First Author | Mittrücker HW | Year | 1996 |
Journal | J Exp Med | Volume | 183 |
Issue | 6 | Pages | 2481-8 |
PubMed ID | 8676068 | Mgi Jnum | J:33610 |
Mgi Id | MGI:81088 | Doi | 10.1084/jem.183.6.2481 |
Citation | Mittrucker HW, et al. (1996) Induction of unresponsiveness and impaired T cell expansion by staphylococcal enterotoxin B in CD28-deficient mice. J Exp Med 183(6):2481-8 |
abstractText | We used CD28-deficient mice to analyze the importance of CD28 costimulation for the response against Staphylococcal enterotoxin B (SEB) in vivo. CD28 was necessary for the strong expansion of V beta 8+ T cells, but not for deletion. The lack of expansion was not due to a failure of SEB to activate V beta 8+ T cells, as V beta 8+ T cells from both CD28-/- and CD28+/+ mice showed similar phenotypic changes within the first 24 h after SEB injection and cell cycle analysis showed that an equal percentage of V beta 8+ T cells started to proliferate. However, the phenotype and the state of proliferation of V beta 8+ T cells was different at later time points. Furthermore, in CD28-/- mice injection with SEB led to rapid induction of unresponsiveness in SEB responsive T cells, indicated by a drastic reduction of proliferation after secondary SEB stimulation in vitro. Unresponsiveness could also be demonstrated in vivo, as CD28-/- mice produced only marginal amounts of TNF alpha after rechallenge with SEB. In addition CD28-/- mice were protected against a lethal toxic shock induced by a second injection with SEB. Our results indicate that CD28 costimulation is crucial for the T cell-mediated toxicity of SEB and demonstrate that T cell stimulation in the absence of CD28 costimulation induces unresponsiveness in vivo. |