CIRCADIAN CHANGES OF LYMPHOCYTE-T SUBSETS IN HUMAN PERIPHERAL-BLOOD

  • 1 January 1984
    • journal article
    • research article
    • Vol. 55  (3) , 618-622
Abstract
The circadian variations in circulating T cell subsets defined by monoclonal antibodies in 8 healthy male volunteers were evaluated in whole blood using a flow cytometry. In all subjects, the number of lymphocytes showed a clear rhythmicity with high values at night and low values during the day. This circadian variation in circulating lymphocytes appeared to reflect largely a change in the number of T cells rather than B cells. The precentage of OKT3+ and OKT11+ cells showed a similar fluctuation with a peak at night and a depression during the day. The precentage of OKT4+ cells varied in parallel with that of T cells, particularly of OKT3+ cells but the OKT8+ subset was not appreciably altered over a 24 h period. Thus, a circadian variation of T cells could be largely accounted for by a circadian change of OKT4+ cells. Plasma cortisol levels showed an expected circadian variation. There might be an intimate relationship between these circadian changes of T cell subsets and plasma cortisol levels.