Trans-ancestral fine-mapping of MHC reveals key amino acids associated with spontaneous clearance of hepatitis C in HLA-DQß1.

Spontaneous clearance of acute hepatitis C virus (HCV) infection is associated with single nucleotide polymorphisms (SNPs) on the MHC class II. We fine-mapped the MHC region in European (n = 1,600; 594 HCV clearance/1,006 HCV persistence) and African (n = 1,869; 340 HCV clearance/1,529 HCV persistence) ancestry individuals and evaluated HCV peptide binding affinity of classical alleles. In both populations, HLA-DQß1Leu26 (p valueMeta = 1.24 × 10-14) located in pocket 4 was negatively associated with HCV spontaneous clearance and HLA-DQß1Pro55 (p valueMeta = 8.23 × 10-11) located in the peptide binding region was positively associated, independently of HLA-DQß1Leu26. These two amino acids are not in linkage disequilibrium (r2 < 0.1) and explain the SNPs and classical allele associations represented by rs2647011, rs9274711, HLA-DQB1∗03:01, and HLA-DRB1∗01:01. Additionally, HCV persistence classical alleles tagged by HLA-DQß1Leu26 had fewer HCV binding epitopes and lower predicted binding affinities compared to clearance alleles (geometric mean of combined IC50 nM of persistence versus clearance; 2,321 nM versus 761.7 nM, p value = 1.35 × 10-38). In summary, MHC class II fine-mapping revealed key amino acids in HLA-DQß1 explaining allelic and SNP associations with HCV outcomes. This mechanistic advance in understanding of natural recovery and immunogenetics of HCV might set the stage for much needed enhancement and design of vaccine to promote spontaneous clearance of HCV infection.

Determinants of Liver Complications Among HIV/Hepatitis B Virus-Coinfected Patients.

BACKGROUND: Hepatitis B virus (HBV) infection is a leading cause of end-stage liver disease (ESLD) and hepatocellular carcinoma (HCC) in HIV. Factors contributing to the high rates of liver complications among HIV/HBV-coinfected individuals remain unknown. SETTING: North American AIDS Cohort Collaboration on Research and Design. METHODS: We performed a retrospective cohort study among HIV/HBV-coinfected patients in 10 US and Canadian cohorts of the North American AIDS Cohort Collaboration on Research and Design that validated ESLD (ascites, spontaneous bacterial peritonitis, variceal hemorrhage, and/or hepatic encephalopathy) and HCC diagnoses from 1996 to 2010. Multivariable Cox regression was used to examine adjusted hazard ratios [aHRs with 95% confidence interval (CIs)] of liver complications (first occurrence of ESLD or HCC) associated with hypothesized determinants and with increasing durations of HIV suppression (≤500 copies/mL). RESULTS: Among 3573 HIV/HBV patients with 13,790 person-years of follow-up, 111 liver complications occurred (incidence rate = 8.0 [95% CI: 6.6 to 9.7] events/1000 person-years). Rates of liver complication were increased with non-black/non-Hispanic race [aHR = 1.76 (1.13-2.74)], diabetes mellitus [aHR = 2.07 (1.20-3.57)], lower time-updated CD4 cell count [<200 cells/mm: aHR = 2.59 (1.36-4.91); 201-499 cells/mm: aHR = 1.75 (1.01-3.06) versus ≥500 cells/mm], heavy alcohol use [aHR = 1.58 (1.04-2.39)], and higher FIB-4 at start of follow-up [>3.25: aHR = 9.79 (5.73-16.74); 1.45-3.25: aHR = 3.20 (1.87-5.47) versus FIB-4 <1.45]. HIV suppression for ≥6 months was associated with lower liver complication rates compared with those with unsuppressed HIV [aHR = 0.56 (0.35-0.91)]. CONCLUSIONS: Non-black/non-Hispanic race, diabetes, lower CD4 cell count, heavy alcohol use, and advanced liver fibrosis were determinants of liver complications among HIV/HBV patients. Sustained HIV suppression should be a focus for HIV/HBV-coinfected patients to reduce the risks of ESLD/HCC.

Jamaica's measles elimination experience

OBJECTIVES: This article describes the effort to eliminate measles from Jamaica and its impact on measles incidence. METHODS: In addition to routine measles vaccination, the Jamaican Ministry of Health implemented a strategy of a 1-time only catch-up vaccination campaign, conducted in 1991, and periodic follow-up campaigns, the first of which occurred in 1995. RESULTS: Since 1991, despite careful surveillance, no serologically confirmed indigenous cases of measles have occurred in Jamaica. CONCLUSIONS: Measles virus circulation has been interrupted in Jamaica. The Jamaican experience provides further evidence that global measles eradicaion is achievable.(AU)

Jamaica's measles elimination experience

OBJECTIVES: This article describes the effort to eliminate measles from Jamaica and its impact on measles incidence. METHODS: In addition to routine measles vaccination, the Jamaican Ministry of Health implemented a strategy of a 1-time-only catch-up vaccination campaign, conducted in 1991, and periodic follow-up campaigns, the first of which occurred in 1995. RESULTS: Since 1991, despite careful surveillance, no serologically confirmed indigenous cases of measles have occurred in Jamaica. The Jamaican experience provides further evidence that global measles eradication is achievable (Au)

HDV 16 antibody prevalence in Jamaica and the United States reflects differences in cervical cancer rates

Human papillomavirus (HPV) is widely accepted as the primary etiologic agent in the development of cervical cancer. DNA of a particular HPV type, HPV 16, is found in about half of tumors tested. Inconsistent with this causal relationship, however, population-based studies of HPV DNA prevalence have often failed to find high rates of anogenital HPV infection in countries with high cervical cancer rates. To examine this issue, we used serology to compare HPV 16 exposure in healthy volunteer blood donors in the United States (n = 278) and similar subjects from a country with 3-fold higher cervical cancer rates, Jamaica (n = 257). Jamaican sexually transmitted disease (STD) patients (n = 831) were also studied to examine in detail the relation of HPV 16 antibodies with sexual history. Serology was conducted using an ELISA employing HPV 16 virus-like particles (VLPs). Age-adjusted seroprevalence rates were greatest among male (29 percent) and female (42 percent) STD patients, intermediate in male (19 percent) and female (24 percent) Jamaican blood donors and lowest among male (3 percent) and female (12 percent) U.S. blood donors. The higher seroprevalence in women was significant, and prevalence tended to increase with age. In multivariate logistic regression, controlling for age and gender, Jamaican blood donors were 4.2-fold (95 percent CI 2.4 - 7.2) and STD patients 8.1-fold (95 percent CI 5.0 - 13.2) more likely to have HPV 16 VLP antibodies than U.S. blood donors. Among STD patients, HPV 16 antibodies were associated with lifetime number of sex partners and years of sexual activity, as well as other factors. Our data suggest that HPV 16 VLP antibodies are strongly associated with sexual behavior. Moreover, exposure to HPV 16 appears to be much greater in Jamaica than in the United States, consistent with the high rate of cervical cancer in Jamaica (Au)