Meyaard L, Hurenkamp J, Clevers H, Lanier L L, Phillips J H
Department of Immunobiology, DNAX Research Institute of Molecular and Cellular Biology, Palo Alto, CA 94304, USA.
J Immunol. 1999 May 15;162(10):5800-4.
Leukocyte associated Ig-like receptor-1 (LAIR-1) is a surface molecule expressed on human mononuclear leukocytes that functions as an inhibitory receptor on human NK cells. In addition to NK cells, LAIR-1 is expressed on T cells, B cells, macrophages, and dendritic cells. Most cells express two biochemically distinct forms of LAIR-1, which we now show are likely alternative splice variants of the same gene. Cross-linking of LAIR-1 on human T cell clones results in inhibition of cytotoxicity only in T cell clones that lack CD28 and are able to spontaneously lyse certain targets in vitro. Moreover, the cytolytic activity of freshly isolated T cells, which is thought to be mainly due to "effector" T cells, can be inhibited by anti-LAIR-1 mAb. Thus, LAIR-1 functions as an inhibitory receptor not only on NK cells, but also on human T cells. This indicates that LAIR-1 provides a mechanism of regulation of effector T cells and may play a role in the inhibition of unwanted bystander responses mediated by Ag-specific T cells.
白细胞相关免疫球蛋白样受体-1（LAIR-1）是一种在人类单核白细胞上表达的表面分子，它在人类自然杀伤细胞（NK细胞）上作为抑制性受体发挥作用。除了NK细胞外，LAIR-1还在T细胞、B细胞、巨噬细胞和树突状细胞上表达。大多数细胞表达两种生化特性不同的LAIR-1形式，我们现在证明它们可能是同一基因的可变剪接变体。在人类T细胞克隆上交联LAIR-1仅在缺乏CD28且能够在体外自发裂解某些靶标的T细胞克隆中导致细胞毒性抑制。此外，新鲜分离的T细胞的细胞溶解活性（被认为主要归因于“效应”T细胞）可被抗LAIR-1单克隆抗体抑制。因此，LAIR-1不仅在NK细胞上，而且在人类T细胞上都作为抑制性受体发挥作用。这表明LAIR-1提供了一种调节效应T细胞的机制，并且可能在抑制由抗原特异性T细胞介导的不必要的旁观者反应中发挥作用。
