Optimization of CAR-T cell Function and Infiltration in the Treatment of Renal Carcinomas

• Grant number: 23/00925-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: March 01, 2024
• End date: July 31, 2027
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Eloah Rabello Suarez
• Grantee: Najla Santos Pacheco de Campos
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil

Abstract

T cells expressing chimeric antigen receptors (CAR T cells) have demonstrated remarkable clinical efficacy in treating different hematologic tumors. However, several challenges must be overcome to allow similar efficiency against solid tumors. Among these challenges, two points are remarkable: the inefficient migration of LT CAR to tumor sites and the frequent local immunosuppression that limits T cell cytotoxic activity. Several hypoxic tumors and especially clear cell renal carcinoma (ccRCC) express high amounts of an enzyme called carbonic anhydrase IX (CAIX), which is considered an interesting tumor-associated antigen for CAR T cell development. This project presents two integrated aims, the first being the evaluation of anti-tumor effects of CAIX-targeted CAR T cells containing CD28 or 4-1BB as costimulatory domains and capable of inducing different levels of T cell exhaustion in a patient-derived ccRCC xenograft model (PDX). The second aim consists of adapting CAR T that demonstrate greater efficiency in previous models to co-express integrin-modulating enzymes in the second cassette of the same CAR carrier lentivector, through molecular cloning. Such enzymes can remodel the cytoskeleton of immune cells by modifying integrins, promoting adhesion and transendothelial migration of T cells towards the tumor. The lentiviruses will be produced by transient transfection, concentrated, titrated, and transduced into T cells CD4:CD8 2:1 purified from the mononuclear fraction of the blood of healthy donors. The resulting CAR T cells will be expanded, and their transduction levels will be accessed in the short and long term. The Anti-CAIX CAR T cells CD28 and 4-1BB will be evaluated in vivo in a ccRCC PDX model, determining the exhaustion status of tumor-infiltrating T cells. The Anti-CAIX CAR T cells expressing remodeling enzymes will be tested in vitro for enzymatic activity, transendothelial migration and cytotoxicity of ccRCC cells and in vivo in a humanized orthotopic model of ccRCC and/or PDX, determining the amount and activation status of tumor-infiltrating CAR T cells. This project has the potential to solve one of the main current challenges of CAR T therapy against solid tumors, boosting the infiltration and optimizing the performance of CAR T in the tumor microenvironment.