Biomedical subjects

A V Revishchin

Publications and source records attributed to A V Revishchin.

At least 19 recordsLinked to original sources

PubMed2006

Neural stem cells and their role in recovery processes in the nervous system.

Published data and our own results on the identification, cultivation, and potential therapeutic utilization of regional stem cells from humans and animals are reviewed. Pluripotent stem cells have been shown to proliferate in the subventricular zone of the lateral ventricles and the subgranular zone of the dentate gyrus of the hippocampal formation in adult human and animal brains. Data on the hierarchical organization of genetic networks in controlling individual development suggest a possible functional role for repeat mini-and microsatellite DNA sequences in stem cell differentiation. Methods of using human bone marrow as a source of stem cells for restoring damaged tissue in the brain are discussed. Heat-shock proteins have been found to block the formation of glial scars after neural transplantation. The viability of stem cells after transplantation can be increased by transfer of genes for neurotrophic growth factors into the genomes of the neurons undergoing transplantation.

Animals↗

PubMed2005

Characteristics of human neural stem cells in vitro and after transplantation into rat brain.

We studied the effect of culturing conditions on the fate of human neural stem cells after transplantation into rat brain. Human neural stem cells cultured in the presence of mitogens without LIF migrated along the ependyma and cerebral vessels of recipients, but to a great extent degenerated by the 20th day after transplantation. Neural stem cells cultured with LIF migrated, apart from the above mentioned pathways, in the cortex and hippocampus, well survived; proliferating cells were retained 30 days after transplantation.

Animals↗

PubMed2005

Human fetal neural stem cells in rat brain: effects of preculturing and transplantation.

The fate of human fetal stem/progenitor cells transplanted into rat brain depends on conditions of preculturing (long or short) and state and site of transplantation. Human nestin-positive stem cells cultured according to the short protocol did not migrate into hypoxic and normal brain after transplantation, but actively migrated in damaged spinal cord. After transplantation of long-cultured cells into the brain mainly committed neuroblasts and solitary nestin-positive cells migrated from the site of transplantation into the brain.

Animals↗

PubMed2005

BFP protein expression in transfected embryonic stem cells.

Cultured mouse embryonic stem cells can be transfected with a reporter gene encoding blue fluorescent protein BFP and regulated by drosophila heat shock protein 70 promoter. This gene is activated after heating and synthesizes matrix RNA. Blue protein is synthesized under these conditions. The system for transfection of stem cells allows us to activate automatically the corresponding transgenes.

Animals↗

PubMed2005

[Neural stem cells and their significance in regeneration processes in the nervous system].

This review includes the literature data and the results of authors' own investigations on identification, cultivation and perspectives of therapeutic application of human and animal regional stem cells. Proliferation of pluripotent stem cells is observed in subventricular area of lateral ventricles and subgranular layer of dentate fascia of hippocampal formation of adult brain of man and animals. Data on the hierarchical organization of gene networks in the regulation of individual development may point to a possible functional role of repeating mini- and microsatellite DNA sequences in stem cell differentiation. The variants of application of human bone marrow as a source of stem cells for repair of damaged brain tissues are considered. It is established that heat shock proteins block the formation of glial scar during neurotransplantation. The viability of stem cells during transplantation may be improved by insertion of genes for neurotrophic growth factors into a genome of transplanted neurons.

Animals↗

PubMed2004

Transplantation of cultured neural cells from human fetuses into the brain of rats exposed to acute hypoxia.

Neural stem cells of human brain were cultured for a long time and successfully transplanted into the brain of rats exposed to acute hypoxia. Stem and committed cells, neuroblasts, and astrocytes were revealed in transplants by immunohistochemical assay. The transplants and brain tissue were not separated with a glial barrier. Human neuroblasts widely migrated into regions of neuronal degeneration in the host brain.

Animals↗

PubMed2004

Human neural stem cells normalize rat behavior after hypoxia.

Transplants of cultured neural stem cells from human brain survived, retained multipotent activity, and produced a neuroprotective effect on degenerating neurons in the brain of adult rats subjected to hypoxic hypoxia. They normalized animal behavior and improved conditioning in two-way avoidance response paradigm in a shuttle box.

Animals↗

PubMed2004

Immunohistochemical study of fetal stem/progenitor cells from human brain transplanted into traumatized spinal cord of adult rats.

