TY - JOUR TI - LILRB4 suppresses immunity in solid tumors and is a potential target for immunotherapy AU - Sharma, Naveen AU - Atolagbe, Oluwatomisin T. AU - Ge, Zhongqi AU - Allison, James P. T2 - Journal of Experimental Medicine AB - Immune receptors expressed on TAMs are intriguing targets for tumor immunotherapy. In this study, we found inhibitory receptor LILRB4 on a variety of intratumoral immune cell types in murine tumor models and human cancers, most prominently on TAMs. LILRB4, known as gp49B in mice, is a LILRB family receptor. Human and murine LILRB4 have two extracellular domains but differ in the number of intracellular ITIMs (three versus two). We observed a high correlation in LILRB4 expression with other immune inhibitory receptors. After tumor challenge, LILRB4−/− mice and mice treated with anti-LILRB4 antibody showed reduced tumor burden and increased survival. LILRB4−/− genotype or LILRB4 blockade increased tumor immune infiltrates and the effector (Teff) to regulatory (Treg) T cell ratio and modulated phenotypes of TAMs toward less suppressive, CD4+ T cells to Th1 effector, and CD8+ T cells to less exhausted. These findings reveal that LILRB4 strongly suppresses tumor immunity in TME and that alleviating that suppression provides antitumor efficacy. DA - 2021/05/11/ PY - 2021 DO - 10.1084/jem.20201811 DP - Silverchair VL - 218 IS - e20201811 J2 - Journal of Experimental Medicine SN - 0022-1007 UR - https://doi.org/10.1084/jem.20201811 Y2 - 2021/05/14/23:48:42 ER -