title: Higher risk of cytomegalovirus reactivation in human immunodeficiency  virus-1-infected patients homozygous for MICA5.1.
abstract: Infection with cytomegalovirus (CMV) induces surface expression of major histocompatibility complex (MHC)-class-I-chain-related A (MICA), a ligand for NKG2D. This leads to improved recognition and elimination of infected cells by natural killer (NK) as well as CD8+ T cells. The MICA5.1 allele codes for a truncated protein. This study was performed to test whether impaired expression of a functional MICA protein would influence the susceptibility to severe CMV reactivation in immunocompromised individuals. In this study, the frequency of MICA5.1 was assessed by polymerase chain reaction in 230 Caucasian human immunodeficiency virus (HIV)-1-infected patients and in 219 healthy controls. Patients co-infected with hepatitis C virus (HCV) and GB virus-C served as controls. MICA5.1 allele was analyzed by polymerase chain reaction. Association of MICA5.1 homozygosity and risk of CMV reactivation was calculated by Pearson chi2 test. Comparison of patients with and without a history of CMV disease manifestation revealed that homozygous MICA5.1 genotype was present in a significantly higher frequency in patients with CMV reactivation (33%) than in those without (16%; p 0.032; odds ratio 0.330). The percentage was similar in HIV-1-infected patients and healthy controls. Furthermore, there was no difference in the frequency of MICA5.1 with respect to infection with HCV and GB virus-C. Our study provides the first in vivo demonstration of an association between homozygous MICA5.1 genotype and susceptibility to CMV reactivation in immunocompromised individuals.
authors.affiliation: Department of Clinical Immunology and Rheumatology, Hannover Medical School, Hannover, Germany.
authors.forename: Maren
authors.initials: M
authors.lastname: Moenkemeyer
authors.forename: Hans
authors.initials: H
authors.lastname: Heiken
authors.forename: Reinhold E
authors.initials: RE
authors.lastname: Schmidt
authors.forename: Torsten
authors.initials: T
authors.lastname: Witte
mesh_terms: D003587:Cytomegalovirus / Q000502:physiology*; D003586:Cytomegalovirus Infections / Q000276:immunology* / Q000821:virology; D018178:Flaviviridae Infections / Q000276:immunology* / Q000821:virology; D029407:GB virus C / Q000276:immunology* / Q000472:pathogenicity; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D016174:Hepacivirus / Q000276:immunology* / Q000472:pathogenicity; D006526:Hepatitis C / Q000276:immunology* / Q000821:virology; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006720:Homozygote; D006801:Humans; D016867:Immunocompromised Host / Q000276:immunology*; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D014775:Virus Activation; D044465:White People
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A