Comparative analysis of cell signaling in epithelial cells cultured as monolayer or spheroids in the presence of conditioned medium of Paracoccidioides brasiliensis

Abstract

The lung epithelial cells play an important role in the immune system by producing cytokines and chemokines that act as chemoattractants for the recruitment of immune cells against stimuli. The modulation of these cytokines may occur by integrins, which are membrane proteins that participate in the pathogen-host interactions. Our group studies the interaction between epithelial cells and the human fungal pathogen Paracoccidioides brasiliensis. Recently, we showed that cultivating A549 cells as a monolayer, ±3 and ±5 integrins are involved in the secretion of IL-6 and IL-8 against P. brasiliensis. Likewise, we showed that secreted factors present in conditioned medium of P. brasiliensis also promote an increase of these cytokines levels by A549 cells.Three-dimensional (3D) cell culture models have been used to study the cell behavior by providing a similar structure to in vivo conditions. Several groups have compared monolayers (2D) and 3D cell cultures and results were different regarding cell growth, migration, drug response and cell signaling. About integrin, some studies showed a different pattern expression of these proteins when cells are cultured as monolayers (2D) or as spheroids (3D).Although 3D cell culture models mimic physiological tissues in a more reliable way, when compared to 2D cell culture models, the knowledge about changes in cell response in the presence of fungal pathogens are scarce. Therefore, the main goal of this project is to compare IL-6 and IL-8 secretion by A549 cells in both monolayer (2D) and 3D cultures after P. brasiliensis conditioned medium stimulation. In addition, we will verify the ±3 and ±5 integrins signaling pattern and the interaction with other cell types (lung fibroblasts and dendritic cells). (AU)