Functional characterization of rare variants in the mitochondrial and inflammatory genes identified in CCC cases using CRISPR-Cas9 engineered AC-16 cardiomyocytes and THP1 monocyte-like cells

• Grant number: 23/02141-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): May 01, 2023
• Effective date (End): March 31, 2024
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal Investigator: Edecio Cunha Neto
• Grantee: Rafael Pedro Madeira da Silva Souza
• Host Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 22/00758-0 - Mitochondria, interferon-gamma and genetics in Chagas Disease cardiomyopathy: pathogenesis, therapeutic targets and prognostic markers, AP.TEM

Abstract

About 30% of Chagas disease patients develop chronic Chagas disease cardiomyopathy (CCC), an inflammatory cardiomyopathy that occurs decades after the initial infection, while most infected patients (60%) remain asymptomatic in the so-called indeterminate form (IF). Myocardial fibrosis, inflammation and mitochondrial dysfunction are involved in the arrhythmia substrate and triggering events. Survival in CCC is worse than in other cardiomyopathies. CCC displays a Th1-T cell rich myocarditis with abundant IFN-gamma and TNF-alpha, and selectively lower levels of mitochondrial energy metabolism enzymes in the heart. IFN-gamma and TNF-alpha signaling, which are constitutively upregulated in CD patients, negatively affect mitochondrial function. A genetic component in disease susceptibility was suggested by case-control studies that identified gene polymorphisms associated to CCC development. Whole exome sequencing (WES) in nuclear families with multiple CCC/IF cases has disclosed rare heterozygous pathogenic variants in mitochondrial and inflammatory genes segregating in CCC cases. We will explore the pathophysiology of mitochondria and cytokines in CCC by performing functional studies with CRISPR-Cas9-gene edited cardiomyocyte cell lines carrying or not the variants of interest under the effect of IFN-gamma and TNF-alpha.