Neural stem/progenitor cells from human fetal brain were grown in a tissue culture and transplanted into traumatized spinal cord of adult rats. The behavior and differentiation of transplanted cells were studied morphologically by means of histological and immunohistochemical methods and confocal microscopy. Human neural stem/progenitor cells were viable for not less than 3 months. They migrated and differentiated into neurons and glia in the traumatized spinal cord of adult rats.

Animals↗

PubMed2004

Development of neural stem/progenitor cells from human brain by transplantation into the brains of adult rats.

The aim of the present work was to study human neural stem/progenitor cells (SPC) cultured in vitro and their potential to survive, migrate, and differentiate after transplantation into adult rat brain. SPC were extracted from the brains of nine-week human embryos and were cultured in selective medium for three weeks. Transplantation was with suspensions of cells or whole neurospheres; these were studied four weeks after transplantation into the hippocampus, striatum, and lateral ventricles of adult rats. Analysis of transplanted cells was based on various histological and immunohistological staining methods: bisbenzimide, bromodeoxyuridine, and antibodies to human nuclei, vimentin, beta-tubulin, neurofilaments, and glial fibrillar acidic protein, which allowed us to make independent assessments of their state and differentiation. Transplanted SPC from human brains survived well for one month in all areas of adult rat brain without immunosuppression. Cells from suspension transplants migrated intensely and differentiated into neurons and gliocytes. At the same time, transplants of whole neurospheres showed limited or no migration because of the development of a glial barrier.

Animals↗

PubMed2003

Xenotransplantation of embryonic precursors of human myogenesis for the correction of dystrophinopathy in mice with hereditary muscular dystrophy.

Human embryonic myogenic precursors were transplanted into muscles of mdx mice with hereditary dystrophin-deficient muscular dystrophy. Transplantation induced the synthesis of human dystrophin. The number of dystrophin-positive fibers progressively decreased, however, some of them were preserved even 5 months after transplantation. Our results indicate that xenogeneic transplantation of embryonic myogenic precursors compensates the genetic defect in dystrophin-deficient mice.

Animals↗

PubMed2003

[Development of human brain neural/progenitor cells after transplantation into the brain of adult rats].

The purpose of the present study was the investigation of human neural stem/progenitor cells (SPC) cultured in vitro, with special reference to their capacity for grafting, migration and differentiation after transplantation into adult rat brain. SPC were isolated from the brain of 9-week-old human embryos and were cultured in a selective medium for 3 weeks. For transplantation, cell suspension or whole neurospheres were used; they were studied 4 weeks following the transplantation in hippocampus, striatum and lateral ventricle of adult rat brain. For the analysis of transplanted SPC, various histological and immunohistochemical staining methods were applied (bisbenzidine, BrdU, antibodies against human nuclei, vimentin, beta-tubulin, neurofilaments, GFAP), that allowed an independent evaluation of their state and differentiation. Transplanted human brain SPC were shown to survive well for one month in all the areas of adult rat brain without immunosuppression. Cells from suspension transplants actively migrated and differentiated into neurons and glial cells. Meanwhile, cell migration from the transplanted whole neurospheres was limited or absent due to the formation of glial barrier.

Animals↗

PubMed2002

Behavior of human neural progenitor cells transplanted to rat brain.

Human neural stem/progenitor cells provide a useful tool for studies of neural development and differentiation, as well as a potential means for neuroreplacement therapeutic needs in the human CNS. Stem cells isolated from developing human central nervous system of 8-12-week fetuses were transplanted to the forebrain and cerebellum of young and adult rats after 14 days of in vitro expansion. Cells were labeled by bisbenzimide prior to transplantation without immunosuppression. Recipient brains were examined 10 and 20 days after transplantation. Labeled stem cells were found in the neocortex, lateral ventricle and caudate nucleus in the forebrain, and in the molecular layer, Purkinje cell layer, and granular layer of the cerebellum. Mitotically dividing stem cells were observed in graft core, confirming their proliferative potential in new microenvironment. Engrafted cells migrate through the parenchyme of striatum, along the ventricular ependymal layer and callosal fibers, some of them reaching the opposite hemisphere. Some cells migrating along the capillaries express glial acid fibrillary protein, demonstrating their differentiation into astrocytes. Grafted cells expressing calbindin were found in the Purkinje cell layer, suggesting their differentiation into the Purkinje cells. At the same time, some grafted cells were undifferentiated and expressed vimentin. Our results demonstrate that cultured human neural stem/progenitor cells migrate and differentiate into both neurons and astrocytes after transplantation to the rat forebrain or cerebellum of young and adult rats.

