Human cytomegalovirus (CMV)-specific CD8+ T cell responses are reduced in HIV-infected individuals with a history of CMV disease despite CD4+ T cell recovery

Cytomegalovirus (CMV)-specific immunity was investigated in human immunodeficiency virus (HIV)-infected individuals. A case-control (1:2) study was performed with cases defined as having a history of CMV end-organ disease (n = 15) and controls (n = 30) matched by current CD4+ T cell count. CMV-specific CD8+ T cells responses were quantified using the high throughput Quantiferon®-CMV test (Cellestis, Melbourne, Australia). 40/44 (91%) had a positive Quantiferon®-CMV test and the magnitude of response to CMV peptides correlated significantly with response to mitogen (p < 0.0001) but not with CD4+ T cell count at the time of testing, CD4+ T cell nadir or HIV viral load. Cases had a significantly lower Quantiferon®-CMV test than controls but there was no significant difference in response to mitogen or other antigens. In individuals with a history of CMV disease, CMV-specific CD8+ T cell responses are reduced even in the setting of CD4+ T cell reconstitution.