Stem cells: sources and therapies

Abstract

The historical, lexical and conceptual issues embedded in stem cell biology are reviewed from technical, ethical, philosophical, judicial, clinical, economic and biopolitical perspectives. The mechanisms assigning the simultaneous capacity to self-renew and to differentiate to stem cells (immortal template DNA and asymmetric division) are evaluated in the light of the niche hypothesis for the stemness state. The induction of cell pluripotency and the different stem cells sources are presented (embryonic, adult and cord blood). We highlight the embryonic and adult stem cell properties and possible therapies while we emphasize the particular scientific and social values of cord blood donation to set up cord blood banks. The current scientific and legal frameworks of cord blood banks are reviewed at an international level as well as allogenic, dedicated and autologous donations. The expectations and the challenges in relation to present-day targeted diseases like diabetes mellitus type I, Parkinson's disease and myocardial infarction are evaluated in the light of the cellular therapies for regenerative medicine.

Evidence for Bone Marrow Adult Stem Cell Plasticity: Properties, Molecular Mechanisms, Negative Aspects, and Clinical Applications of Hematopoietic and Mesenchymal Stem Cells Transdifferentiation

“…It was learned that one umbilical cord contains an adequate number of HSCs for a successful engraftment only in low body weight patients (up to 40 kg) to reconstitute their immune system. The total number of cells, comprising hematopoietic progenitors, collected from one umbilical cord is significantly lower (roughly 5 × 10 6 ) than from BMSCs or from PB after BMSCs mobilization (roughly 1 × 10 8 ) [85]. Furthermore obese patients can be treated by BM transplants, as multiple units of cord blood are required [85].…”

“…The total number of cells, comprising hematopoietic progenitors, collected from one umbilical cord is significantly lower (roughly 5 × 10 6 ) than from BMSCs or from PB after BMSCs mobilization (roughly 1 × 10 8 ) [85]. Furthermore obese patients can be treated by BM transplants, as multiple units of cord blood are required [85]. BMSCs and BMSCs mobilized into the PB show also some disadvantages: they are mostly nondividing cells and have, respectively, 3 times and 6 times less repopulating cells than CBHSCs [85].…”

Estado actual de la terapia con células madre en el tratamiento de las cardiopatías: An update

“…Se encuentran en prácticamente todo órgano de los organismos multicelulares, independiente de su tasa de recambio celular en condiciones fisiológicas, confinadas en microambientes o nichos que regulan su actividad 4,13 . Si bien se presume que las células multipotenciales tendrían función y diferenciación tejido específica, evidencias recientes sugieren que bajo ciertas condiciones pueden reprogramarse y diferenciarse a células de otros tejidos, capacidad conocida como plasticidad o transdiferenciación celular 13,14 .…”

“…Estas células poseen la capacidad de diferenciarse hacia otros tipos celulares maduros, sugiriendo la posibilidad de regenerar, reparar o sustituir el tejido dañado con el objetivo de restaurar su función 4 . La posibilidad de favorecer la regeneración miocárdica mediante la administración de células del mismo paciente (autólogas) u otro individuo (alogénicas) representa una interesante oportunidad para reemplazar el tejido miocárdico necrótico y favorecer la limitada reparación endó-gena del corazón.…”

Stem cell therapy in intracerebral hemorrhage rat model

“…As they can be found in adult tissues, they are sometimes referred as "adult stem cells". This term, however, is misleading and should be avoided, once the embryo starts containing somatic stem cells shortly after implantation [80] . Mesenchymal stem cells (MSCs) are somatic stem cells present in virtually all organs [81] .…”