Modelo celular de autismo

Zusammenfassung

ASD is a functional alteration of the cerebral cortex, which presents structural neurodevelopmental anomalies that affect the disposition of neurons, as well as the synaptic function and the pattern of connections within and between cortical columns. From its etiological aspect, ASD has an important genetic load, considering a polygenic disorder, derived from a combination of "de novo" genetic alterations (spontaneous mutations), associated to a predisposition derived from common inherited variations. The main genetic anomalies associated with ASD involve genes that encode proteins of the synapse. In general, they are genes linked to the establishment, maintenance of synapses and synaptic plasticity. Thus, in patients with ASD, alterations in the initial development of the synapses have been described in the connection circuits between complex processing cortical areas (which receive and process multimodal information in combination). The molecular complexity observed in the predisposition to develop an ASD, together with the diversity of neuronal structural phenotypes, has made animal models reproduce only partially the ASD. To advance in the experimental study it is therefore necessary to develop more representative models, such as cellular models derived from human cells. In recent decades, the development of the biology of stem cells gives us the means to access experimental paradigms about cells derived from individuals with ASD. Currently, IP cell models derived from human cells allow to deepen the molecular and cellular bases of the development of the human brain, as well as the anomalies in this development, which give rise to disorders such as ASD. However, they present inherent problems derived from the experimental manipulation that involves the reprogramming of gene expression. We propose as a general objective to develop a cellular model of ASD, generating mesenchymal cell cultures derived from the periodontal ligament (LP) and dental pulp (PD) of teeth of people with autism, to look for cellular and molecular markers of the disease. For what we propose the following specific objectives: 1. Isolate and amplify mesenchymal stem cells of LP and PD from samples with ASD and controls. 2. Define the cellular and molecular characteristics of these cells. 3. Know the neural potential of these cells. 4. Compare the properties of neuronal cells derived from LP and PD with ASD with cells from control individuals. We have extracted, cultured and selected mesenchymal cells from LP and PD controls and with ASD. Once the cultures have been amplified, the cells have been induced to differentiate as neurons (passing them to neurogenic medium). We have carried out studies of proteomics (immunocytochemistry and Western blot) and transcriptomics (qPCR), showing the molecular and cellular characteristics of the PD and PD control cells and with ASD. The results have shown that: 1. Mesenchymal stem cells of LP and PD can be isolated and amplified from samples with ASD and controls. 2. LP and PD cells with ASD and controls have the ability to differentiate into neurons and we have defined the stages of the differentiation process. 3. We can say that neurons derived from mesenchymal cells with ASD present "in vitro" an alteration in the expression of genes and synaptic proteins. These alterations highlight an anomalous distribution of presynaptic markers, together with an alteration in the expression of postsynaptic density proteins.