AIM: To determine whether HBV with the same characteristics causes dissimilar mutations in different hosts. METHODS: Full-length HBV genome was amplified and linked with pMD T18 vector. Positive clones were selected b...AIM: To determine whether HBV with the same characteristics causes dissimilar mutations in different hosts. METHODS: Full-length HBV genome was amplified and linked with pMD T18 vector. Positive clones were selected by double-restriction endonuclease digestion (EcoRⅠ and HindⅢ) and PCR. Twenty seven clones were randomly selected from an asymptomatic mother [at two time points: 602 (1 d) and 6022 (6 mo)] and her son [602 (S)], and the phylogenetic and mutational analysis was performed using BioEditor, Clustal X and MEGA software. Potential immune epitopes were determined by the Stabilized Matrix Method (SMM), SMM-Align Method and Emini Surface Accessibility Prediction. RESULTS: All of the 27 sequences were genotype C, the divergence between the mother and son was 0%-0.8%. Compared with another 50 complete sequences of genotype C, the mother and her son each had 13 specific nucleotides that differed from the other genotype C isolates. AA 1-11 deletion in preS1 was the dominant mutation in the mother (14/18). The 1762T/1764A double mutation existed in all clones of the mother, 3 of them were also coupled with G1896A mutation, but none were found in the son.17 bp deletion starting at nucleotide 2330 was the major mutation (5/9) in the son, which caused seven potential HLA class Ⅰ epitopes and one B cell epitope deletion, and produced a presumptive new start codon, downstream from the original one of the P gene. CONCLUSION: The HBV strain in the son came from his mother, and discrepant mutation occurred in the mother and her son during infection.展开更多
OBJECTIVE: To study the effect and mechanism of the peripheral blood mononuclear cell (PBMC) invasion by HBV on artificial immunization in newborns. METHODS: Fifty-two newborns of HBsAg positive mothers were immunized...OBJECTIVE: To study the effect and mechanism of the peripheral blood mononuclear cell (PBMC) invasion by HBV on artificial immunization in newborns. METHODS: Fifty-two newborns of HBsAg positive mothers were immunized with HBIG (hepatitis B immunoglobulin) and HBVac (hepatitis B vaccine) and were followed up for 7 months. The newborns' HBV-DNA in serum and in the PBMCs was detected with nested-PCR; anti-HBs was tested with solid phase radioimmunoassay (SP-RIA). PBMCs isolated from newborn peripheral blood were incubated in the presence of PHA or purified HBsAg. Interleukin-2 (IL-2) level in culture supernatants of activated cells was detected by ELISA. RESULTS: The failure rate of immunization was higher in infants with positive HBV-DNA in PBMCs than those with negative HBV-DNA (P展开更多
To study the effect of different delivery modes on immunoprophylaxis efficacy so as to clarify whether or not cesarean section reduces immunoprophylaxis failure Methods Mothers with positive hepatitis B surface ant...To study the effect of different delivery modes on immunoprophylaxis efficacy so as to clarify whether or not cesarean section reduces immunoprophylaxis failure Methods Mothers with positive hepatitis B surface antigen (HBsAg) were selected in the third trimester of pregnancy Their babies were inoculated with hepatitis B immunoglobulin at birth and hepatitis B vaccine at 1, 2 and 7 months of age HBsAg and its antibodies (anti HBs) were tested at 1, 4, 7, and 12 months of age, then followed up yearly Results A total of 301 babies entered the study, including 144 born by normal spontaneous vaginal delivery, 40 by obstetric forceps or vacuum extraction, and 117 by cesarean section The incidence of mother’s HBeAg positivity or baby’s gender constitution was comparable between the three groups There were no significant differences in the positive rate of anti HBs or HBsAg at follow up periods among the three groups At 12 months of age, anti HBs could be detected in 78 9% of the babies born by normal vaginal delivery, 84 6% of the babies by forceps or vacuum extraction, and 86 4% of the babies by cesarean section The positive rate of HBsAg was 8 1%, 7 7%, 9 7%, and chronic HBV infection incidence was 7 3%, 7 7%, 6 8% respectively Conclusions There are no significant effects of delivery mode on the interruption of HBV maternal baby transmission by immunoprophylaxis Cesarean section does not reduce the incidence of immunoprophylaxis failure展开更多
