| First Author | Nakayama M | Year | 2011 |
| Journal | Proc Natl Acad Sci U S A | Volume | 108 |
| Issue | 45 | Pages | 18360-5 |
| PubMed ID | 22042851 | Mgi Jnum | J:180232 |
| Mgi Id | MGI:5305883 | Doi | 10.1073/pnas.1110584108 |
| Citation | Nakayama M, et al. (2011) Natural killer (NK)-dendritic cell interactions generate MHC class II-dressed NK cells that regulate CD4+ T cells. Proc Natl Acad Sci U S A 108(45):18360-5 |
| abstractText | Natural killer (NK) cells contribute to not only innate but also to adaptive immunity by interacting with dendritic cells (DCs) and T cells. All activated human NK cells express HLA-DR and can initiate MHCII-dependent CD4(+) T-cell proliferation; however, the expression of MHCII by mouse NK cells and its functional significance are controversial. In this study, we show that NK-DC interactions result in the emergence of MHCII-positive NK cells. Upon in vitro or in vivo activation, mouse conventional NK cells did not induce MHCII transcripts, but rapidly acquired MHCII protein from DCs. MHCII H2-Ab1-deficient NK cells turned I-A(b)-positive when adoptively transferred into wild-type mice or when cultured with WT splenic DCs. NK acquisition of MHCII was mediated by intercellular membrane transfer called "trogocytosis," but not upon DAP10/12- and MHCI-binding NK cell receptor signaling. MHCII-dressed NK cells concurrently acquired costimulatory molecules such as CD80 and CD86 from DCs; however, their expression did not reach functional levels. Therefore, MHCII-dressed NK cells inhibited DC-induced CD4(+) T-cell responses rather than activated CD4(+) T cells by competitive antigen presentation. In a mouse model for delayed-type hypersensitivity, adoptive transfer of MHCII-dressed NK cells attenuated footpad swelling. These results suggest that MHCII-dressed NK cells generated through NK-DC interactions regulate T cell-mediated immune responses. |
