Recognition of CHO cells by inhibitory and activating Ly-49 receptors.
Upon ligand recognition, members of the murine Ly-49 receptor family can transmit inhibitory or activating signals that regulate NK cell function. Ly-49A, G, and D have been shown to recognize the murine class I molecule H-2Dd as a potential ligand. Recent studies also have demonstrated also that Ly-49D+ NK cells can lyse CHO cells, although the ligand responsible for this recognition was not identified. Because allorecognition by NK cells may be important in bone-marrow transplantation and because of the overlapping class I recognition by these receptors, recognition of CHO cells by Ly-49G and A was investigated. Our data suggest that Ly-49G and probably A transmit inhibitory signals in response to CHO cells. Receptor inhibition was assessed by examining NK lytic function, IFN-gamma secretion, and DAP12 phosphorylation in response to CHO cells by sorted subsets of Ly-49D vs. G B6 NK cells. Our results suggest that CHO cells may express a common ligand(s) that is capable of engaging Ly-49D, G, and possibly A in C576BL/6 NK cells. In addition to our findings that Ly-49 inhibitory receptors also recognize CHO cells, activating receptors other than Ly-49D are present in B6 mice that can lyse CHO cells.
Mason
L H
LH
Laboratory of Experimental Immunology, Division of Basic Sciences, National Cancer Institute-FCRDC, Frederick, Maryland 21702-1201, USA. masonl@mail.ncifcrf.gov
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology; D000950:Antigens, Ly; D016466:CHO Cells / Q000276:immunology*; D006224:Cricetinae; D003412:Cricetulus / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D006183:H-2 Antigens / Q000276:immunology*; D064532:Histocompatibility Antigen H-2D; D007371:Interferon-gamma / Q000378:metabolism; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D037181:Lectins, C-Type; D016131:Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000276:immunology / Q000502:physiology*; D008565:Membrane Proteins; D051379:Mice; D008810:Mice, Inbred C57BL / Q000276:immunology*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D011971:Receptors, Immunologic / Q000378:metabolism; D055630:Receptors, NK Cell Lectin-Like; D013045:Species Specificity
D048868:Adaptor Proteins, Signal Transducing; D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D011971:Receptors, Immunologic; D055630:Receptors, NK Cell Lectin-Like; C110546:TYROBP protein, human; D007371:Interferon-gamma