title: Preferential proliferation of natural killer cells among peripheral blood mononuclear cells cocultured with B lymphoblastoid cell lines.
abstract: In this report, we show that in vitro stimulation of human peripheral blood mononuclear cells (PBMC) with B lymphoblastoid cell lines results in preferential proliferation of cells with the phenotypic, genotypic and functional characteristics of natural killer (NK) cells. This culture system offers a useful method for obtaining large numbers of pure NK cells on which biochemical, molecular and functional studies can be performed. Using this culture system, and average 25-fold increase in NK cell number is obtained, whereas the number of T cells is increased only 3-fold. At early times, activation of both T and NK cells occurs, as detected by the presence of activation antigens on both cell types, but actual proliferation of NK cells starts on day 6 of culture. Elimination of CD3(+)/CD5(+) T cells from the cultured cells gives homogeneous preparations of large numbers of CD16(+)/NKH-1(+) cells that have the morphology of large granular lymphocytes, are powerful effectors of both spontaneous and antibody-dependent cell-mediated cytotoxicity, and rapidly proliferate in the presence of recombinant interleukin 2 (rIL-2). As fresh NK cells, NK cell-enriched preparations from 10-day cultures of Daudi-stimulated PBMC do not show rearrangement of the gene for the beta-chain of the T cell antigen receptor; the 1.3-kb functional transcript of the beta-chain gene was not expressed in NK cells, but the 1.0-kb truncated transcript was present in all preparations. Our data indicate that proliferation of both T and NK cells is dependent upon IL-2 production in the culture, because an anti-IL-2 antiserum completely suppresses proliferation. Because T cells, and in particular CD4(+) T cells, are required for preferential proliferation of NK cells, the NK cell stimulation induced by the B cell line is probably in part indirect, and due to induction of IL-2 production by allogeneic stimulation of CD4(+) cells. However, the B cell lines also need to interact directly with NK cells because neither allogeneic PBMC nor high doses of rIL-2 are sufficient to induce preferential proliferation of NK cells.
mesh_terms: D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation / Q000032:analysis; D001402:B-Lymphocytes / Q000166:cytology*; D002455:Cell Division; D002460:Cell Line; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D005796:Genes; D006801:Humans; D007111:Immunity, Cellular; D007113:Immunity, Innate; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000166:cytology* / Q000276:immunology / Q000648:ultrastructure; D007963:Leukocytes, Mononuclear / Q000166:cytology*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D016693:Receptors, Antigen, T-Cell, alpha-beta; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology
chemical_list: D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta