Costimulation mediated by the CD28 receptor has been shown to play an important role in the development of a vigorous T cell immune response. Nevertheless, CD28-deficient mice can mount effective T cell-dependent immune responses. These data suggest that other costimulatory molecules may play a role in T cell activation. In a search for other costimulatory receptors on T cells, we have characterized a monoclonal antibody (mAb) that can costimulate T cells in the absence of accessory cells. Similar to CD28 antibodies, this mAb, R2/60, was found to synergize with T cell receptor engagement in inducing proliferation. Independent ligation of CD3 and the ligand recognized by R2/60 results in T cell proliferation, suggesting that the two molecules do not have to colocalize to activate the R2/60 costimulatory pathway. R2/60 does not react with CD28, and furthermore, R2/60 costimulates in a CD28-independent fashion since the mAb costimulates T cells from the CD28-deficient mice as well as wild-type mice. Expression cloning of the R2/60 antigen identified the ligand as murine CD43. Together, these data demonstrate that CD43 can serve as a receptor on T cells that can provide CD28-independent costimulation.
CD43 is a murine T cell costimulatory receptor that functions independently of CD28.
- Views Icon Views
- Share Icon Share
- Search Site
A I Sperling, J M Green, R L Mosley, P L Smith, R J DiPaolo, J R Klein, J A Bluestone, C B Thompson; CD43 is a murine T cell costimulatory receptor that functions independently of CD28.. J Exp Med 1 July 1995; 182 (1): 139–146. doi: https://doi.org/10.1084/jem.182.1.139
Download citation file: