Analysis of γδ T lymphocytes in Rasmussen's encephalitis

Identifier:  TFG:1633

Handle: https://hdl.handle.net/20.500.11797/TFG1633

Authors:  Vila Borrego, Irene

Abstract:
Rasmussen Encephalitis (RE) is a rare progressive epileptic disorder with unknown aetiology. It is characterized by unilateral hemispheric inflammation, drug-resistant focal epilepsy and progressive neurological and cognitive deterioration. One of the histopathological hallmarks of RE is T cell infiltration, however, little is known regarding their presence in active lesions as well as their phenotype and activation state at early stages of the disease. (Varadkar et al., 2014) In the present study, we analysed in detail the phenotype and activation state of gamma delta (γδ) T lymphocytes in the different stages of RE. Here, specific attention was paid to cytotoxic T cells with the ability to attack neurons, leading to neuronal loss. These studies were performed by qualitative and quantitative analysis by light microscopy and confocal fluorescence microscopy with various markers for T cells. The selection of markers consisted of antibodies against all T cells (CD3) and against γδ T lymphocytes (γδTCR). To identify if γδ T cells have a potential regulatory function, we then analysed the expression of the cytokine gamma-interferon (IFN-γ). IHC stainings showed that γδ T lymphocytes do not constitute a specific population in early stages of RE. Nevertheless, they have the ability of targeting neurons, leading to the conclusion that they are capable of generating neuronal loss. In addition, it has also been proved that they constitute a cell population capable of expressing IFN-γ, suggesting that γδ T lymphocytes might be partially responsible for microglial activation in RE due to the production of this cytokine.