Animals↗

PubMed2002

Evaluation of progenitor cell cultures from human embryos for neurotransplantation.

Human neural stem cells (HNSCs) are used in studies of neural development and differentiation, and are regarded as an alternative source of tissue for neural transplantation in degenerative diseases. Selection and standardization of HNSC samples is an important task in research and clinical approaches. We evaluated embryonal brain matter obtained from human 8-12-week-old fetuses by means of flow cytometry on a panel including: nestin; vimentin; NeuN; GFAP; beta-tubulin III; CD56; N-Cad; OB-Cad; HLA-ABC; HLA-DR; CD34, and annexin. Samples from embryos of even the same gestation differ dramatically regarding neural cell development, their phenotype and viability. The samples containing the highest proportion of stem cells and multipotent progenitors of neural types, and the least of definitive cells and antigens of histocompatibility, were selected for further expansion in serum-free medium. Secondary phenotyping 14 days later revealed again a marked heterogeneity of the cultures. For the final culturing for 24 h in a serum-containing medium we selected only samples having following phenotype: nestin+, and vimentin+ no less than 25%; HLA-DR+ and CD34+ no more than 5%; GFAP+ no more than 10%; beta-tubulin+ no more than 20%; CD56+, N-Cad+, OB-Cad+, HLA-A,B,C+, and annexin+ no more than 15%; cell viability no less than 60%. Immunocytochemical study of selected samples proved that numerous neural stem cells, and neuro- and glioblasts necessary for transplantation were present. Our results demonstrate that the flow cytometry phenotyping allows the screening and standardization of HNSC samples for further expansion and transplantation.

Brain↗

PubMed2002

[Induction of murine bone marrow stromal cell differentiation into nerve cells].

The in vitro induced differentiation of mouse bone marrow stromal cells into nerve cells by retinoic acid and leukemia inhibitory factor has been shown, using morphological, histochemical and immunocytochemical analyses. The developed techniques allow to obtain up to 30% of neural cells in vitro. A suggestion about pluripotency of bone marrow stromal cells and possibility of their application to the cell therapy is discussed.

Animals↗

PubMed2001

Structure of cell clusters formed in cultures of dissociated human embryonic brain.

Cell clusters in a culture of dissociated brain from human fetuses at 8-12 weeks gestation in a serum-free growth medium were studied by immunohistochemical methods and electron microscopy. Heterogeneity of cell population in culture was demonstrated. Despite the influence of proliferation-stimulating factors, cell clusters contained not only nestin-immunopositive stem cells, but also beta-tubulin-, vimentin-, and GFAP-positive cells differentiating by the neural pathway. Stem cells were localized on the surface of clusters. The percentage of stem cells in large clusters was lower than in small clusters.

Brain↗

PubMed2001

In vitro development of neural progenitor cells from human embryos.

Behavior of stem/progenitor cells from the brain of human embryos during in vitro culturing was studied. Cultured cells from human embryonic brain developed and formed neurospheres heterogeneous by their cell composition. In a serum-containing medium some cells underwent differentiation by the neuronal pathway, while others remained in the stem state.

Cell Differentiation↗

PubMed2001

Transplantation of cultured human neural progenitor cells into rat brain: migration and differentiation.

We studied the fate in vitro cultured human stem/progenitor cells after transplantation into rat brain. The cells from human fetuses at 8-12 weeks' gestation were cultured in vitro for 14 days and transplanted into the brain of 10-day-old and adult rats. Microscopic examination showed that human stem/progenitor cells migrated into various regions of rat brain. Immunohistochemical assay demonstrated that some cells differentiated into astrocytes and neurons, while others retained the embryonic phenotype.

Animals↗

PubMed2000

[Strain-specific response in mice to the neonatal administration of ACTH(4-10) fragment: behavior, neurochemistry, and brain morphology].

Neonatal injection of the ACTH4-10 fragment (5 micrograms daily for five days) caused genotype-dependent changes in concentrations of some monoaminergic neuromediators and their metabolites in hippocampus and brain stem of adult CBA and 101/HY mice. The catecholaminergic neurons increased in number in hypothalamic zona incerta of adult 101/HY mice. Neonatal injection of the peptide caused also genotype-dependent changes in the exploratory behavior of adult animals. Sound sensitivity was reduced in the 101/HY mice, whereas no sensitivity was revealed in both control and experimental groups of the CBA mice. The effects discovered were suggested to be caused by changes in neuronal differentiation.

Acoustic Stimulation↗