Cardiovascular Reactivity and the Course of Immune Response to an Acute Psychological Stressor

This study evaluated the temporal nature of cellular immune responses, as well as the effects of cardiovascular reactivity on immune responses after exposure to an acute psychological stressor. Lymphocyte subsets and lymphocyte proliferative response to phytohemagglutinin were assessed at baseline and at 5 and 21 minutes after stressor onset in the experimental group and at the same time points in a nonstressor control group. By 5 minutes after stressor onset, the number of CD8 suppressor/cytotoxic T and CD16/56 natural killer cells increased and proliferative response to phytohemagglutinin decreased. These changes were maintained at 21 minutes. Those subjects showing the greatest cardiovascular reactivity had the largest immune alterations. These data did not indicate that gender significantly moderated immune responses. Results are consistent with the hypothesis that sympathetic activation mediates stressor-induced quantitative alterations of peripheral blood lymphocyte subpopulations and nonspecific mitogen stimulated proliferation.