The influence of infectious processes in the hepatotoxicity mediated by iNKT cells

• Grant number: 23/01439-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2023
• End date: December 31, 2023
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Alexandre de Castro Keller
• Grantee: Juliana da Luz Labate
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Liver homeostasis, due to its anatomical structure, depends on the tolerance to microbiota derivatives and immunity to pathogens. In this sense, several studies highlighted the role of invariant T Natural Killer (iNKT) cells in the physiopathology of immune-mediated hepatic diseases. These cells constitute a group of non-conventional T lymphocytes with selectivity for glycolipids expressed in the CD1d molecule. Also, they have a high immunomodulatory potential and are resident cells in different tissues, including the liver. Because the homeostasis of hepatic iNKT depends on the expression of CD1d molecules on the surface of the hepatocytes, we hypothesize that infectious processes can induce changes in both CD1d expression and the lipid antigen class naturally expressed on its groove. Therefore, the present proposal aims to evaluate in vitro the process driving the iNKT-mediated hepatotoxicity upon hepatocyte stimulation with bacterial (LPS) or viral (poly I:C) derivatives. To this end, we intend to take advantage of hepatic cell lines (AML12 and Hepa-1c1c7) and iNKT hybridoma cells (DN3a4-1.2). The experimental parameters are viability assays to characterize hepatotoxicity (LDH, violet crystal, flow cytometry, pCaspase 3-7 by Western Blot); CD1d, Fas, and TRAIL expression using flow cytometric and qPCR assays; and analysis of genes associated with lipid metabolism such as, and not only, Ugcg, B4galt6, and LacCer.Besides the improvement in the knowledge concerning the process driving iNKT-mediated hepatotoxicity and characterization of potential markers for prognostics or intervention, the project is an essential part of the professional development process of the student.