Triggering of natural killer cells by the costimulatory molecule CD80 (B7-1)

Immunity. 1996 Oct;5(4):311-7. doi: 10.1016/s1074-7613(00)80257-5.


NK cell-mediated cytotoxicity is influenced by triggering as well as inhibitory signals. The identification of inhibitory signals provided by MHC class I molecules has recently attracted significant attention. Much less is known about putative triggering signals. Using purified populations of mouse NK cells, we demonstrate that the CD80 (B7-1) gene product functions as a triggering signal for NK cell-mediated cytotoxicity. The strength of this response is such that it overrides the protection mediated by MHC class I molecules. Triggering of mouse NK cells by B7-1 occurred even in the absence of CD28 and could not be blocked by either anti-CD28 or anti-CTLA-4 antibodies. NK cells may thus, at least in part, use receptors other than CD28 and CTLA-4 in their interaction with B7-1. Furthermore, we demonstrate that bone marrow-derived macrophages and dendritic cells are highly susceptible to lysis by autologous NK cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • B7-1 Antigen / immunology*
  • Bone Marrow Cells
  • Cytotoxicity, Immunologic*
  • Dendritic Cells / immunology
  • Histocompatibility Antigens Class I / immunology
  • Killer Cells, Natural / immunology*
  • Macrophages / immunology
  • Mice
  • Signal Transduction


  • B7-1 Antigen
  • Histocompatibility Antigens Class I