechanism of the host. To detect HLA and CMV antibody (CMV-Ab), CMV antigen (CMV-Ag) of transplantation recipients, we evaluated the association of CMV infection and the particular HLA genotypes in recipients after LT. METHODS: 277 blood samples were collected from 39 LT recipients. CMV antibody and antigen were detected by ELISA or immunohistochemical methods. The HLA types of the recipients were determined by PCR. To analyze the association of HLA alleles and the occurrence of CMV antigenemia in the patients, relative risk degree (RR) was used as the parameter for the Chi-square test. RESULTS: The LT recipients were serum CMV IgG positive (100%), but none of them was CMV IgM positive (0%). Thirty-three LT recipients (84.6%) were CMV antigenic positive with 1-50 positive leukocytes per 50,000 leukocytes in extent and 7.2+/-4.2 positive leukocytes per 50,000 leukocytes on average. Thirteen patients developed CMV pneumonia, with CMV antigenic positive (100%) and 17.7+/-5.5 positive leukocytes per 50,000 leukocytes on average. Some HLA alleles were associated with the occurrence and extent of CMV antigenemia. HLA-A2 was the higher frequency allele for patients with antigenemia (P<0.05), and 7 patients carrying HLA-DR11 allele developed antigenemia (P<0.05). In the lower antigenemia group, HLA-A11 was higher in frequency than others (P<0.05). Besides, none of the patients carrying HLA-B16 allele developed clinical symptoms of CMV infection (P<0.05). CONCLUSIONS: The variability of HLA alleles might modulate immune response to CMV infection. HLA examination before transplantation should be made for prevention and treatment of CMV infection after operation.