Recombinant monoclonal antibodies for therapeutic use

• Grant number: 19/10724-2
• Support type: Scholarships in Brazil - Doctorate (Direct)
• Effective date (Start): June 01, 2019
• Effective date (End): December 31, 2021
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal researcher: Ana Maria Moro
• Grantee: João Victor Batalha de Carvalho
• Home Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 15/15611-0 - Recombinant monoclonal antibodies for therapeutic use, AP.TEM

Abstract

CD3 is a set of three protein chains associated with TCR±:² chains on the T lymphocytes membrane. The CD3 complex is essential for T cells activation and even for its the correct TCR expression. Anti-CD3 monoclonal antibodies (mAbs) have a great potential to treatment autoimmune diseases and induction of tolerance to allogeneic transplants. The original anti- CD3 mAb, produced by a murine hybridoma, present a limited therapeutic use due to adverse reactions induction like T cells proliferation and pro-inflammatory cytokines secretion (i.e. IFN-c and TNF-±). Aiming to avoid immunogenicity issues with non-human molecules, several anti-CD3 mAbs were humanized. The experimental uses of the humanized anti-CD3 mAbs have been associated with increase of both regulatory T lymphocytes (Treg) and immunoregulatory cytokines (i.e. TGF-² and IL-10). To test the immunomodulation potential of clones of humanized anti-CD3 developed at Butantan Institute, São Paulo - SP, this project proposes in vitro assays with lymphocytes from human peripheral blood stimulated by the humanized antibody. The regulator profile x pro-inflammatory profile will be evaluated by the capacity of the antibody to reduce the effector T cells and increase Tregs cellular proliferation. The pattern of secreted cytokines will be assessed by flow cytometry and the expression of regulatory/pro-inflammatory genes by real time PCR. Anti-CD3 induced Tregs will be tested in an in vitro inhibition assay of human effector lymphocytes. All results will be compared with the original murine correspondent expecting to induction a regulatory response by the humanized anti-CD3. (AU)