Characterization of ovine mesenchymal stem cells and development of in vitro cellular models of prion diseases

Identifier:  TFG:2122

Handle: https://hdl.handle.net/20.500.11797/TFG2122

Authors:  García Rey, Andrea

Abstract:
Transmissible spongiform encephalopathies (TSEs) are a group of lethal neurodegenerative diseases caused by the accumulation of prion protein in their pathological isoform (PrPSc) in the neuronal cells. The unknowledge of the molecular mechanisms and the absence of specific treatment, requires the creation of cellular models that allow to study the TSEs. The main goal of this Final Degree Project is evaluate the potential of mesenchymal stem cells (MSCs), of different genotypes for the PRNP gene, for the development of in vitro models of TSEs. It were used three cultures of MSCs, whose mesenchymal origin was confirmed by studying their adipogenic, chondrogenic and osteogenic differentiation ability and the expression of some specific surface markers. The plasticity of the MSCs was assessed by the differentiation ability onto neural stem cells (NSC) under monolayer growth conditions (NSCs) and neurosphere formation (MSC-NP). The MSCs were subjected to infectivity studies in basal and differentiation conditions towards NSCs, with sheep brain extract infected with Scrapie carrying different genotypes for PRNP. The MSCs were able to differentiate into adipocytes, chondrocytes and osteocytes but the expression of surface markers was variable. Differentiation towards NSC in monolayer growth showed changes in cell morphology, although the analysis of the intracellular marker did not validate the differentiation. In the formation of neurospheres, the low expression of mesodermal lineage genes evidenced the loss of characteristics of mesodermal origin in differentiated cells. In both growth conditions, scrapie inoculation induced the cell proliferation in all cultures with different genotype. Results on prion multiplication varied depending on the cell genotype.