title: MICA and recovery from hepatitis C virus and hepatitis B virus infections.
abstract: The polymorphic MHC class I chain-related A (MICA) gene encodes a ligand that has different binding affinities for the NKG2D activating receptor of CD8+ T cells and natural killer (NK) cells. We hypothesized that MICA heterogeneity would affect recovery from hepatitis C virus (HCV) and hepatitis B virus (HBV) infections. To test the hypothesis, we initially typed known MICA polymorphisms for 228 persons who cleared HCV infection and 442 persons with persistent hepatitis C matched on other factors affecting viral persistence. Although MICA(*)015 was detected more than two-fold more often in persons with viral clearance (odds ratio 0.36, 95% confidence interval=0.19, 0.80), it occurred in fewer than 5% of the study population. In a similar analysis of 442 persons with chronic hepatitis B and 768 matched controls who recovered, MICA(*)015 was detected in 2.0% of persons with chronic hepatitis B and only 0.9% of controls. No significant associations were detected with other MICA polymorphisms. While further investigation may reveal a structural basis of the MICA(*)015 associations, these data provide little support for the hypothesis that differential distribution of MICA alleles substantially affects recovery from HCV and HBV infections.
authors.affiliation: Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21231, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Karacki
authors.forename: X
authors.initials: X
authors.lastname: Gao
authors.forename: C L
authors.initials: CL
authors.lastname: Thio
authors.forename: D L
authors.initials: DL
authors.lastname: Thomas
authors.forename: J J
authors.initials: JJ
authors.lastname: Goedert
authors.forename: D
authors.initials: D
authors.lastname: Vlahov
authors.forename: R A
authors.initials: RA
authors.lastname: Kaslow
authors.forename: S
authors.initials: S
authors.lastname: Strathdee
authors.forename: M W
authors.initials: MW
authors.lastname: Hilgartner
authors.forename: S J
authors.initials: SJ
authors.lastname: O'Brien
authors.forename: M
authors.initials: M
authors.lastname: Carrington
mesh_terms: D016174:Hepacivirus / Q000276:immunology / Q000378:metabolism; D006509:Hepatitis B / Q000276:immunology / Q000378:metabolism*; D006515:Hepatitis B virus / Q000276:immunology / Q000378:metabolism; D006526:Hepatitis C / Q000276:immunology / Q000378:metabolism*; D015395:Histocompatibility Antigens Class I / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D055655:NK Cell Lectin-Like Receptor Subfamily K; D011110:Polymorphism, Genetic; D011971:Receptors, Immunologic / Q000378:metabolism; D055607:Receptors, Natural Killer Cell
chemical_list: D015395:Histocompatibility Antigens Class I; C527085:KLRK1 protein, human; C099187:MHC class I-related chain A; D055655:NK Cell Lectin-Like Receptor Subfamily K; D011971:Receptors, Immunologic; D055607:Receptors, Natural Killer Cell