Lymphokines and aging: interleukin-2 production and activity in aged animals.
The capacity of aged animals to produce and respond to the T cell-replacing factor, interleukin-2 (IL-2), has been examined. IL-2 activity in the supernatants of concanavalin A-activated aged spleen cells is 5- to 10-fold lower than comparable supernatants prepared using young spleen cells. This lesion in IL-2 synthesis may limit antibody production to T-dependent antigens, because supplementation with purified IL-2 markedly enhances the number of anti-SRBC plaques generated by aged spleen cells. The response of aged splenocytes can be fully restored to that obtained using young adult cells. However, there appears to be a defect in the ability of aged cells to effectively translate the IL-2 signal into B cell helper activity, in the absence of T lymphocytes. That is, although young adult, nylon wool-purified T cells can interact with aged T-depleted spleen cells, producing a normal high level anti-SRBC response, IL-2 is incapable of reconstituting the response in aged animals to this level. On the other hand, both young adult T cells and IL-2 can interact with young adult T-depleted splenic lymphocytes to produce a normal, high level anti-SRBC response.
D000375:Aging; D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D003165:Complement System Proteins; D003208:Concanavalin A / Q000494:pharmacology; D007106:Immune Sera / Q000494:pharmacology; D007376:Interleukin-2 / Q000096:biosynthesis* / Q000494:pharmacology; D008222:Lymphokines / Q000096:biosynthesis*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012756:Sheep; D013154:Spleen / Q000166:cytology; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism
D007106:Immune Sera; D007376:Interleukin-2; D008222:Lymphokines; D003208:Concanavalin A; D003165:Complement System Proteins