Characterization of the immunomicroenvironment of glioblastoma : Optimization of an antibody panel for detection of glioblastoma TME cells and effect of C3 on glioma cells.

Abstract: Glioblastoma (GBM) is the most common primary brain tumor in adults and represents one of the most aggressive tumor types. Despite treatment GBM remains incurable and when treated the tumor recurs more aggressive and treatment resistant than before. The understanding of the underlying pathophysiology of GBM has increased in recent years, yet the high mortality with a 5-year survival rate of less than 10% remains. Previous studies from the research group, have shown that complement protein C3 is upregulated in stromal and glioma cells in lower oxygen tensions, and this indicates that C3 might play a role in certain GBM tumor microenvironment (TME) niches. For this reason, it is of great interest to investigate how glioma cells are affected when stimulated with C3. With cell proliferation-, migration assays and gene expression analysis with real time quantitative polymerase chain reaction (qPCR) it was possible to investigate how glioma cells respond to treatment with C3 and C3a-receptor antagonist. By optimizing an antibody panel for detection of macrophages/microglia, astrocytes and tumor cells we made it possible to study the modulation of immune parameters during treatment with C3A-receptor antagonist in mice.