Modulating immune responses by targeting protein aggregation

• Autor(a) principal: Carvoeiro, Daniela Claudino
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/28429
• topic: pDC; Inflammatory response; Protein aggregates; DALIS; Proteasome; p62; Inflammasome

Protein aggregation is induced by a wide variety of cellular stresses, including amino acid starvation, virus infection, endoplasmic reticulum stress, lipopolysaccharide, and oxidative stress. It has been suggested that altered proteostasis impacts the inflammatory response, but the underlying mechanism between altered proteostasis and inflammation is still poorly understood. Here, we aim to analyse the impact of protein aggregation in the response of human Dendritic Cells, focusing on plasmacytoid dendritic cells (pDCs). The number of aggregates was manipulated in a pDC cell line, CAL-1, by using both autophagy and proteasome inhibitors. Proteasome inhibition in pDCs induced assembly of large p62-based aggregates, together with an increase on IL-1β secretion and cell death, in an irreversible and cell specific manner. The same effects were not observed upon autophagy inhibition nor on a monocytic cell line. To study the mechanism behind the increase in the inflammatory response upon proteasome inhibition, p62-knockout cells were generated using the CRISPR/Cas9 system. Our data suggests that neither p62 nor the NLRP3 inflammasome are required for induction of cell death upon proteasome inhibition in pDCs. Overall, we conclude that proteasome inhibition induces an inflammatory response specific to pDCs. We propose that this effect must be considered when using proteasome inhibitors as potential drugs for the treatment of pDCs derived immune-mediated disorder and thus, mores studies should be done to clarify the outcome of proteasome inhibition on pDCs.