Porcelli S, Brenner M B, Greenstein J L, Balk S P, Terhorst C, Bleicher P A
Department of Rheumatology and Immunology, Brigham and Women's Hospital, Boston, Massachusetts.
Nature. 1989 Oct 5;341(6241):447-50. doi: 10.1038/341447a0.
Human cluster-of-differentiation 1 (CD1) is a family of cell surface glycoproteins of unknown function expressed on immature thymocytes, epidermal Langerhans cells and a subset of B lymphocytes. Three homologous proteins, CD1a, b and c, have been defined serologically, and the CD1 gene locus on human chromosome 1 contains five potential CD1 genes. Analysis of the predicted amino-acid sequences of CD1 molecules reveals a low but significant level of homology to major histocompatibility complex (MHC) class I and class II molecules, and, like MHC class I molecules, CD1 molecules are associated non-covalently with beta 2-microglobulin. These structural similarities to known antigen-presenting molecules, together with the expression of CD1 on cells capable of antigen presentation, suggest a role for CD1 molecules in antigen recognition by T cells. Here we demonstrate the specific recognition of CD1a by a CD4-CD8- alpha beta T-cell receptor (TCR) expressing cytolytic T lymphocyte (CTL) line and the specific recognition of CD1c by a CD4-CD8- gamma delta TCR CTL line. The interaction of CD1-specific CTLs with CD1+ target cells appeared to involve the CD3-TCR complex, and did not show evidence of MHC restriction. These results suggest that for a subset of T cells, CD1 molecules serve a function analogous to that of MHC class I and II molecules.
人类分化簇1（CD1）是一类细胞表面糖蛋白家族，其功能未知，在未成熟胸腺细胞、表皮朗格汉斯细胞和一部分B淋巴细胞上表达。通过血清学方法已确定了三种同源蛋白，即CD1a、b和c，并且人类1号染色体上的CD1基因座包含五个潜在的CD1基因。对CD1分子预测氨基酸序列的分析显示，其与主要组织相容性复合体（MHC）I类和II类分子存在低但显著水平的同源性，并且与MHC I类分子一样，CD1分子与β2-微球蛋白非共价结合。这些与已知抗原呈递分子的结构相似性，以及CD1在能够进行抗原呈递的细胞上的表达，表明CD1分子在T细胞识别抗原中发挥作用。在此我们证明了表达细胞毒性T淋巴细胞（CTL）系的CD4-CD8-αβT细胞受体（TCR）对CD1a的特异性识别以及CD4-CD8-γδTCR CTL系对CD1c的特异性识别。CD1特异性CTL与CD1+靶细胞的相互作用似乎涉及CD3-TCR复合体，并且未显示出MHC限制性的证据。这些结果表明，对于一部分T细胞而言，CD1分子发挥着与MHC I类和II类分子类似的功能。
