Interleukin 2 enhances natural killing of normal lymphocytes.
Purified Interleukin 2 (IL-2), free of interferon (IFN), significantly enhanced NK activity of normal human peripheral blood mononuclear cells (PBMC). This enhancing activity was absorbed by IL-2 receptor-bearing cells but was not blocked by antibody to alpha-IFN. IFN in the culture supernatants was greatly increased after stimulation with poly(I:C) plus IL-2. There was less IFN produced by either modulator acting alone. Stimulation of PBMC with IL-2 and/or poly(I:C) increased the proportion of OKM1+ cells and anti-Leu-7+ cells. When cells expressing either surface antigen were specifically lysed to deplete NK, cytotoxic activity could be restored by overnight incubation in IL-2. This result suggests that IL-2 stimulates the development of NK cells from precursors that lack cell surface OKM1 or Leu-7. IL-2 acted directly on large granular lymphocytes and did not require the presence of adherent cells. These results suggest that IL-2 may act synergistically with other IFN inducers and may play an important role in the regulation of NK cells.
D000042:Absorption; D000911:Antibodies, Monoclonal / Q000502:physiology; D000914:Antibodies, Viral / Q000502:physiology; D001667:Binding, Competitive; D002448:Cell Adhesion; D003165:Complement System Proteins / Q000502:physiology; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007370:Interferon Type I / Q000276:immunology; D007376:Interleukin-2 / Q000378:metabolism / Q000502:physiology*; D007694:Killer Cells, Natural / Q000276:immunology*; D007700:Kinetics; D008213:Lymphocyte Activation; D011070:Poly I-C / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D007370:Interferon Type I; D007376:Interleukin-2; D003165:Complement System Proteins; D011070:Poly I-C