title: The number of activating KIR genes inversely correlates with the rate of CMV infection/reactivation in kidney transplant recipients.
abstract: Viral infection is a common complication after kidney transplantation. The role of natural killer cells (NK cells) in this setting remains unknown. NK cells express activating and inhibitory killer cell immunoglobulin-like receptors (KIR). We analyzed whether activating KIR genes carried by kidney transplant-recipients influence the rate of viral infection during the first year after transplantation. In patients with a KIR A/A genotype (n = 40, KIR2DS4 only activating KIR) the rate of cytomegalovirus (CMV) infection and reactivation was 36%, as compared to 20% in transplant recipients with more than one activating KIR gene (KIR B/X genotype, n = 82, p = 0.04). Adjusting for other risk factors in Cox regression, the relative risk of B versus A genotype patients was 0.34 (95% CI 0.15-0.76, p = 0.009). The degree of protection increased with the number of activating KIR genes. Symptomatic CMV disease was only observed in four individuals, all carrying a KIR A/A genotype. As for viral infections other than CMV, and for bacterial infections, no KIR-linked protective effect could be detected. Also, graft function and the rate-rejection episodes were similar in KIR A/A and KIR B/X genotype individuals. This study supports a role for activating KIR in the control of CMV infection after kidney transplantation.
authors.affiliation: Clinic for Hematology, Department of Research, University Hospital Basel, Switzerland. sternm@uhbs.ch
authors.forename: M
authors.initials: M
authors.lastname: Stern
authors.forename: H
authors.initials: H
authors.lastname: Elsässer
authors.forename: G
authors.initials: G
authors.lastname: Hönger
authors.forename: J
authors.initials: J
authors.lastname: Steiger
authors.forename: S
authors.initials: S
authors.lastname: Schaub
authors.forename: C
authors.initials: C
authors.lastname: Hess
mesh_terms: D000328:Adult; D000368:Aged; D001739:BK Virus; D003586:Cytomegalovirus Infections / Q000209:etiology / Q000235:genetics*; D020031:Epstein-Barr Virus Infections / Q000209:etiology / Q000235:genetics; D005838:Genotype; D006084:Graft Rejection / Q000235:genetics*; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects*; D008875:Middle Aged; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics*; D027601:Polyomavirus Infections / Q000209:etiology / Q000235:genetics; D012008:Recurrence; D012306:Risk; D014412:Tumor Virus Infections / Q000209:etiology / Q000235:genetics
chemical_list: C490245:GEM protein, human; D020559:Monomeric GTP-Binding Proteins