CMV Amplifies T-cell Redeployment to Acute Exercise Independently of HSV-1 Serostatus

PURPOSELatent cytomegalovirus (CMV) infection has been shown to alter the lymphocyte response to acute aerobic exercise, likely due to the corresponding increase in exercise-responsive memory CD8 T cells. It is unknown if latent infection with another herpesvirus, herpes simplex virus 1 (HSV-1), also plays a role in shaping the lymphocyte response to exercise. METHODSThirty-two men (ages 39.3 ± 14.7 yr) counterbalanced by CMV and HSV-1 serostatus (positive/negative) cycled for 30 min at ∼80% peak power. Blood sampled before, immediately after, and 1 h after exercise was analyzed by flow cytometry for T-cell subset enumeration. RESULTSIn resting blood, HSV-1 had fewer lymphocytes, CD4 T cells, KLRG1CD28CD4 T cells, and CD45RACCR7CD4 T cells than HSV-1, whereas CMV had increased numbers of lymphocytes, CD8 T cells, KLRG1CD28CD4 and CD8 T cells, and CD45RACCR7CD8 T cells and a lower CD4:CD8 T-cell ratio than CMV. After exercise, CMV had a greater mobilization of CD8 T cells, KLRG1CD28CD4 and CD8 T cells, and CD45RACCR7CD8 T cells independently of HSV-1 serostatus, as well as a greater egress of these subsets 1 h after exercise. HSV serostatus did not influence total CD8 T-cell response to exercise. CONCLUSIONSThe impact of latent CMV infection on the redeployment of T-cell subsets with exercise is independent of HSV-1 infection. This is most likely due to the unique ability of CMV to alter the composition of the memory T-cell pool in favor of exercise-responsive T-cell subsets.