Researchers from Elpiscience Biopharma Ltd. have reported the construction of a PD-L1/SIRPα bispecific macrophage engager (BiME), ES-019. A panel of anti-PD-L1/SIRPα antibodies based on single domain antibody was generated, with the candidates containing different orientations, ratios and IgG isotypes of anti-PD-L1 arm and anti-SIRPα arm.