RESUMEN
OBJECTIVES: The first-passage adherent human bone marrow fibroblast-like cell population corresponds, in terms of phenotype and three-lineage differentiation capacity (assayed in bulk culture), to commonly termed "mesenchymal stem cells". Here we determine the proportion of high proliferative capacity multipotent cells present in this population in order to estimate the proportion of cells that can or cannot be considered as stem and progenitor cells. MATERIAL AND METHODS: The single-cell cultures were established starting from human bone marrow-derived first-passage fibroblast-like cells and the proliferating clones were either transferred to secondary cultures to evaluate their further clonogenicity, or split into three wells to assess differentiation into each of the three different lineages. RESULTS: The analysis of 197 single-cell cultures from three different bone marrow donors shows that onlyâ¼40% of so-called "mesenchymal stem cells" exhibit multipotency and are capable of sustained clonogenicity in secondary cultures. CONCLUSION: Even in the first ex vivo passage under favorable conditions the majority (â¼60%) of so-called "mesenchymal stem cells" are not multipotent and thus do not represent a stem cell entity.
Asunto(s)
Células Madre Mesenquimatosas/citología , Antígenos CD/análisis , Células de la Médula Ósea/clasificación , Adhesión Celular , División Celular , Linaje de la Célula , Autorrenovación de las Células , Separación Celular , Células Cultivadas , Células Clonales/citología , Ensayo de Unidades Formadoras de Colonias , Factor 2 de Crecimiento de Fibroblastos/farmacología , Humanos , Análisis de la Célula Individual , Células del Estroma/citologíaRESUMEN
The maintenance of the primitive Hematopoietic Stem Cells (HSC) in course of ex vivo expansion is a critical point to preserve the long-term reconstituting capacity of a hematopoietic graft. On the basis of the numerous experimental results, the maintenance of primitive HSC is related to their specific metabolic profile shifted towards the anaerobiosis. Hence, in addition to the exposition of the cultures to more appropriate, physiologically low O2 concentrations (usually misleadingly termed "hypoxia"), a specter of "hypoxia-mimicking" factors (cytokines, growth factors, receptor-ligands, antioxidants) can be applied to maintain this specific metabolic profile enabling an appropriate genetic and epigenetic regulation. Some factors already proved to be able to achieve this goal and "hypoxia-mimicking" ex vivo cultures were already used to produce cells for clinical trials. In this article we are discussing the approaches aimed to amplify and/or to condition the HSC, based on the manipulation of energetic metabolism properties.
Asunto(s)
Metabolismo Energético , Células Madre Hematopoyéticas/metabolismo , Anaerobiosis , Hipoxia de la Célula , Autorrenovación de las Células , Células Cultivadas , Medios de Cultivo/farmacología , Citocinas/farmacología , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Mitocondrias/fisiología , Fosforilación Oxidativa , Oxígeno/metabolismo , Oxígeno/farmacología , Especies Reactivas de Oxígeno/metabolismo , Transducción de SeñalRESUMEN
AIMS: The potential use of bifidobacteria as indicators for faecal contamination was studied along a sheep meat production and processing chain. The levels of bifidobacteria were compared with those of Escherichia coli. Total viable counts were followed along the chain (244 samples). METHODS AND RESULTS: Forty-three per cent of the samples contained bifidobacteria, of which 15% were solely detected using a PCR method based on the hsp60 gene and not by a culture-based method. Bifidobacteria were detected in only three of nine sheep faeces samples using one or the other method. However, carcasses (types C and E) were highly contaminated. These sample types (30% and 28%, respectively) were positive for bifidobacteria and negative for E. coli. The species Bifidobacterium pseudolongum and Bif. thermophilum, isolated from faecal samples, were predominant. Bifidobacterium choerinum were found in C, D, E and F sample types. CONCLUSIONS: Bifidobacteria were shown more efficient than E. coli in carcasses samples. The presence of Bif. choerinum suggested a faecal pork contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: Detection and identification of bifidobacteria, in correlation with E. coli counting, should improve hygiene quality of mutton processing chains.
Asunto(s)
Bifidobacterium/aislamiento & purificación , Heces/microbiología , Microbiología de Alimentos , Carne/microbiología , Mataderos , Animales , Técnicas Bacteriológicas , Bifidobacterium/genética , Chaperonina 60/genética , Recuento de Colonia Microbiana , Escherichia coli/aislamiento & purificación , Inspección de Alimentos/métodos , Industria de Procesamiento de Alimentos , Humanos , Productos de la Carne/microbiología , Reacción en Cadena de la Polimerasa/métodos , OvinosRESUMEN
A female patient with coexistence of pemphigus herpetiformis and systemic lupus erythematosus is described. She presented to our Department with pruritic vesicles on her trunk and extremities, which were later accompanied with butterfly like erythema on her face and with central nervous system (CNS) manifestations. The diagnosis of pemphigus herpetiformis was based on the clinical picture and immunofluorescence finding, because the histopathologic finding is not always typical for the diagnosis. The diagnosis of systemic lupus erythematosus was based on positive ANA and anti-dsDNA, presence of butterfly-like erythema on her face, and CNS manifestations. The patient was treated by corticosteroids in combination with immunosuppressants, which should ensure good control of both diseases. The coexistence of pemphigus herpetiformis and systemic lupus erythematosus has not been reported in recent literature.
