MICA and Recovery from Hepatitis C Virus and Hepatitis B Virus Infections
Genes and Immunity
HCV, HBV, MICA, Genetics, Viral persistence, Pathogenesis
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.
Karacki, Peter; Xiaojiang Gao; Chloe L. Thio; D. L. Thomas; James J. Goedert; David Vlahov; Richard A. Kaslow; Steffanie A. Strathdee; Margaret Hilgartner; Stephen J. O'Brien; and Mary Carrington. 2004. "MICA and Recovery from Hepatitis C Virus and Hepatitis B Virus Infections." Genes and Immunity 5, (4): 261-266. http://nsuworks.nova.edu/cnso_bio_facarticles/563