title: Mouse Ly49G2+ NK cells dominate early responses during both immune reconstitution and activation independently of MHC.
abstract: Natural killer (NK) cell subsets can be defined by the differential expression of inhibitory receptors for MHC class I molecules. Early after congenic HSCT, we found that Ly49G2(high) single-positive NK cells repopulated, displayed an activated phenotype, and were highly cytolytic. Over time, this subset was replaced with NK cells with a normal pattern of Ly49 expression. Treatment of mice with IL-2 also resulted in the rapid expansion of these Ly49G2(high) single-positive NK cells. Only the Ly49g (Klra7) Pro1 transcript was highly induced in both HSCT- and IL-2-treated recipients. MHC-independent expansion of the Ly49G2(+) subset was also observed after Listeria monocytogenes or mouse cytomegalovirus infection. Our data indicate that during reconstitution after HSCT and various activation stimuli, Ly49G2(+) NK cells represent the "first-responder" NK cells, which occur independently of NK-cell licensing via Ly49-MHC interactions. These data suggest that the inhibitory Ly49G2 receptor represents an activation marker on mouse NK cells under various conditions.
authors.affiliation: Department of Microbiology and Immunology, University of Nevada, Reno, Reno, NV, USA.
authors.forename: Isabel
authors.initials: I
authors.lastname: Barao
authors.forename: Maite
authors.initials: M
authors.lastname: Alvarez
authors.forename: Erik
authors.initials: E
authors.lastname: Ames
authors.forename: Mark T
authors.initials: MT
authors.lastname: Orr
authors.forename: Heather E
authors.initials: HE
authors.lastname: Stefanski
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Blazar
authors.forename: Lewis L
authors.initials: LL
authors.lastname: Lanier
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Anderson
authors.forename: Doug
authors.initials: D
authors.lastname: Redelman
authors.forename: William J
authors.initials: WJ
authors.lastname: Murphy
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D003587:Cytomegalovirus / Q000276:immunology; D005260:Female; D005786:Gene Expression Regulation; D006085:Graft Survival; D018380:Hematopoietic Stem Cell Transplantation; D007376:Interleukin-2 / Q000378:metabolism; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D008089:Listeria monocytogenes / Q000276:immunology; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex; D051379:Mice; D020297:Mice, Congenic; D008815:Mice, Inbred Strains; D009369:Neoplasms / Q000276:immunology; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D015415:Biomarkers; C508594:IL2 protein, human; D007376:Interleukin-2; C452844:Ly49G2 receptor; D011971:Receptors, Immunologic; D011994:Recombinant Proteins