Porcelli S, Morita C T, Brenner M B
Department of Rheumatology/Immunology, Brigham and Women's Hospital, Boston, Massachusetts.
Nature. 1992 Dec 10;360(6404):593-7. doi: 10.1038/360593a0.
Molecules encoded by the human CD1 locus on chromosome 1 (ref. 33) are recognized by selected CD4-8- T-cell clones expressing either alpha beta or gamma delta T-cell antigen receptors. The known structural resemblance of CD1 molecules to antigen-presenting molecules encoded by major histocompatibility complex (MHC) genes on human chromosome 6 (refs 3, 4, 34, 35), suggested that CD1 may represent a family of antigen-presenting molecules separate from those encoded in the MHC. Here we report that the proliferative and cytotoxic responses of human CD4-8- alpha beta TCR+ T cells specific for Mycobacterium tuberculosis can be restricted by CD1b, one of the four identified protein products of the CD1 locus. The responses of these T cells to M. tuberculosis seemed not to involve MHC encoded molecules, but were absolutely dependent on the expression of CD1b by the antigen-presenting cell and involved an antigen processing requirement similar to that seen in MHC class II-restricted antigen presentation. These results provide, to our knowledge, the first direct evidence for the proposed antigen-presenting function of CD1 molecules and suggest that the CD1 family plays a role in cell-mediated immunity to microbial pathogens.
位于1号染色体上的人类CD1基因座所编码的分子，可被表达αβ或γδ T细胞抗原受体的特定CD4 - 8 - T细胞克隆识别。已知CD1分子与人类6号染色体上主要组织相容性复合体（MHC）基因所编码的抗原呈递分子在结构上存在相似性，这表明CD1可能代表了一类与MHC所编码分子不同的抗原呈递分子家族。在此我们报告，对结核分枝杆菌特异的人类CD4 - 8 - αβ TCR + T细胞的增殖和细胞毒性反应可受到CD1b的限制，CD1b是CD1基因座所鉴定出的四种蛋白质产物之一。这些T细胞对结核分枝杆菌的反应似乎不涉及MHC编码的分子，但绝对依赖于抗原呈递细胞表达CD1b，并且涉及一种类似于MHC II类限制的抗原呈递中所见的抗原加工需求。据我们所知，这些结果为CD1分子所提议的抗原呈递功能提供了首个直接证据，并表明CD1家族在针对微生物病原体的细胞介导免疫中发挥作用。
