Tyrosine kinase-dependent activation of human NK cell functions upon stimulation through a 58-kDa surface antigen selectively expressed on discrete subsets of NK cells and T lymphocytes.

摘要: We have raised a mAb, termed HP-3E4 (IgM), by immunizing BALB/c mice against human IL2-activated NK cells. The mAb recognized in different donors variable proportions (< 2-70%) of either fresh or activated A small population T cells (alpha/beta and gamma/delta) appeared HP-3E4+ PBL. No reactivity was detected on other leukocytes panel cell lines from lineages. By immunohistochemical staining tissues, few were only lymphoid organs. Analysis CD56+CD16+CD3- clones (n = 167) unrelated 6), showed that the Ag stably expressed 8 to 70%, moreover it some gamma/delta + clones, whereas all CD3+ alpha/beta +(CD4+ CD8+) analyzed 90) HP-3E4-. As assessed SDS-PAGE analysis, immunoprecipitated 58-kDa surface structure. When compared with two mAbs (GL183 EB6) previously reported bind also clonally distributed 54- Ag, recognize distinct epitope, thus allowing further define subsets. Stimulation triggered TNF-alpha IFN-gamma production, which enhanced using attached plastic presence suboptimal concentrations phorbol esters. Although did not significantly modify cell-mediated cytotoxicity targets, exception Hmy-C1R line, BLT esterase secretion. Remarkably, phosphoinositide turnover an early increase [Ca2+]i, as well tyrosine phosphorylation several cellular substrates including CD3 zeta; inhibition kinase activity genistein hampered HP-3E4-mediated stimulation cytokine production. Our data provide support for structural diversity whose expression is restricted discrete Moreover, results fact molecule plays active role regulating functions through signal transduction mechanisms comparable those via Fc gamma RIII.