CD47 Antibody-Induced Engulfment of Human Leukaemic T-Cells by Bone-Marrow Derived Macrophages

CD47 is a cell-surface marker of self, or “don’t-eat-me” signal. Expression of CD47 enables tumour cells to evade clearance by host macrophages. Blocking CD47 holds great promise as a therapeutic strategy for both solid and hematologic cancers. This poster describes a validated, automated image-based 96-well assay for anti-CD47antibody-mediated cellular phagocytosis. Tumour cells were labelled with pHrodo, a pH-sensitive dye, and added to phagocytes (e.g. BMDMs). When the labelled cells were engulfed into the acidic lysosome; the change in pH caused the labelled cells to become fluorescent. This approach is amenable to many cell types and enables researchers to screen for small molecules or antibodies that enhance or inhibit phagocytosis.