%0 Journal Article %T Blocking immunoinhibitory receptor LILRB2 reprograms tumor-associated myeloid cells and promotes antitumor immunity %A Bin Zhang %A Dayanira Alsina-Beauchamp %A Hisashi Arase %A Hong-Ming Hu %A Hui-Ming Chen %A James A. Duty %A Jilu Zhang %A Kyeongah Kang %A Ping-Ying Pan %A Raja Flores %A Richard Flavell %A Sathish Kumar Mungamuri %A Shu-Hsia Chen %A Stuart Aaronson %A Sunny Mai %A Suresh Ramanathan %A Thomas Moran %A William van der Touw %A Yuan Shuo Wang %J The Journal of Clinical Investigation %D 2018 %R 10.1172/JCI97570 %X Tumor-associated myeloid cells maintain immunosuppressive microenvironments within tumors. Identification of myeloid-specific receptors to modulate tumor-associated macrophage and myeloid-derived suppressor cell (MDSC) functions remains challenging. The leukocyte immunoglobulin-like receptor B (LILRB) family members are negative regulators of myeloid cell activation. We investigated how LILRB targeting could modulate tumor-associated myeloid cell function. LILRB2 antagonism inhibited receptor-mediated activation of SHP1/2 and enhanced proinflammatory responses. LILRB2 antagonism also inhibited AKT and STAT6 activation in the presence of M-CSF and IL-4. Transcriptome analysis revealed that LILRB2 antagonism altered genes involved in cell cytoskeleton remodeling, lipid/cholesterol metabolism, and endosomal sorting pathways, as well as changed differentiation gene networks associated with inflammatory myeloid cells as opposed to their alternatively activated phenotype. LILRB2 blockade effectively suppressed granulocytic MDSC and Treg infiltration and significantly promoted in vivo antitumor effects of T cell immune checkpoint inhibitors. Furthermore, LILRB2 blockade polarized tumor-infiltrating myeloid cells from non¨Csmall cell lung carcinoma tumor tissues toward an inflammatory phenotype. Our studies suggest that LILRB2 can potentially act as a myeloid immune checkpoint by reprogramming tumor-associated myeloid cells and provoking antitumor immunity %U https://www.jci.org/articles/view/97570