HAB21 potently enhanced macrophage phagocytosis of DLD-1 tumor cells in a dose-dependent manner irrespective of SIRPα genotype with an EC50 of ~ 0.2 nM, consistent with the high affinity binding of hAB21 to both SIRPα v1 and v2 variants (Fig. 3a). Here, SIRPA is linked to neoplasm.