Shamshiev A, Donda A, Prigozy T I, Mori L, Chigorno V, Benedict C A, Kappos L, Sonnino S, Kronenberg M, De Libero G
Experimental Immunology, Department of Research, University Hospital, Basel, Switzerland.
Immunity. 2000 Aug;13(2):255-64. doi: 10.1016/s1074-7613(00)00025-x.
The structural basis for the T cell recognition of lipoglycans remains to be elucidated. We have described autoreactive T cells responsive to GM1 ganglioside presented by CD1b. We show that glycosphingolipids bind to CD1b on the cell surface at neutral pH and are recognized without internalization or processing. Furthermore, soluble GM-CD1b complexes stimulate specific T cells. Oligosaccharide groups containing five or more sugars are required to build a minimal epitope for TCR recognition. This suggests a mechanism for T cell recognition of glycosphingolipids in which much of the CD1b-bound ligand is exposed. Binding to CD1b is a highly reversible process and other ceramide-containing glycosphingolipids displace GM1. These nonantigenic compounds act as blockers and may prevent harmful autoreactivity in vivo.
T细胞识别脂多糖的结构基础仍有待阐明。我们已经描述了对由CD1b呈递的GM1神经节苷脂产生反应的自身反应性T细胞。我们发现糖鞘脂在中性pH条件下结合到细胞表面的CD1b上，且无需内化或加工即可被识别。此外，可溶性GM - CD1b复合物可刺激特异性T细胞。构建TCR识别的最小表位需要含有五个或更多糖的寡糖基团。这提示了一种T细胞识别糖鞘脂的机制，其中大部分与CD1b结合的配体是暴露的。与CD1b的结合是一个高度可逆的过程，其他含神经酰胺的糖鞘脂可取代GM1。这些非抗原性化合物起阻滞剂的作用，可能在体内防止有害的自身反应性。
