Controlling infection using NK-92 cells expressing a Chimeric Antigen Receptor (CAR) specific to Aspergillus spp.

• Grant number: 24/19276-0
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2025
• End date: July 31, 2026
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Mobility Program: SPRINT - Projetos de pesquisa - Mobilidade
• Principal Investigator: Thiago Aparecido da Silva
• Grantee: Thiago Aparecido da Silva
• Principal researcher abroad: Pappanaicken Kumar
• Institution abroad: University of Texas MD Anderson Cancer Center (MD Anderson), United States
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated research grant: 18/18538-0 - Bioengineered of T- and NK-cells by CAR against invasive fungal infections, AP.JP

Abstract

Chimeric Antigen Receptor (CAR) therapy is a new approach that utilizes bioengineering to modify immune cells so they are able to specifically target and kill pathogens or altered host immune cells (such as cancers). This approach involves generating modified cell surface molecules (chimeric receptors) and expressing these receptors in host immune cells. As these chimeric receptors recognize a desired target, expression of these receptors enables the modified host cells to specifically kill the invading pathogen or cancerous cell. In a project funded by FAPESP, the da Silva's laboratory has evaluated the capacity of CAR to redirect T and NK cells to target invasive fungal infections. This group has developed different CAR constructs specific for Cryptococcus spp. from monoclonal antibodies (clones 18B7 and 2H1) as a target-binding domain that enables interaction with GXM, called GXMR-CAR. In addition, da Silva's group has advanced in the construction of CAR specific for Candida spp. and Paracoccidioides brasiliensis. These approaches have demonstrated the potential of CAR specific for fungi to redirect T cells and NK-92, favoring the control of fungal infections under study. In this context, Prof. Pappanaicken Kumar's group has acted as a collaborator, and this researcher has as a central focus the development of CAR specific for Aspergillus spp., with pioneering publications in this line of investigation. Aspergillus fumigatus is commonly found in soil and inhalation of conidia allows establishment in the respiratory tract and dissemination to other organs. Immunocompromised individuals are at high risk of invasive aspergillosis characterized by invasion of the hyphal form of A. fumigatus into lung tissue. Aspergillus fumigatus is able to evade recognition by C-type lectin receptors (CLR), such as Dectin-1 and Dectin-2, that could improve the immune response against aspergilosis. These CLR triggers an intracellular signaling pathway that promotes the recruitment of Syk kinase to initiate signaling cascades that activate cellular pathways crucial to induce protective antifungal cell immune responses. The central role of CLR in the construction of CAR specific for A. fumigatus and Candida spp. is the main research focus of the laboratory of Pappanaicken Kumar, who coordinates a leading group investigating cell therapy with CAR technology against invasive fungal infections. In this application, we wish to combine the expertise and research activities of the Kumar and da Silva teams to new CAR constructs specific for Aspergillus fumigatus (AF-CAR) containing Dectin-1 or Dectin-2 as costimulatory molecules, resulting in AF-Dectin-1-CAR and AF-Dectin-2-CAR, to modify NK-92 cells. Previous studies demonstrated an enhanced capacity of C-type lectin receptors signaling pathways to induce the movement of perforin in NK cells, including the NK-92 cell line, toward the contact site with the target cells. Thus, the activation of the Dectin-1 and Dectin-2 signaling pathway will enhance polarization of high levels of perforin to the synapse between NK-92 cells and the fungus, improving the directed cytolysis of the fungal pathogen. The investigators have all the required knowledge to develop the new CARs, moreover, the capacity of Dectin-1 and Dectin-2 to recruit Syk will enable AF-Dectin-1-CAR and AF-Dectin-2-CAR to polarize an augmented production of perforin toward the contact site between modified NK cells and Aspergillus fumigatus. Then, perforin-dependent killing of A. fumigatus by these modified NK-92 cells will be evaluated to control the in vitro and in vivo infection against invasive aspergilosis. (AU)