Distress and expression of natural killer receptors on lymphocytes

Chronic distress has been associated with alterations in natural killer (NK) cell and T cell percentages and function. NK cells express inhibitory and stimulatory receptors that regulate cytotoxicity and cytokine secretion. T cells and T cells expressing CD56 (NKT cells) also express these NK-associated receptors, which are thought to serve the same function. The objective of this study was to examine the relationship between distress and expression of NK-associated receptors on NK cells, T cells, and NKT cells. Using multicolor flow cytometry and validated questionnaires, we studied twenty-nine healthy adults with a bimodal age spread. Whereas distress was related to significantly lower percentages of CD3+ T cells, it was related to significantly higher percentages of NKT cells. Distress was associated with significantly higher percentages of T cells expressing NK-associated receptors including CD94 and KIR. In contrast, distress was associated with significantly lower percentages of NK cells bearing KIR (GL183) receptors. Our findings suggest a possible role for NK-associated receptors in distress-related alterations in lymphocyte maturation, trafficking, or activity.