gp75-CD89

gp75-CD89 is an mRNA-based therapeutic candidate developed by Myeloid Therapeutics. It consists of mRNA encapsulated in lipid nanoparticles (LNPs) that encodes a chimeric fusion receptor. This receptor combines a single-chain variable fragment (scFv) targeting the melanoma antigen gp75 (Tyrosinase-related protein 1) with the alpha chain of the human IgA receptor (CD89). Upon intravenous administration, the LNPs are taken up by myeloid cells, which then express the gp75-CD89 fusion protein on their surface. The receptor utilizes the endogenous common Fc receptor gamma chain (FcRγ) for signaling, effectively programming myeloid cells to recognize and eliminate gp75-expressing tumor cells. In preclinical syngeneic melanoma models, gp75-CD89 has demonstrated the ability to initiate broad systemic immune responses, including increased tumor infiltration by activated CD8+ T cells and reduced tumor-associated regulatory T cells (Tregs).