Gosselin P, Lusignan Y, Lemieux S
Centre de Recherche en Immunologie, Institut Armand-Frappier, Université du Québec, Laval, Canada.
Mol Immunol. 1993 Sep;30(13):1185-93. doi: 10.1016/0161-5890(93)90137-z.
Murine natural killer (NK) cells express a few antigens not found on other leukocyte subsets. The NK1.1 antigen, that is present in only a few mouse strains, has been extensively characterized whereas our knowledge of the NK2.1 antigen, which is more commonly expressed, remains, as yet, limited. Our laboratory has previously reported the production of a mAb (4LO3311) recognizing a murine NK cell-specific molecule with a similar strain distribution as the NK2.1 antigen formerly defined with an NZB anti-BALB/c antiserum. In this study, we demonstrate by sequential immunoprecipitation that 4LO3311 represents the first NK2.1 antigen-specific mAb. This reagent was used to immunoprecipitate the NK2.1 antigen from 125I-labeled lysates of fresh NK-enriched spleen cells. SDS-PAGE analyses revealed that the NK2.1 antigen is expressed at the cell surface as a N-glycosylated disulfide-linked protein dimer with approximately 65 kD subunits. The NK2.1 antigen is likely to be anchored in the plasma membrane by a peptide moiety since its expression on NK cells was not affected by treatment with phosphatidylinositol-specific phospholipase C. In addition to be present on a splenic NK cell subset, the NK2.1 antigen is shown to be expressed by a small number of CD4-CD8-thymocytes and by a subset of CD4-CD8-IgG- lymph node cells. Finally, it is shown here that unlike the NKR-P1, the rat homologue of the murine NK1.1 antigen, neither the NK2.1 nor the NK1.1 antigen is expressed by polymorphonuclear leukocytes.
小鼠自然杀伤（NK）细胞表达一些在其他白细胞亚群中未发现的抗原。仅在少数小鼠品系中存在的NK1.1抗原已得到广泛表征，而我们对更普遍表达的NK2.1抗原的了解仍然有限。我们实验室先前报道了一种单克隆抗体（4LO3311）的产生，该抗体识别一种小鼠NK细胞特异性分子，其品系分布与先前用NZB抗BALB/c抗血清定义的NK2.1抗原相似。在本研究中，我们通过连续免疫沉淀证明4LO3311代表第一种NK2.1抗原特异性单克隆抗体。该试剂用于从新鲜NK富集脾细胞的125I标记裂解物中免疫沉淀NK2.1抗原。SDS-PAGE分析显示，NK2.1抗原在细胞表面表达为一种N-糖基化的二硫键连接的蛋白质二聚体，亚基约为65 kD。NK2.1抗原可能通过肽部分锚定在质膜中，因为其在NK细胞上的表达不受磷脂酰肌醇特异性磷脂酶C处理的影响。除了存在于脾脏NK细胞亚群上，NK2.1抗原还显示在少数CD4-CD8-胸腺细胞和CD4-CD8-IgG-淋巴结细胞亚群中表达。最后，这里表明，与小鼠NK1.1抗原的大鼠同源物NKR-P1不同，多形核白细胞既不表达NK2.1抗原也不表达NK1.1抗原。
