Year: 2021
Type: dissertation
Abstract: Glioblastoma multiform (GBM) is a lethal brain tumour composed by many distinct cell types that are closely connected and dependent on their surrounding environment. Microglia are the brain immune cells, which are highly abundant in GBM and create an immunosuppressive microenvironment that promotes tumour progression. Caveolin-1 (Cav1) is the most important protein of caveolae and it is involved in cell signalling activity. In the GBM, Cav1 promotes the tumour invasion and it is correlated with a poor prognosis. In immunes cells, its role is not well explored, however it can be involved in immune response. Our hypothesis was that Cav1 could have an impact in the response of human microglia to the environment, influencing tumour progression. \nTo test our hypothesis, a human microglia cell line and an iPSC cell line were used to generate Cav1 knockout clones using CRISPR-Cas9 technology. The iPSC was used to generated human microglia cells. \nPrimary human microglia expressed low levels of Cav1, which could be regulated upon activation. The viral immortalized human microglia cells expressed strong Cav1 protein levels, possibly correlated with the immortalization procedure with SV40 large T antigen. This infection in combination with the culture conditions might lead to a constitutive pro-inflammatory phenotype, impacting the ability of microglia to react to other stimulus and to do phagocytosis. A slightly modified protocol to generate microglia from iPSC allowed the differentiated cells to be polarized towards pro-inflammatory and anti-inflammatory phenotype and to perform phagocytosis. \nIn microglia, Cav1 was involved in the regulation of the inflammatory response, cell migration, phagocytosis, and sensitivity to temozolomide. The microglia cell line did not impact the tumour behaviour, likely due to the profile presented by the cells. However, the deletion of Cav1 in microglia derived from iPSC promoted the tumour invasion.
Author: Catia Das Neves Neto
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W3175286938