TY - JOUR A1 - Koch, Christine A1 - Kim, Younghoon A1 - Zöller, Tobias A1 - Born, Christina A1 - Steinle, Alexander T1 - Chronic NKG2D engagement in vivo differentially impacts NK cell responsiveness by activating NK receptors T2 - Frontiers in immunology N2 - Immunosuppression is a typical hallmark of cancer and frequently includes perturbations of the NKG2D tumor recognition system as well as impaired signaling by other activating NK cell receptors. Several in vitro studies suggested that sustained engagement of the NKG2D receptor, as it is occurring in the tumor microenvironment, not only impairs expression and function of NKG2D but also impacts signaling by other activating NK receptors. Here, we made use of a transgenic mouse model of ubiquitous NKG2D ligand expression (H2-Kb-MICA mice) to investigate consequences of chronic NKG2D engagement in vivo for functional responsiveness by other activating NK receptors such as NKp46 and Ly49D. Unexpectedly, we found no evidence for an impairment of NKp46 expression and function in H2-Kb-MICA mice, as anticipated from previous in vitro experiments. However, we observed a marked downregulation and dysfunction of the activating receptor Ly49D in activated NK cells from H2-Kb-MICA mice. Ly49D shares the adaptor proteins DAP10 and DAP12 with NKG2D possibly explaining the collateral impairment of Ly49D function in situations of chronic NKG2D engagement. Altogether, our results demonstrate that persistent engagement of NKG2D in vivo, as often observed in tumors, can selectively impair functions of unrelated NK receptors and thereby compromise NK responsiveness to third-party antigens. KW - NKG2D KW - NK cells KW - MICA KW - signal transduction KW - NK receptors Y1 - 2017 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/46356 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-463566 SN - 1664-3224 N1 - Copyright: © 2017 Koch, Kim, Zöller, Born and Steinle. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. VL - 8 IS - Art. 1466 SP - 1 EP - 11 PB - Frontiers Media CY - Lausanne ER -