Cytomegalovirus Infection Impairs the Mobilization of Tissue-Resident Innate Lymphoid Cells into the Peripheral Blood Compartment in Response to Acute Exercise

Abstract

Circulating immune cell numbers and phenotypes are impacted by high-intensity acute bouts of exercise and infection history with the latent herpesviruses cytomegalovirus (CMV). In particular, CMV infection history impairs the exercise-induced mobilization of cytotoxic innate lymphoid cells 1 (ILC1) cells, also known as NK cells, in the blood. However, it remains unknown whether exercise and CMV infection modulate the mobilization of traditionally tissue-resident non-cytotoxic ILCs into the peripheral blood compartment. To address this question, 22 healthy individuals with or without CMV (20–35 years—45% CMVpos) completed 30 min of cycling at 70% VO2 max, and detailed phenotypic analysis of circulating ILCs was performed at rest and immediately post-exercise. We show for the first time that a bout of high-intensity exercise is associated with an influx of ILCs that are traditionally regarded as tissue-resident. In addition, this is the first study to highlight that latent CMV infection blunts the exercise-response of total ILCs and progenitor ILCs (ILCPs). These promising data suggest that acute exercise facilitates the circulation of certain ILC subsets, further advocating for the improvements in health seen with exercise by enhancing cellular mobilization and immunosurveillance, while also highlighting the indirect deleterious effects of CMV infection in healthy adults.

Acute Exercise Increases NK Cell Mitochondrial Respiration and Cytotoxicity against Triple-Negative Breast Cancer Cells under Hypoxic Conditions

“…Complete blood counts were determined using an automated hematology analyzer in duplicate (Sysmex XN-330; Sysmex Co., Kobe, Japan). Immediately after complete blood counting, PBMC were isolated by density gradient centrifugation as previously described (Stem Cell Technologies, Vancouver, Canada) (18). After isolation, PBMC were counted using a flow cytometer (BD Accuri C6, Ann Arbor, MI) and an automated cell counter (Countess 3 FL; ThermoFisher Scientific Inc., Waltham, MA) Then, according to the manufacturer's instructions, NK cells were isolated by negative selection using magnetic-activated cell sorting separation beads (Miltenyi Biotec, Auburn, CA).…”