LEUCOKYTE COMMON ANTIGEN (CD45) IS INVOLVED IN NEUTROPHIL CHEMOTAXIS

CD 45抗原家族是一组高分子量糖蛋白 在所有白细胞的质膜上表达。CD 45有 蛋白酪氨酸磷酸酶活性，并似乎调节信号 通过特异性结合转导和淋巴细胞活化 T和B淋巴细胞上的受体分子。然而，人们对 中性粒细胞（PMN）中的CD 45功能。在这项研究中， 用CD 45单克隆抗体（mAb），并测试其趋化性 对四种不相关的化学引诱物的反应：N-甲酰基-甲硫氨酰基 - 亮氨酰-苯丙氨酸（FMLP）、白三烯B4（LTB 4）、重组人C5 a (C5a)和重组人中性粒细胞活化蛋白-1（NAP-1）， 最近被命名为白细胞介素8（IL 8）。一组CD 45单克隆抗体，包括 一种IgM mAb，AHN-12.1，和六种IgGl mAb，AHN-12，AHN-12.2，AHN-12.3， 检测AHN-12.4、HLe-1和KC 56（T200）对PMN的作用 趋化性用两种不同的细胞膜评价PMN的趋化性 测定：一种测定the.total了迁移的PMN的数量， 另一组检测PMNS迁移前沿。AHN-12.1和KC 56（T200） 显着抑制中性粒细胞对LTB 4和C5 a的趋化性。AHN-12.1还 KC 56（T200）抑制PMN对FMLP的趋化作用，而KC 56（T200）无此作用。与此相反， AHN-12和HLe-1并不显著抑制PMN对任何一种细胞的趋化性。 化学引诱物CD 45单克隆抗体均不能抑制PMN对NAP-1的趋化性。 IL 8。这些结果表明PMN CD 45表位可能与LTB 4相互作用， C5 a和FMLP受体或受体相关分子，并调节 趋化反应 这项研究的结果在美国社会上发表， 生物化学和美国免疫学家协会联合 会议，1990年6月3日至7日，新奥尔良，洛杉矶。

The CD45 antigen family is a group of high molecular weight glycoproteins that are expressed on the plasma membranes of all leukocytes. CD45 has protein tyrosine phosphatase activity and appears to regulate signal transduction and lymphocyte activation by specific association with receptor molecules on T and B lymphocytes. However, little is known about CD45 function in neutrophils (PMNs). In this study, PMNs were incubated with CD45 monoclonal antibodies (mAbs) and tested for their chemotactic responses to four unrelated chemoattractants: N-formyl-methionyl -leucyl-phenylalanine (FMLP), leukotriene B4 (LTB4), recombinant human C5a (C5a), and recombinant human neutrophil activating protein-1 (NAP-1), recently designated as interleukin 8 (IL8). A panel of CD45 mabs including an IgM mAb, AHN-12.1, and six IgGl mAbs, AHN-12, AHN-12.2, AHN-12.3, AHN-12.4, HLe-1, and KC56(T200), were tested for their effects on PMN chemotaxis. PMN chemotaxis.was evaluated with two different membrane assays: one assay quantified the.total number of migrating PMNs and the other assayed the leading front of migrating PMNS. AHN-12.1 and KC56(T200) significantly inhibited PMN chemotaxis to LTB4 and C5a. AHN-12.1 also inhibited PMN chemotaxis to FMLP, but KC56(T200) did not. In contrast, AHN-12 and HLe-1 did not significantly inhibit PMN chemotaxis to any of the chemoattractants. None of the CD45 mAbs inhibited PMN chemotaxis to NAP-1/ IL8. These results indicate that PMN CD45 epitopes may interact with LTB4, C5a, and FMLP receptors or receptor-associated molecules and regulate chemotactic responses. The results of this study were presented at the American Society for Biological Chemistry and the American Association of Immunologists Joint Meeting, June 3-7, 1990, New Orleans, LA.