Western Kentucky University
Immune System Response to High Intensity Exercise: Study 2: (Zierten) Helper T Cell Response to Supramaximal Exercise in Untrained Individuals
Institution
Western Kentucky University
Faculty Advisor/ Mentor
James Navalta
Abstract
Exercise has been shown to modulate lymphocytes. Recently, the ability of exercise to induce cell death (apoptosis) in lymphocytes has been questioned. The purpose of this investigation was to evaluate the effect of supramaximal exercise on apoptosis and cell migration in helper T cells. Subjects (N=4) completed treadmill runs at 66%, 84%, and 97% of VO2max with 5-min rest periods. After the final rest period, a run to exhaustion was completed at 110% of aerobic capacity. Blood was sampled before, immediately following, 1-hour, and 24-hour following and used for the determination of helper T count (CD4+), cell death (annexin V), and cell migration (CX3CR1). Data were evaluated as the percent difference compared to rest. Exercise resulted in a 160% increase in CD4+ cell volume compared to the baseline value, but returned to near resting values by 1-hour-post and were not different when measured at 24-hour post. CX3CR1 on CD4+ increased 260% with exercise but returned to baseline within 1-hour following exercise. Annexin V increased with exercise similar to cell volume, but remained elevated 1- hour post (212%). The CD4+ cell count response to exercise was similar to what has been reported with overall lymphocytes. The novel finding was the decrease in cell volume following exercise. Findings indicated that volume changes immediately following exercise were due primarily to helper T cell migration out of the circulation back into the lymphoid pools. However, a prolonged effect of exercise appeared to persist as cell death in this subfraction was noted at 1-hour post.
Immune System Response to High Intensity Exercise: Study 2: (Zierten) Helper T Cell Response to Supramaximal Exercise in Untrained Individuals
Exercise has been shown to modulate lymphocytes. Recently, the ability of exercise to induce cell death (apoptosis) in lymphocytes has been questioned. The purpose of this investigation was to evaluate the effect of supramaximal exercise on apoptosis and cell migration in helper T cells. Subjects (N=4) completed treadmill runs at 66%, 84%, and 97% of VO2max with 5-min rest periods. After the final rest period, a run to exhaustion was completed at 110% of aerobic capacity. Blood was sampled before, immediately following, 1-hour, and 24-hour following and used for the determination of helper T count (CD4+), cell death (annexin V), and cell migration (CX3CR1). Data were evaluated as the percent difference compared to rest. Exercise resulted in a 160% increase in CD4+ cell volume compared to the baseline value, but returned to near resting values by 1-hour-post and were not different when measured at 24-hour post. CX3CR1 on CD4+ increased 260% with exercise but returned to baseline within 1-hour following exercise. Annexin V increased with exercise similar to cell volume, but remained elevated 1- hour post (212%). The CD4+ cell count response to exercise was similar to what has been reported with overall lymphocytes. The novel finding was the decrease in cell volume following exercise. Findings indicated that volume changes immediately following exercise were due primarily to helper T cell migration out of the circulation back into the lymphoid pools. However, a prolonged effect of exercise appeared to persist as cell death in this subfraction was noted at 1-hour post.