Poster Presentation Asia-Pacific Vaccine and Immunotherapy Congress 2024

Chimeric Antigen Receptor Monocytes With Enhanced Anti-Tumor Activities By Harnessing Innate Immunity Pathways (#123)

Neha Diwanji 1 , Tyler Nicholson 1 , Thomas Prod'homme 1 , Bruce McCreedy 1 , Yuxiao Wang 1 , Daniel Getts 1
  1. Myeloid Therapeutics, Cambridge, MASSACHUSETTS, United States

Myeloid cells, including monocytes and macrophages are the primary orchestrators of immune responses and are found to accumulate abundantly in solid tumors. These cells express a wide range of innate immune sensors such as Toll-like receptors (TLRs), RIG-I and cGAS-STING. The activation of these innate immune pathways can remodel tumor microenvironment and initiate broad immune responses against tumor. Here we designed a new class of chimeric antigen receptors for monocytes that couple tumor recognition with multiple innate immune signaling domains. We screened a broad range of innate immunity signaling molecules and optimized a CAR that incorporates a domain of the TLR adaptor molecule TRIF. The TRIF-CAR targeting human HER2 upregulated the pro-inflammatory cytokines and chemokines including IP10, CCL5 and IFNalpha and enhanced tumor killing activity. Transcriptome-wide analysis revealed that the addition of TRIF to the CAR broadly upregulated genes associated with a pro-inflammatory response, T-cell co-stimulation as well as myeloid cell migration and trafficking. Immunosuppressive molecules such as TREM2 were downregulated. Our data show that the incorporation of a TRIF domain into a myeloid-specific CAR can enhance the innate anti-tumor activity of myeloid cells.