|
|
||||||||
The Journal of Immunology, Vol 129, Issue 6 2360-2367, Copyright © 1982 by American Association of Immunologists
ARTICLES |
GA Dos Reis and EM Shevach
We have studied the effects of the immunosuppressive agent cyclosporin A (CY A) on T cell activation in the guinea pig both in the presence and in the absence of exogenous interleukin 2 (IL 2). CY A suppressed T cell activation by the mitogen, concanavalin A, by blocking IL 2 production and not by blocking the induction of IL 2 receptors. In contrast, the primary T cell proliferative responses to self-Ia antigens in the syngeneic mixed leukocyte reaction (SMLR) and to trinitrophenyl-modified syngeneic macrophages were blocked by CY A and this suppressive effect could not be corrected by addition of exogenous IL 2. T cells primed to syngeneic stimulator cells in the presence of CY A failed to develop IL 2 responsiveness even in the presence of exogenous IL 2, suggesting that CY A directly blocked induction of IL 2 receptors on the responding T cell population. In contrast, the secondary SMLR was suppressed by CY A in the absence of IL 2, but was normal when IL 2 was added to the cultures. CY A completely blocked the primary allogeneic MLR but this inhibitory effect could be reversed when exogenous IL 2 was added to the cultures. Moreover, in the presence of exogenous IL 2, CY A had no effect on the development of IL 2 responsiveness by alloreactive T cells. In addition, CY A induced a population of radiosensitive cells with suppressor activity for the primary MLR. Thus, in the guinea pig, CY A inhibits Ti cell activation both by blocking IL 2 production as well as by inhibiting the induction of IL 2 responsiveness. These two effects occur in the same range of CY A concentrations and are differentially dominant depending on the nature of the stimulating signal and the differentiation state of the responding T cell.
This article has been cited by other articles:
![]() |
K. McIntosh and D. Drachman Induction of suppressor cells specific for AChR in experimental autoimmune myasthenia gravis Science, April 18, 1986; 232(4748): 401 - 403. [Abstract] [PDF] |
||||
![]() |
R. Handschumacher, M. Harding, J Rice, R. Drugge, and D. Speicher Cyclophilin: a specific cytosolic binding protein for cyclosporin A Science, November 2, 1984; 226(4674): 544 - 547. [Abstract] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |