RESUMO
OBJECTIVES: The fate choice of neural progenitor cells could be dictated by local cellular environment of the adult CNS. The aim of our study was to investigate the effect of hippocampal tissue on differentiation and maturation of oligodendrocyte NG2 precursor cells. MATERIALS AND METHODS: Hippocampal slice culture was established from the brains of 7-day-old rats. NG2 precursor cells, obtained from a 12-day-old mixed primary culture of neonatal rat cerebral hemispheres, were labelled with chloromethyl-fluorescein-diacetete and seeded on the hippocampal slices. After 7-14 days in co-culture, cells were stained with neural markers. RESULTS: NG2 cells differentiated predominantly into oligodendrocytes, presenting various stages of maturation: progenitors (NG2), pre-oligodendrocytes (O4) and finally mature GalC-positive cells. However, except for a few cells with astrocyte-specific S100b staining, a considerable number of these cells differentiated into neurons: TUJ(+) and even MAP-2(+) cells were frequently observed. Moreover, a certain population of these cells preserved proliferative properties of primary precursor cells, as revealed by Ki67 expression. CONCLUSIONS: The neuronal micro-environment provided by the culture of hippocampal slices is potent for induction of neurogenesis from oligodendrocyte NG2(+)/PDGFRalpha(+)/CNP(+) progenitor cells and promotes their differentiation not only into macroglia but also into neurons. It also sustains their proliferative capacity. The results indicate the crucial role of the local cellular environment in fate decision of primary NG2(+) multipotent neural progenitor cells, which may affect their behaviour after transplantation into the central nervous system.
Assuntos
Hipocampo/citologia , Neurônios/citologia , Oligodendroglia/citologia , Células-Tronco/citologia , Animais , Animais Recém-Nascidos , Antígenos/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Fatores de Crescimento Neural/metabolismo , Técnicas de Cultura de Órgãos , Proteoglicanas/metabolismo , Ratos , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/metabolismo , Células-Tronco/metabolismoRESUMO
In vitro studies conducted by our research group documented that neural progenitor cells can be selected from human umbilical cord blood (HUCB-NPs). Due to further expansion of these cells we have established the first human umbilical cord blood-derived neural-like stem cell line (HUCB-NSC) growing in serum-free (SF) or low-serum (LS) medium for over 3 years. The purpose of the study was to evaluate the neurogenic potential of HUCB-NSCs cultured in SF and LS condition in different in vitro settings before transplantation. We have shown that the number of cells attaining neuronal features was significantly higher for cultures expanded in LS than in SF condition. Moreover, the presence of neuromorphogens, cultured rat astrocytes or hippocampal slices promoted further differentiation of HUCB-NSCs into neural lineage much more effectively when the cells had derived from LS cultures. The highest response was observed in the case of co-cultures with rat primary astrocytes as well as hippocampal organotypic slices. However, the LS cells co-cultured with hippocampal slices expressed exclusively a set of early and late neuronal markers whereas no detection of cells with glial-specific markers was possible. In conclusion, certain level of stem/progenitor cell commitment is important for optimal response of HUCB-NSC on the neurogenic signals provided by surrounding environment in vitro.
Assuntos
Sangue Fetal/fisiologia , Neurônios/fisiologia , Células-Tronco/fisiologia , Animais , Astrócitos/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Contagem de Células , Células Cultivadas , Meios de Cultura , Proteínas de Ligação a DNA/genética , Proteína Glial Fibrilar Ácida/genética , Proteínas HMGB/genética , Hipocampo/citologia , Hipocampo/fisiologia , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Proteínas Associadas aos Microtúbulos/genética , Fator 3 de Transcrição de Octâmero/genética , Fatores de Transcrição Otx/genética , Fenótipo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1 , Fatores de Transcrição/genética , TransfecçãoRESUMO
73 expectant mothers from 7 to 37 weeks of pregnancy were divided into 4 groups according to their pregnant age. The women were clinically and sonography examined with endovaginal transducer. The main aim of these examinations was comparison of the results of cervix efficiency. In this sonography scanning were estimating the length, the width of the cervix canal and the width of internal os. Having done the examinations we discovery interdependence the cervix parameters of the age of pregnancy it also proved the great worth of endovaginal ultrasonography as a verification of the clinical examination.
