| First Author | Tong J | Year | 2004 |
| Journal | J Exp Med | Volume | 199 |
| Issue | 9 | Pages | 1277-83 |
| PubMed ID | 15117976 | Mgi Jnum | J:94033 |
| Mgi Id | MGI:3510556 | Doi | 10.1084/jem.20021602 |
| Citation | Tong J, et al. (2004) CD43 regulation of T cell activation is not through steric inhibition of T cell-APC interactions but through an intracellular mechanism. J Exp Med 199(9):1277-83 |
| abstractText | CD43 is a large heavily glycosylated protein highly expressed on T cells and actively excluded from the immunological synapse through interactions with ezrin-radixin-moesin proteins. Due to its size and charge, it has been proposed that the CD43 ectodomain acts as a physical barrier to T cell-APC interactions. We have addressed this hypothesis by studying the effect of reconstituting CD43 mutants into the hyperproliferative CD43(-/-) T cells. Reintroduction of full-length CD43 reversed the CD43(-/-) T cell hyperproliferation. Interestingly, despite the lack of exclusion from the interaction site, a mutant containing the CD43 ectodomain on a glycosylphosphatidylinositol linkage was ineffective. Additionally, T cell-APC conjugate formation was not affected by this ectodomain-only construct. In contrast, CD43(-/-) T cell hyperproliferation was reversed by an intracellular-only CD43 fused to the small ectodomain of hCD16. Mutation of this intracellular-only CD43 such that it could not move from the T cell-APC contact site had no further affect on proliferation than the moveable CD43 but did dramatically reduce interleukin-2 production. Thus, the exclusion of the CD43 intracellular region from the immunological synapse is required for CD43 regulation of interleukin-2 production, but the presence of the cytoplasmic tail, independent of its location, is sufficient to reverse CD43(-/-) T cell hyperproliferation. |
