Identification of mutations in viral proteins involved in cell adaptation using a reverse genetic system of the live attenuated hepatitis A virus vaccine H2 strain

Article

作者: Li, Xiao-Feng ; Li, Jian ; Yan, Xiu-Li ; Li, Lin ; Zhao, Hui ; Qin, Cheng-Feng ; Wang, Hong-Jiang ; Ma, Qing-Qing

The live attenuated hepatitis A virus vaccine H2 strain was developed by passaging a wild-type H2w isolate in cell cultures. Currently, the mechanism underlying its attenuation phenotype remain largely unknown. In this study, we generated a full-length infectious cDNA clone of the H2 strain using in-fusion techniques. The recovered H2 strain (H2ic) from the cDNA clone exhibited an efficient replication in both the hepatoma cell line Huh7.5.1 and the 2BS cell line used for vaccine production, similar to the parental H2 strain. Additionally, H2ic did not cause disease in Ifnar1^-/- C57 mice, consistent with the H2 strain. To explore the cell-adaptive mutations of the H2 strain, chimeric viruses were generated by replacing its non-structural proteins with corresponding regions from H2w using the infectious cDNA clone as a genetic backbone. The chimeric viruses carrying the 3C or 3D proteins from H2w showed decreased replication in Huh7.5.1 and 2BS cell lines compared to H2ic. Other chimeric viruses containing the 2B, 2C, or 3A proteins from H2w failed to be recovered. Furthermore, there were no significant differences in disease manifestation in mice between H2ic and the recovered chimeric viruses. These results demonstrate that adaptive mutations in the 2B, 2C, and 3A proteins are essential for efficient replication of the H2 strain in cell cultures. Mutations in the 3C and 3D proteins contribute to enhanced replication in cell cultures but did not influence the attenuated phenotypes in mice. Together, this study presents the first reverse genetic system of the H2 strain and identifies viral proteins essential for adaptation to cell cultures.

2022-07-01·The Lancet Oncology

Precancerous cervical lesions caused by non-vaccine-preventable HPV types after vaccination with the bivalent AS04-adjuvanted HPV vaccine: an analysis of the long-term follow-up study from the randomised Costa Rica HPV Vaccine Trial

Article

作者: Struijk, Linda ; van Doorn, Leen-Jan ; Quint, Wim ; Sidawy, Mary K. ; Kreimer, Aimée R. ; Hu, Shangying ; Jiménez, Silvia E. ; Sierra, Mónica S ; Schiller, John T ; Pinto, Ligia A. ; Wacholder, Sholom ; Porras, Carolina ; Hildesheim, Allan ; Kreimer, Aimée R ; Lowy, Douglas R. ; González, Paula ; Kemp, Troy J. ; Carvajal, Loretto ; Rodríguez, Ana Cecilia ; Herrero, Rolando ; Stoler, Mark H. ; Cortés, Bernal ; Schiller, John T. ; Darragh, Teresa M. ; Schiffman, Mark ; Sampson, Joshua N ; Lowy, Douglas R ; Schussler, John ; Palefsky, Joel M. ; Sherman, Mark ; Shing, Jaimie Z

BACKGROUNDIn women vaccinated against human papillomavirus (HPV), reductions in cervical disease and related procedures results in more women having intact transformation zones, potentially increasing the risk of cervical lesions caused by non-vaccine-preventable HPV types, a phenomenon termed clinical unmasking. We aimed to evaluate HPV vaccine efficacy against cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and cervical intraepithelial neoplasia grade 3 or worse (CIN3+) attributed to non-preventable HPV types in the long-term follow-up phase of the Costa Rica HPV Vaccine Trial (CVT).METHODSCVT was a randomised, double-blind, community-based trial done in Costa Rica. Eligible participants were women aged 18-25 years who were in general good health. Participants were randomly assigned (1:1) to receive an HPV 16 and 18 AS04-adjuvanted vaccine or control hepatitis A vaccine, using a blocked randomisation method (permuted block sizes of 14, 16, and 18). Vaccines in both groups were administered intramuscularly with 0·5 mL doses at 0, 1, and 6 months. Masking of vaccine allocation was maintained throughout the 4-year randomised trial phase, after which participants in the hepatitis A virus vaccine control group were provided the HPV vaccine and exited the study; a screening-only, unvaccinated control group was enrolled. The unvaccinated control group and HPV vaccine group were followed up for 7 years, during which treatment allocation was not masked. One of the prespecified primary endpoints for the long-term follow-up phase was precancers associated with HPV types not prevented by the vaccine, defined as histologically confirmed incident CIN2+ events or CIN3+ events attributed to any HPV type except HPV 16, 18, 31, 33, and 45. Our primary analytical period was years 7-11. Primary analyses were in all participants with at least one follow-up visit and excluded participants with a previous endpoint (ie, modified intention-to-treat cohort). Safety endpoints have been reported elsewhere. This trial is registered with ClinicalTrials.gov, NCT00128661 and NCT00867464. The randomised, masked trial phase is completed; an unmasked subset of women in the HPV-vaccinated group is under active investigation.FINDINGSBetween June 28, 2004, and Dec 21, 2005, 7466 participants were enrolled (HPV vaccine group n=3727 and hepatitis A virus vaccine control group n=3739). Between March 30, 2009, and July 5, 2012, 2836 women enrolled in the new unvaccinated control group. The primary analytical cohort (years 7 to 11) included 2767 participants in the HPV vaccine group and 2563 in the unvaccinated group for the CIN2+ events endpoint assessment and 2826 participants in the HPV vaccine group and 2592 in the unvaccinated control group for the CIN3+ events endpoint assessment. Median follow-up during years 7 to 11 for women included for the CIN2+ events analysis was 52·8 months (IQR 44·0 to 60·7) for the HPV vaccine group and 49·8 months (42·0 to 56·9) for the unvaccinated control group. During years 7 to 11, clinical unmasking was observed with a negative vaccine efficacy against CIN2+ events attributed to non-preventable HPV types (-71·2% [95% CI -164·0 to -12·5]), with 9·2 (95% CI 2·1 to 15·6) additional CIN2+ events attributed to non-preventable HPV types per 1000 HPV-vaccinated participants versus HPV-unvaccinated participants. 27·0 (95% CI 14·2 to 39·9) fewer CIN2+ events irrespective of HPV type per 1000 vaccinated participants were observed during 11 years of follow-up. Vaccine efficacy against CIN3+ events attributed to non-preventable HPV types during years 7 to 11 was -135·0% (95% CI -329·8 to -33·5), with 8·3 (3·0 to 12·8) additional CIN3+ events attributed to non-preventable HPV types per 1000 vaccinated participants versus unvaccinated participants.INTERPRETATIONHigher rates of CIN2+ events and CIN3+ events due to non-preventable HPV types in vaccinated versus unvaccinated participants suggests clinical unmasking could attenuate long-term reductions in high-grade disease following successful implementation of HPV vaccination programmes in screened populations. Importantly, the net benefit of vaccination remains considerable; therefore, HPV vaccination should still be prioritised as primary prevention for cervical cancer.FUNDINGNational Cancer Institute and National Institutes of Health Office of Research on Women's Health.TRANSLATIONFor the Spanish translation of the abstract see Supplementary Materials section.

2012-05-01·JAIDS Journal of Acquired Immune Deficiency Syndromes

Responses to Hepatitis A Virus Vaccine in HIV-Infected Women

Letter

作者: Mary Young ; Lorie Benning ; Jennifer Canniff ; Amanda A. Allshouse ; Howard Minkoff ; Eryka L. Wentz ; Elizabeth T. Golub ; Marek Nowicki ; Adriana Weinberg ; Samantha MaWhinney ; Mardge H. Cohen ; Ruth Greenblatt

HIV-infected individuals respond poorly to vaccines including the hepatitis A virus (HAV) vaccine1-6. Previous studies enorlled mostly men and although vaccine immunogenicity does not generally vary with sex7-10, some exceptions exist11-14. Female sex hormones, estrogen and progesterone, have been implicated in down regulation of inflammatory and anti-infective immune responses15,16, including increased HIV acquisition and transmission during pregnancy and in women receiving hormonal contraceptives (HC)17-22. In vitro supplementation of estrogen and progestin attenuates antiviral and autoimmune cell-mediated responses, particularly in the context of HIV infection 23-25. Furthermore, cell-mediated immunity decreases during the menstrual cycle reaching a nadir at the peak of estrogen and progesterone secretion 26. Collectively, these data indicate that female hormones may depress T-cell mediated immunity. Less is known about the effect of female hormones on antibody production. Virtually all antiviral and some antibacterial responses are T-cell dependent and may be affected by downregulation of T-cell immunity. We evaluated the effect of hormonal contraception (HC) and of CD4 cell numbers and plasma HIV RNA load on antibody responses to HAV vaccine of HIV-infected women.

100 项与 Hepatitis A virus vaccine (Hard to Treat Diseases Inc/Zhejiang Pukang Biotechnology) 相关的药物交易

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