Cytotoxic effect on neoplastic B cells through macrophages expressing CD19-CAR with costimulatory domains of Dectin-1 or FcR.

• Grant number: 24/20125-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: May 01, 2025
• End date: July 31, 2026
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal Investigator: Thiago Aparecido da Silva
• Grantee: Victor Gabriel Santos Silva
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

B-cell neoplasms represent a significant portion of hematologic malignancies and are associated with therapeutic challenges due to the toxicity of conventional treatments and recurrence. CAR-T cell therapy is characterized by the use of chimeric antigen receptors (CAR) with the ability to redirect the cytotoxic activity of modified T cells in a target-specific manner, as demonstrated by the progress made with CD19-CAR in the treatment of B-cell neoplasms. Cellular therapy with CAR technology has shown promise in utilizing different immune cells to control B-cell neoplasms in an attempt to mitigate cytokine release syndrome and neurotoxicity caused by CD19-CAR T cell therapy. In this context, previous studies have shown that expressing CD19-CAR in macrophages and/or monocytes favors tumor progression control with reduced side effects. The present proposal aims to modify macrophages with CD19-CAR containing different intracellular signaling transduction domains, involving Dectin-1, Fc¿R¿1, or Fc¿R1 as costimulatory molecules. Incorporating the signaling domain of Dectin-1, Fc¿R¿1, or Fc¿R1 into the creation of CD19-CAR variants is justified by these molecules' role in the effector activity against neoplastic B cells. The CD19-CAR variants will be constructed to modify the THP-1 monocytic cell line to evaluate in vitro cytotoxic activity against neoplastic B cells through cytotoxicity assays using Raji, Daudi, and Nalm-6 cell lines as target cells. The cytotoxic capacity mediated by the CD19-CAR variants will also be investigated using modified macrophages co-cultured with neoplastic B cells. Therefore, this proposal aims to determine the impact of the Dectin-1, Fc¿R¿1, or Fc¿R1 signaling domain on CD19-CAR, with direct implications for the effector activity of monocytes/macrophages redirected to act against neoplastic B cells.