Effects of single oral doses of prednisone (PDN) on the distribution of human lymphocytes

In the present paper we analyze the effect of a single oral dose of 12 mg of prednisone (PDN) on the T lymphocyte subpopulations with a panel of monoclonal antibodies. A single oral dose of PDN induced a depletion of peripheral blood T lymphocytes as measured by the E rosette technique. Indeed the total number of E⁺ lymphocytes, with respect to the baseline value, was 32% lower after 4 hours and 50% lower after 6 hours. Eight hours after PDN the number of E⁺ cells started recovering and it reached the baseline value 24 hours after PDN. The OKT3 cells, which include the majority of T lymphocytes, behaved like the E rosette forming cells. When we looked at the OKT4 (helper) and OKT8 (suppressor), we found a quite different behaviour. The number of OKT4⁺ lymphocytes declined, as did the total T cells, while the OKT8⁺ increased slowly between the 6th and the 48th hour after PDN, at which time numbers rose above those of the OKT4⁺ population and almost doubled the baseline value. No significant changes were observed for the MbIg, Ia-like and OKM1 bearing cells. The data reported above show that corticosteroids redistribute helper and suppressor T lymphocytes as identified with monoclonal antibodies. Such an observation is in agreement with previous data indicating a similar effect on T lymphocytes bearing Fc receptor for IgM or IgG.