Circadian variations and prednisolone-induced alterations of circulating lymphocyte subsets in man

We determined the circadian variations and prednisolone (PSL)-induced alterations of circulating lymphocyte subsets in 10 healthy adults by two-color flow cytometry using monoclonal antibodies to various lymphocyte subsets in order to collect fundamental data for monitoring of the subsets in clinical practice. This study first examined the changes of CD5+ B cells, gamma delta+ or gamma delta-T cells, activated (HLA-DR+) CD4+ or CD8+ cells, CD11b+ or CD11b-CD8+ cells, and natural killer (NK) cell subsets (CD16+CD57-, CD16+CD57+, CD16-CD57+), in addition to other subsets described before. Compared with the base line values obtained at 9:00 (AM) on day 1, lymphocytes, total B cells, CD5+ B cells, total T cells, gamma delta-T cells, CD4+ cells, activated CD4+ cells, CD45RA-CD4+ cells, and activated CD8+ cells were significantly increased at 20:00 (PM). However, the numbers of CD45RA+CD4+ cells, CD11b+ or CD11b-CD8+ cells and three NK cells subsets did not show significant circadian variations. After oral PSL (30 mg), which was given at 7:00 (AM) on day 2, lymphocytes and almost all lymphocyte subsets, except for CD16+CD57- cells, were significantly decreased; these changes recovered between 13 and 26 hours after PSL administration. The circadian variations and PSL-induced alterations of lymphocyte subsets were relatively comparable, but PSL administration cause a decrease in a wider range of lymphocyte subsets including relatively corticosteroid-resistant subsets such as CD45RA+CD4+ cells, CD8+ cell and NK cell subsets.(ABSTRACT TRUNCATED AT 250 WORDS)