Rat Anti-Mouse CD70 Monoclonal antibody, clone FR70 Functional Grade

Diacylglycerol lipase-beta (DAGL beta) hydrolyzes arachidonic acid (AA)-esterified diacylglycerols to produce 2-arachidonoylglycerol (2-AG) and downstream prostanoids that mediate inflammatory responses of macrophages. Here, we utilized DAGL-tailored activity-based protein profiling and genetic disruption models to discover that DAGL beta regulates inflammatory lipid and protein signaling pathways in primary dendritic cells (DCs). DCs serve as an important link between innate and adaptive immune pathways by relaying innate signals and antigen to drive T cell clonal expansion and prime antigen-specific immunity. We discovered that disruption of DAGL beta in DCs lowers cellular 2-AG and AA that is accompanied by reductions in lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha secretion. Cell-based vaccination studies revealed that DC maturation ex vivo and immunogenicity in vivo was surprisingly unaffected by DAGL beta inactivation. Collectively, we identify DAGL beta pathways as a means for attenuating DC inflammatory signaling while sparing critical adaptive immune functions and further expand the utility of targeting lipid pathways for immunomodulation.

Purpose: PD-1 checkpoint blockade has revolutionized the field of cancer immunotherapy, yet the Frequency of responding patients is limited by inadequate T-cell priming secondary to a paucity of activatory dendritic cells (DC). DC signals can be bypassed by CD27 agonists, and we therefore investigated if the effectiveness of anti-PD-1/L1 could be improved by combining with agonist anti-CD27 monoclonal antibodies (mAb). Experimental Design: The efficacy of PD-1/L1 blockade or agonist anti-CD27 mAb was compared with a dual-therapy approach in multiple tumor models. Global transcriptional profiling and flow cytometry analysis were used to delineate mechanisms underpinning the observed synergy. Results: PD-1/PD-L1 blockade and agonist anti-CD27 mAb synergize for increased CD8(+) T-cell expansion and effector function, exemplified by enhanced IFN gamma, TNF alpha, granzyme beta, and T-bet. Transcriptome analysis of CD8(+) T cells revealed that combination therapy triggered a convergent program largely driven by 11.2 and Myc. However, division of labor was also apparent such brat anti-PD-1/1.1 activates a cytotoxicity-gene expression program whereas anti-CD27 preferentially augments proliferation. In tumor models, either dependent on endogenous CD8(+) T cells or adoptive transfer of transgenic T cells anti-CD27 mAb synergized with PD-1/L1 blockade for antitumor immunity. Finally, we show that a clinically relevant anti-human CD27 mAb, varlilwnab, similarly synergizes with PD-L1 blockade for protection against lymphoma in human-CD27 transgenic mice. Conclusions: Our findings suggest that suboptimal T-cell in vigoration in cancer patients undergoing treatment with PD-L1 checkpoint blockers will be improved by dual PD-L1 blockade and CD27 agonism and provide mechanistic insight into how these approaches cooperate for CD8(+) T-cell activation. (C) 2018 AACR.