The role of fetal-maternal microchimerism as a natural-born healer in integrity improvement of maternal damaged kidney

ABSTRACT Purpose: To identify the fetal stem cell (FSC) response to maternal renal injury with emphasis on renal integrity improvement and Y chromosome detection in damaged maternal kidney. Materials and Methods: Eight non-green fluorescent protein (GFP) transgenic Sprague-Dawley rats were mated with GFP-positive transgenic male rats. Renal damage was induced on the right kidney at gestational day 11. The same procedure was performed in eight non-pregnant rats as control group. Three months after delivery, right ne- phrectomy was performed in order to evaluate the injured kidney. The fresh perfused kidneys were stained with anti-GFP antibody. Polymerase chain reaction (PCR) assay was also performed for the Y chromosome detection. Cell culture was performed to detect the GFP-positive cells. Technetium-99m-DMSA renal scan and single-photon emission computed tomography (SPECT) were performed after renal damage induction and 3 months later to evaluate the improvement of renal integrity. Results: The presence of FSCs was confirmed by immune histochemical staining as well as immunofluorescent imaging of the damaged part. Gradient PCR of female rat purified DNA demonstrated the presence of Y-chromosome in the damaged maternal kidney. Moreover, the culture of kidney cells showed GPF- positive cells by immuno- fluorescence microscopy. The acute renal scar was repaired and the integrity of dam- aged kidney reached to near normal levels in experimental group as shown in DMSA scan. However, no significant improvement was observed in control group. Conclusion: FSC seems to be the main mechanism in repairing of the maternal renal injury during pregnancy as indicated by Y chromosome and GFP-positive cells in the sub-cultured medium.

O intervalo de tempo entre coleta e processamento do sangue de cordão umbilical influencia na qualidade da amostra? / Does the time between collecting and processing umbilical cord bloodsamples affect the quality of the sample?

Objective: To assess the association between the time from umbilical cord blood collection until processing and the quality of the sample. Methods: Umbilical cord blood samples collected during the third stage of labor were placed in temperature-controlled boxes for the transport of biological material and sent to an umbilical cord blood bank, where the number of nucleated cells, viable cells and CD34+ cells were counted, and samples were additionally tested for contamination at the following time intervals: up to 24 hours, up to 48 hours and up to 72 hours following sampling. Data were analyzed using the multivariate analysis of variance (MANOVA) and compared using McNemar's X2 test. Significance was defined at p < 0.05. Results: Means and medians of the number of nucleated cells, viable cells and CD34+ cells decreased significantly (p < 0.0001) as a function of the increased time between sampling and analysis, the difference between 24 and 48 hours being less than the difference between 24 and 72 hours. A linear correlation was found between the mean number of viable cells and CD34+ cells at the three moments of analysis. Contamination testing was negative in all samples. Conclusion: The increase in time interval from sampling until analysis negatively affected the number of nucleated cells, viable cells and CD34+ cells but was not associated with specimen contamination. A linear correlation was found between decrease in the number of viable cells and CD34+ cells.

Objetivo: Avaliar a associação do intervalo de tempo entre coleta e processamento do sangue de cordão umbilical e a qualidade da amostra. Métodos: As amostras de sangue de cordão umbilical, colhidas no terceiro período do parto, foram acondicionadas em caixas homologadas para transporte de material biológico, com monitoração da temperatura, e enviadas a um banco de sangue de cordão umbilical, onde foram submetidas à contagem do número de células nucleadas, do número de células viáveis, do número de células CD 34+ e pesquisa de contaminação, nos intervalos de tempo de até 24, até 48 e até 72 horas. Os dados foram analisados pelo teste de variância para medidas repetidas MANOVA e comparados por meio do teste do X2 de Mc Nemar, considerando-se nível de significância de 5%. Resultados: As médias e as medianas do número de células nucleadas, número de células viáveis e número de células CD34+ tiveram quedas significativas (p < 0,0001) com o aumento do intervalo de tempo de coleta/processamento, sendo entre 24 e 48 horas menor do que a comparação entre 24 e 72 horas. Constatada correlação linear entre as médias de células viáveis e células CD34+ nos três momentos da análise. A pesquisa de contaminação foi negativa em todas as amostras. Conclusão: O aumento do intervalo de tempo de coleta/processamento influenciou negativamente na contagem de células nucleadas, células viáveis e CD34+ e não esteve associado à contaminação das amostras. Foi constatada correlação linear entre a queda do número de células viáveis e de células CD34+.

