title: The role of IL-4 in proliferation and differentiation of human natural killer cells. Study of an IL-4-dependent versus an IL-2-dependent natural killer cell clone.
abstract: The role of IL-4 in proliferation and differentiation of human NK cells was studied using newly established sublines of an IL-4-dependent NK cell clone (IL4d-NK cells) and an IL-2-dependent NK cell clone (IL2d-NK cells) derived from a parental conditioned medium-dependent NK cell clone (CM-NK cells). IL-4 induced the higher proliferation of CM-NK cells, but abolished their NK activity and decreased CD16 and CD56 Ag expression. In contrast, IL-2 induced the higher NK activity and increased CD16 and CD56 Ag expression. Addition of anti-IL-4 antibody to the culture of CM-NK cells with CM inhibited the proliferation, but slightly increased NK activity, and largely increased CD56 Ag expression. Addition of anti-IL-2 antibody to the culture of CM-NK cells with CM inhibited both proliferation and cytotoxicity. Proliferation of IL4d-NK cells, which is totally dependent on rIL-4, is greater than that of IL2d-NK cells, which was greater than parental CM-NK cells. Morphologically, IL4d-NK cells are small and round, whereas IL2d-NK cells are large and elongated. Anti-IL-4 antibody inhibited proliferation of IL4d-NK but not IL2d-NK cells, whereas anti-IL-2 antibody inhibited that of IL2d-NK but not IL4d-NK cells. IL-2 was not detected in the supernatant from IL4d-NK cells, nor was IL-2-mRNA expressed in IL4d-NK cells. In contrast, IFN-gamma production and protein expression in IL4d- and IL2d-NK cells were detected. NK cell activation markers (CD16 and CD56) were expressed on IL2d-NK cells but not IL4d-NK cells. IL4d-NK cells were not cytotoxic to any tumor cells tested, whereas IL2d-NK cells displayed potent NK activity and lymphokine-activated killer activity. IL4d-NK cells failed to bind K562 tumor cells, whereas one-third of the IL2d-NK cells did. IL4d-NK cells responded to rIL-2, proliferated, and differentiated into cytotoxic NK cells, whereas IL2d-NK cells failed to respond to rIL-4 and died. These results raise a possibility that IL4d-NK cells or IL2d-NK cells primarily represent the immunologic properties of immature or activated types of human NK cells, respectively. Our results provide the first evidence of the capability of IL-4 to support continuous proliferation of a lymphocyte clone with immature NK cell characteristics and to stimulate IFN-gamma production in the clone. IL-4 is suggested as a potential growth factor for certain types of human NK cell progenitors.
authors.affiliation: Department of Immunology, University of Texas M. D. Anderson Cancer Center, Houston 77030.
authors.forename: K
authors.initials: K
authors.lastname: Hayakawa
authors.forename: M A
authors.initials: MA
authors.lastname: Salmeron
authors.forename: J
authors.initials: J
authors.lastname: Kornbluth
authors.forename: C
authors.initials: C
authors.lastname: Bucana
authors.forename: K
authors.initials: K
authors.lastname: Itoh
mesh_terms: D015703:Antigens, CD / Q000378:metabolism; D002454:Cell Differentiation; D002455:Cell Division; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000502:physiology*; D015847:Interleukin-4 / Q000502:physiology*; D007694:Killer Cells, Natural / Q000166:cytology* / Q000276:immunology; D008213:Lymphocyte Activation; D008855:Microscopy, Electron, Scanning; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D011994:Recombinant Proteins; D013997:Time Factors
chemical_list: D015703:Antigens, CD; D006684:HLA-DR Antigens; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell; D011994:Recombinant Proteins; D015847:Interleukin-4; D007371:Interferon-gamma