In vivo study of the therapeutic potential and characterization of murine/chimeric anti-IL7Ra antibodies in Pediatric Leukemia treatment

• Grant number: 23/11203-1
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: December 01, 2024
• End date: July 31, 2028
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal Investigator: Priscila Pini Zenatti Salles
• Grantee: João Mateus Silva Feitoza
• Host Institution: Centro Infantil de Investigações Hematológicas Dr Domingos A Boldrini (CIB). Campinas , SP, Brazil

Abstract

The lymphoid leukemias are hematologic neoplasms in the B and T lineages and are the major cause of infant death caused by cancer. About 10% of the ALL-T and 2% of the ALL-B present a leukemogenic mechanism caused by activating mutations in the gene encoding the hIL7R± protein (± chain of the human 7 interleukin receptor). The IL7R± is a protein expressed on the lymphocyte surfaces, it is responsible for development and maturation of these cells and it can present an oncogenic potential when mutated. Therefore, the block of this interleukin and of its signalization way, indicates a therapeutic strategic potential in childhood leukemia. Our research group obtained 3 antibody clones (hybridomas) with anti-IL7R± specificity and demonstrated, in preliminary results, significant therapeutic potential in immunodeficient mice transplanted with pediatric leukemias. Furthermore, we have another 2 chimeric antibodies, obtained by NGS Sequencing of the immunized mice antibody repertoire, and showed affinity with our target of interest. Thus, this project proposes to: (1) Study the therapeutic potential of the three murine antibodies, using them single agents, in the coquetel form, and in combination with chemotherapy on distinct pediatric ALL subgroups; (2) Synthesize the chimeric versions (cAb) of the 3 reagents, as well as of the two antibodies obtained by NGS; (3) Study the mechanism of the cAb as for influence on IL7R-IL7 binding, f cytotoxicity action, and their effect on the IL7R/Jak/STAT signaling pathway; (4) Confirm the therapeutic potential of the 5 cAb in vivo, in transplanted NSG mice with leukemia cellular lineage; (5) Produce vesicles from doxorubicin encapsulating liposomes and coated with the best Ab for treatment, aiming a driven delivery strategy; (6) Perform a comparative preclinical trial of the treatment with nanoformulation (liposome + doxo + anti-IL7R±) vs the antibody + doxo treatment. The project also proposes to request a BEPE to realize one year of internship in the Ph.D Scott Durum's laboratory (NIH - USA). We will do a collaboration with the Ph.D Josimar Eloy as well from UFC to produce nanocapsules. At the end of the project, we hope to have validated the therapeutic potential of these anti-IL7R± antibodies in distincts ALL subgroups, as well as having identified their mechanisms of action and evidenced a new strategy of chemotherapy delivery more efficiently. These outcomes will be fundamental to optimization of humanized versions of these reagents that can be evaluated in clinical trials with pediatric patients. significant therapeutic potential in immunodeficient mice transplanted with pediatric leukemias. Thus, this project propose: (1) study in detail the therapeutic potential of the three antibodies, using them in isolation and in coquetel form; (2) assess the effects in combination with chemotherapy on distinct pediatric ALL subgroups; (3) study the mechanism of action these antibodies - influence on IL7R-IL7 binding, existence of cytotoxicity action (ADCC, CDC) and its effect on IL7R/Jak/STAT signalizing way; and (4) synthesize the chimeric versions of the 3 reagents and test them in vivo, in transplanted mice with leukemic cellular line. At the end of the project, we hope we have validated the therapeutic potential of these monoclonal antibodies to distincts ALL subgroups, as well as having identified them mechanisms of action. These outcomes will be fundamental to optimization of humanized versions of these reagents that will be used in the clinical assays with the pediatric patients.