Abstract 60: In Vitro Assay Platform to Test Anti-CD47 Agents

CD47 expression predicts efficacy of macrophage-mediated phagocytosis of tumor cells

Huajun Yang, Zhongliang Li, Beibei Tang, Zegen Wang, Phillip Wang, Qinyun Ma*, Frank Xing, and Qian Shi

*Huashan Hospital Affiliated to Fudan University, Shanghai, China

CD47 is a transmembrane protein belonging to the immunoglobulin family. It acts as a “don’t eat me” signal, inhibiting cell clearance by macrophages. By blocking CD47 with antibodies it is possible to restore this macrophage phagocytic activity, making CD47 an interesting target in immuno-oncology research.

CrownBio has developed a robust and reproducible in vitro assay platform to assess the antitumor phagocytic activity of macrophages that have been exposed to tumor cells and to evaluate novel therapeutic agents targeting CD47.

This poster details the assay scheme, in vitro findings, and initial in vivo validation data generated via paired isogenic cell models overexpressing CD47 or with the gene knocked out.

Read this Poster to Discover:

• That disrupting the CD47-SIRPa anti-phagocytic axis is a novel immunotherapy approach against cancer
• That while M1 and M2 macrophages demonstrate comparable anti-CD47 antibody specific phagocytic activity, anti-CD274 (PD-L1) treatment only yields phagocytic activity comparable with isotype controls
• Among anti-CD47 antibodies, BRIC126 confers the most robust phagocytic activity in two model systems, M2/Karpas299 and M2/SK-OV-3, while the non-blocking 2D3 clone is a negative control

Download the Poster Now!