The effect of steroids on the circulating lymphocyte population--VI. Studies of the thoracic duct T- and B-lymphocyte populations after neonatal thymectomy and prednisolone treatment. An immunofluorescence study in the rat.
The corticosteroid effect on circulating lymphocytes in a steroid-sensitive species (rat) was studied by immunofluorescence. Both normal and neonatally thymectomized animals were injected with a high dose of prednisolone. T- and B-lymphocytes as well as T-lymphocyte subsets were analyzed in thoracic duct lymph during the involution phase (3 h after injection) and the restitution phase (17 h after injection) using conventional and monoclonal antisera. Neonatal thymectomy significantly reduced the number of circulating T-helper and T-non helper cells. In the involution phase, after a corticosteroid injection, there was a 64% reduction of lymph cell content in normal rats, affecting both T- and B-lymphocytes. Thymectomized animals showed an even more pronounced disappearance of cells. Counted in percentage, more B- than T-lymphocytes disappeared from the circulation. The T-non helper cells disappeared to a greater extent than the T-helper cells did. Cells with Ia-antigen showed about the same values as the B-lymphocytes. During the restitution phase all cells types were restored to normal levels. It seems that a high prednisolone dose has a more pronounced effect on the circulation of B- than of T-lymphocytes, and the T-non helper cells are probably more sensitive than the T-helper subpopulation. These data support the hypothesis that a major corticosteroid effect is a trapping and redistribution of circulating lymphocytes, more pronounced for certain cell types.
D000818:Animals; D000831:Animals, Newborn / Q000276:immunology*; D000918:Antibody Specificity; D000961:Antilymphocyte Serum / Q000494:pharmacology; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D005455:Fluorescent Antibody Technique; D007958:Leukocyte Count; D011239:Prednisolone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D013897:Thoracic Duct / Q000166:cytology; D013934:Thymectomy
D000961:Antilymphocyte Serum; D011239:Prednisolone