Effects of the Pseudomonas aeruginosa quorum sensing molecule 3-oxo-C12-HSL on T cell activation in lung epithelial cell 3D organoids

• Grant number: 21/11012-6
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: October 03, 2022
• End date: October 02, 2023
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal Investigator: Niels Olsen Saraiva Câmara
• Grantee: Marcella Cipelli
• Supervisor: Matthias Lochner
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Hannover Medical School, Germany
• Associated to the scholarship: 18/24350-4 - Metabolic characterization of Foxp3+ RORgt+ T cell population in the experimental model of Colitis-associated colorectal Cancer, BP.DD

Abstract

Pseudomonas aeruginosa infection in Cystic Fibrosis (CF) patients is associated with disease progression and morbidity. One important pathogenicity factor is the production of the quorum-sensing molecule 3-oxo-C12-HSL, which was shown to be detrimental to epithelial cell barrier integrity as well as metabolism. In recent years the importance of tissue-resident memory T cells in lung infections was realized. These cells display a variety of inhibitory receptors, while they were shown to mount strong immune responses upon reactivation. In CF patients a hyper-inflammatory state and a T cell response prone to Th17 cells are found. We hypothesize that 3-oxo-C12-HSL impairs the expression of inhibitory signaling molecules on epithelial cells and increases activating stimuli leading to enhanced TRM reactivation. We will conduct FACS and microscopy analysis of epithelial cells cultured in 3D human lung organoid structures, established in the lab, to analyze the expression of the inhibitory molecule PD-L1 of 3-oxo-C12-HSL-treated cells. Moreover, we will examine cytokine production and MHC expression. To confirm findings, we will co-culture T cells in murine organoids and check for reactivation in the presence of 3-oxo-C12-HSL upon LPS stimulation to understand the hyper-inflammatory status of CF lungs is of key importance to explore new therapeutic targets. Blockade of bacterial substances associated with these immune responses would be beneficial as side effects may be minor compared to influencing host cells. We hope to connect 3-oxo-C12-HSL with increased T cell reactivation and thereby pave the way to new treatment options in CF patients. (AU)