Publications by authors named "Riikka S Lappalainen"

Background: Human embryonic stem cells (hESCs) can differentiate into any human cell type, including CNS cells, and thus have high potential in regenerative medicine. Several protocols exist for neuronal differentiation of hESCs, which do not necessarily work for all hESC lines.

Materials & Methods: We tested the differentiation capacity of four similarly derived and cultured hESC lines (HS181, HS360, HS362 and HS401) in suspension culture in relatively simple neural differentiation medium for up to 20 weeks.

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Background: The growth of stem cells in in vitro conditions requires optimal balance between signals mediating cell survival, proliferation, and self-renewal. For clinical application of stem cells, the use of completely defined conditions and elimination of all animal-derived materials from the establishment, culture, and differentiation processes is desirable.

Methodology/principal Findings: Here, we report the development of a fully defined xeno-free medium (RegES), capable of supporting the expansion of human embryonic stem cells (hESC), induced pluripotent stem cells (iPSC) and adipose stem cells (ASC).

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Background: Glutamate metabolism is associated with myocardial ischemia-reperfusion, but it is not clear whether glutamate reveals ongoing ischemia (OI). We evaluated whether microdialysis would detect OI induced by coronary artery ligation in a rat cardiac transplantation model.

Material And Methods: A total of 24 Fischer 344 rats underwent syngeneic heterotopic cardiac transplantation.

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An optimal surface for culturing human embryonic stem cell (hESC)-derived neuronal cells is of high interest. In this study, a specific antibody to a neural cell adhesion molecule (NCAM) was immobilised on a solid surface of polystyrene and used as a selective matrix for culturing of hESC-derived neuronal cells. Thereafter, hESC-derived neurospheres were seeded on the matrix.

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The production of functional human embryonic stem cell (hESC)-derived neuronal cells is critical for the application of hESCs in treating neurodegenerative disorders. To study the potential functionality of hESC-derived neurons, we cultured and monitored the development of hESC-derived neuronal networks on microelectrode arrays. Immunocytochemical studies revealed that these networks were positive for the neuronal marker proteins beta-tubulin(III) and microtubule-associated protein 2 (MAP-2).

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Cortical stem cell transplantation may help replace lost brain cells after stroke and improve the functional outcome. In this study, we transplanted human embryonic stem cell (hESC)-derived neural precursor cells (hNPCs) or vehicle into the cortex of rats after permanent distal middle cerebral artery occlusion (dMCAO) or sham-operation, and followed functional recovery in the cylinder and staircase tests. The hNPCs were examined prior to transplantation, and they expressed neuroectodermal markers but not markers for undifferentiated hESCs or non-neural cells.

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The regenerative potential of stem cells from various sources has been under intense investigation in the experimental models of cerebral ischemia. To end up with a restorative therapeutic treatment, it is crucial to get the cell transplants to the site of injury. Here, we evaluated the feasibility of small animal SPECT/CT in assessing the definite accumulation of (111)In-oxine-labeled human embryonic stem (ES) cell-derived neural progenitors and rat hippocampal progenitors after intravenous or intra-arterial administration (femoral vein vs.

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