Caracterización molecular de células progenitoras del parénquima subcortical cerebral humano adulto / Molecular characterization of progenitor cells from subcortical parenchyma of adult human brain

Objetivo: Caracterizar los patrones de expresión de marcadores de indiferenciación y diferenciación y las alteraciones morfológicas de las células progenitoras procedentes de parénquima cerebral humano adulto a lo largo de los pases en cultivo, evaluando su potencial para ser empleadas como fuente de progenitores de oligodendrocitos. Materiales y Métodos: Las células progenitoras se aislaron a partir de dos muestras obtenidas de pacientes sometidos a exéresis temporal por epilepsia. Para comprobar la evolución de los niveles de expresión de marcadores moleculares de diferenciación e indiferenciación en dichas células, se procedió a la extracción de ARNm en cada pase y a su estudio mediante RT-PCR. Se llevó a cabo un análisis de su capacidad proliferativa mediante inmunocitoquímica y un estudio de la evolución morfológica mediante microscopía. Resultados: Las células mostraron capacidad proliferativa durante los primeros pases en cultivo. Además, detectamos la expresión de marcadores de indiferenciación y diferenciación temprana a oligodendrocitos. Conclusión: Las células progenitoras aisladas de parénquima subcortical de cerebro humano pueden ser susceptibles de diferenciación a oligodendrocitos maduros, aunque en protocolos de diferenciación sólo deberían utilizarse pases tempranos (AU)

Objetive: characterize the behavior of progenitor cells isolated from subcortical parenchyma of human brain in culture. We have analyzed the changes in expression patterns of differentiation/undifferentiation markers as well as cell morphology along the passages and evaluated the potential to be further used as oligodendrocyte progenitors source. Material and Methods: We isolated progenitor cells from two different samples of subcortical parenchyma human brain of patients suffering from epilepsy. Cells were kept in culture until they became quiescent/senescent. Every other passages RNAs were isolated and checked for the expression of differentiation and undifferentiation markers by using RT-PCR. Proliferation was also addressed by RT-PCR and immunocytochemistry. We carried out cell morphology studies on semithin and ultrathin sections of cells. Results: We observed decreasing proliferative capacity of both two cell lines which became quiescent/senescent around passages 8-10. We detected the expression of either undifferentiation or early neural and oligodendrocytes differentiation markers. Conclusions: As for the expression of molecular markers, progenitor cells isolated from subcortical parenchyma of human brain have the potential to differentiate into mature oligodendrocytes (AU)

Proliferation in the human ipsilateral subventricular zone after ischemic stroke.

BACKGROUND: It is uncertain whether neurogenesis occurs in humans after stroke. We studied the morphologic changes that occurred in the subventricular zone (SVZ) in patients who died following an acute ischemic stroke. METHODS: We examined coronal brain slices from patients who died after a first-ever cerebral nonlacunar infarction in the middle cerebral artery territory. We evaluated the morphologic changes in the ipsilateral and contralateral SVZ by light and electron microscopy. Using immunochemistry with Ki-67 and PCNA, we detected cell proliferation. We used Tuj-1 for immature neurons and PSA-NCAM for migrating cells. RESULTS: The study included 7 patients with a mean age of 82 +/- 5 (mean +/- SD) years; 4 were men. They died a mean of 10 +/- 5 days after the ischemic stroke. Brain samples were obtained a mean of 4 +/- 2 hours after death. In comparison with the contralateral SVZ, the following changes were observed in the ipsilateral SVZ: an increase in the width of the gap and ribbon layers, as well as in the cell density of the ribbon layer, an enlargement of the cytoplasmic volume of astrocytes, and an increase of Ki-67-positive cells. In the ipsilateral SVZ, mitoses and cells that stained for either Tuj-1 or PSA-NCAM markers were observed more frequently than in the contralateral SVZ. CONCLUSION: We found unequivocal evidence of active cell proliferation in the ipsilateral subventricular zone following an acute ischemic stroke in our patients.