Common features of γδ T cells and CD8+ αβ T cells responding to human cytomegalovirus infection in kidney transplant recipients

Abstract

Background: Kidney transplant recipients infected with cytomegalovirus (CMV) undergo a persistent γδ T cell expansion in their peripheral blood. The anti-CMV function of these cells was previously demonstrated by their ability to kill CMV-infected cells in vitro. Methods: To gain insight into the role of γδ T cells within the antiviral immune network, we compared the expansion kinetics of these T cells with that of CMV pp65-specific CD8 + αβ T cells in the peripheral blood of twenty-one kidney transplant recipients. Results: Both the percentage and the absolute number of pp65-specific CD8+ T cells and γδ T cells showed a concomitant increase and persistence in most of the kidney transplant recipients with CMV infection. Both cell subsets exhibited an effector/memory phenotype (CD28-, CD27-, and CD45RA+) that predominated for the entire follow-up period. Conclusions: In conclusion, CMV-specific CD8+ αβ T cells and γδ T cells share common expansion kinetics and a common effector phenotype, suggesting that these cell types act similarly in response to CMV infection. © 2009 by the Infectious Diseases Society of America.