Consideraciones científicas y éticas en las perspectivas diagnósticas y terapéuticas en medicina fetal / Scientific and ethical perspectives of perinatal and fetal medicine

This review emphasizes the importance of recent developments and knowledge on cell biology and human genetics than have integrated, through a basic-clinical concept to an emerging branch of medicine, called Perinatal and Fetal Medicine. We discuss the possible role of fetal cells and DNA in the diagnosis and treatment of diseases in the intrauterine environment. The associated bioethical issues associated to these medical actions are discussed, considering the imminent use ofthese agents in the human species.

Hallazgos histológicoultraestructurales característicos de las células madres (stem cell embriónico fetales): primer reporte internacional / Ultra structural histologic findings characteristic of embryonic fetal stem cells: first international report

Se buscó la evidencia de crecimiento muscular o biogénesis que debería haberse iniciado a partir del transplante de Stem cell embriónico fetales de donantes con el propósito de observar los dos tipos de ADN distintos tanto del receptor como del donante. Materiales y métodos: esta investigación se realizó luego de recibir fragmentos de músculo cardiaco del ventrículo izquierdo en los cuales se implantaron dichas células directamente en el miocardio mediante 80 inyecciones de 1ml cada una en todas las paredes de ambos ventrículos, con especial énfasis en el izquierdo. Las biopsias fueron fijadas con glutaraldehido al 3, post-fijazas con Tetraóxido de Osmio al 1, deshidratadas en diversos gradientes ascendentes de alcohol etílico, preembedidas en Oxido de propileno, embebidas en resina Spurr para realizar los bloques, los cuales fueron cortados por ultramicrotomía, teñidas con acetato de uranilo y citrato de plomo, y finalmente observadas al Microscopio Electrónico de Transmisión JEOL- JEM 1010. Resultados: lo más relevante en esta investigación son los hallazgos encontrados en las mitocondrias que se presentaban hipertróficas, redondeadas con crestas vesiculares, siendo lo distintivo y el más importante hallazgo la presencia de una banda recta trilaminar con una estructura central electrondensa proteica, la misma que atraviesa perpendicularmente en toda la longitud de la mitocondria, formando una “Barra germinativa pluripotencial mitocondrial”, hallazgo propio distintivo de las células Madre. Conclusiones: siendo en la mitocondria esta inusual barra recta transversal electrondensa un importante aporte científico distintivo que identificaría plenamente a las células transplantadas del tipo de Stem cell embriónico fetales, diferentes a las mitocondrias con crestas cortas irregulares onduladas paralelas vacías, dando con esto una diferenciación característica que determinaría su capacidad de ser pluripotencial y de autorenovación.

We looked up an evidence of muscle growth or biogenesis that should have started from the transplant of embryonic fetal stem cells from donors in order to observe the two distinct AND types of both, the receptor and the donor. Materials and methods: this research was made after receiving fragments of the left ventricle cardiac muscle where those cells were implanted directly in the myocardio by means of 80 injections of 1 ml each in all the walls of both ventricles, with special stress in the left one. Biopsies were fixed with 3 glutaraldehido, post fixed with 1 Osmio Tetraoxide, dehydrated in different ascending gradients of ethyl alcohol, pre soaked in propylene oxide, soaked in Spurr resin to make the blocks which were cut by ultramicrotomy, dyed with uramil acetate and lead citrate, and finally observed at the JEOL – JEM 1010 Transmission Electronic Microscope. Results: the most outstanding facts in this research are the findings met in the mitochondrion that were hypertrophic, rounded with vesicular crests, and what makes difference and the most important finding is the presence of a tri-laminar straight strip with a central proteinic electrodense structure which crosses perpendicularly the mitochondrion in its whole length, giving form to a “Mitochondrial pluripotential germinative Bar” distinctive finding of stem cells. Conclusions: this unusual electrodense, transverse, straight bar is an important scientific contribution and a distinctive that would identify completely the transplanted stem cells embryonic fetal type, different from mitochondrion with short irregular wavy, parallel, empty crests, giving this way a characteristic differentiation that would determine their capability of being pluripotential and with self-renovation.

Regeneration of kidney tissue using in vitro cultured fetal kidney cells

Transplanting fetal kidney cells (FKCs) can regenerate kidney. This requires in vitro expansion in cell number to acquire enough cells for transplantation. However, FKCs may change their cellular characteristics during expansion and, thus, may not regenerate kidney tissue upon transplantation. We investigated how cell culture period affects cellular characteristics and in vivo regenerative potential of FKCs. As the passage number increased, cell growth rate and colony forming ability decreased while senescence and apoptosis increased. To examine in vivo regenerative potential, FKCs cultured through different numbers of passages were implanted into the parenchyma of kidneys of immunodeficient mice using fibrin gel for 4 wk. Histological analyses showed passage-dependent kidney tissue regeneration, and the regeneration was better when cells from lower number of passages were implanted. This result shows that in vitro culture of FKCs significantly affects the cell characteristics and in vivo tissue regenerative potential.