基金The Natural Science Foundation of Yunnan Province, No.200300172Hospital Science Foundation of The First People’s Hospital of Yunnan Province (2004)
文摘AIM: To determine whether HBV with the same characteristics causes dissimilar mutations in different hosts. METHODS: Full-length HBV genome was amplified and linked with pMD T18 vector. Positive clones were selected by double-restriction endonuclease digestion (EcoRⅠ and HindⅢ) and PCR. Twenty seven clones were randomly selected from an asymptomatic mother [at two time points: 602 (1 d) and 6022 (6 mo)] and her son [602 (S)], and the phylogenetic and mutational analysis was performed using BioEditor, Clustal X and MEGA software. Potential immune epitopes were determined by the Stabilized Matrix Method (SMM), SMM-Align Method and Emini Surface Accessibility Prediction. RESULTS: All of the 27 sequences were genotype C, the divergence between the mother and son was 0%-0.8%. Compared with another 50 complete sequences of genotype C, the mother and her son each had 13 specific nucleotides that differed from the other genotype C isolates. AA 1-11 deletion in preS1 was the dominant mutation in the mother (14/18). The 1762T/1764A double mutation existed in all clones of the mother, 3 of them were also coupled with G1896A mutation, but none were found in the son.17 bp deletion starting at nucleotide 2330 was the major mutation (5/9) in the son, which caused seven potential HLA class Ⅰ epitopes and one B cell epitope deletion, and produced a presumptive new start codon, downstream from the original one of the P gene. CONCLUSION: The HBV strain in the son came from his mother, and discrepant mutation occurred in the mother and her son during infection.
文摘OBJECTIVE: To study the effect and mechanism of the peripheral blood mononuclear cell (PBMC) invasion by HBV on artificial immunization in newborns. METHODS: Fifty-two newborns of HBsAg positive mothers were immunized with HBIG (hepatitis B immunoglobulin) and HBVac (hepatitis B vaccine) and were followed up for 7 months. The newborns' HBV-DNA in serum and in the PBMCs was detected with nested-PCR; anti-HBs was tested with solid phase radioimmunoassay (SP-RIA). PBMCs isolated from newborn peripheral blood were incubated in the presence of PHA or purified HBsAg. Interleukin-2 (IL-2) level in culture supernatants of activated cells was detected by ELISA. RESULTS: The failure rate of immunization was higher in infants with positive HBV-DNA in PBMCs than those with negative HBV-DNA (P
文摘To study the effect of different delivery modes on immunoprophylaxis efficacy so as to clarify whether or not cesarean section reduces immunoprophylaxis failure Methods Mothers with positive hepatitis B surface antigen (HBsAg) were selected in the third trimester of pregnancy Their babies were inoculated with hepatitis B immunoglobulin at birth and hepatitis B vaccine at 1, 2 and 7 months of age HBsAg and its antibodies (anti HBs) were tested at 1, 4, 7, and 12 months of age, then followed up yearly Results A total of 301 babies entered the study, including 144 born by normal spontaneous vaginal delivery, 40 by obstetric forceps or vacuum extraction, and 117 by cesarean section The incidence of mother’s HBeAg positivity or baby’s gender constitution was comparable between the three groups There were no significant differences in the positive rate of anti HBs or HBsAg at follow up periods among the three groups At 12 months of age, anti HBs could be detected in 78 9% of the babies born by normal vaginal delivery, 84 6% of the babies by forceps or vacuum extraction, and 86 4% of the babies by cesarean section The positive rate of HBsAg was 8 1%, 7 7%, 9 7%, and chronic HBV infection incidence was 7 3%, 7 7%, 6 8% respectively Conclusions There are no significant effects of delivery mode on the interruption of HBV maternal baby transmission by immunoprophylaxis Cesarean section does not reduce the incidence of immunoprophylaxis failure
