Using primary mouse microglia to investigate the role of C5a in inducing an inflammatory response to Aβ

Identifier:  TFG:105

Handle: https://hdl.handle.net/20.500.11797/TFG105

Authors:  Marsal Cots, Anaïs

Abstract:
The macrophages of the brain’s innate immune system, microglia, represent around 10% of the total cells in the nervous system. Microglial cells suffer a rapid transformation from a quiescent to an activated phenotype to respond to pathological affairs, and this phenotype is characterized by increased cytotoxicity and motile activity. Complement activation products, including C5a, are thought to play a role in the pathogenesis of numerous neurological diseases. Primary neuronal and microglia cultures prepared from rodent nervous tissues represent a powerful tool not only to study the individual contribution of different cell types (such as neurons or glia) to disease progression, but also to investigate the role of neuron-glia interactions during development and pathogenesis of disease. It is known that fAβ has some toxic effects on neurons directly, but the strong presence of activated microglia at sites of fAβ deposits in AD suggest that these cells may also be contributing to the progression of the disease. In vitro cultured microglia release nitric oxide when fAβ and other co-stimulatory molecules such as IFN-γ or LPS are added. Primary neonatal microglia cultures were treated with or without C5a in the presence or absence of fAβ1-42 20μM in order to determine if C5a can synergistically enhance the production of NO elicited by fAβ. Although microglial cells are a heterogeneous and extremely sensitive population, in most of our experiments we found a synergistic response in cells treated with fAβ and C5a, thus supporting our hypothesis that C5a and fAβ synergize to enhance nitric oxide production. However, variability of the results obtained along the experiments performed can be explained by the fact that microglia are extremely sensitive to minor alterations on the CNS microenvironment.