ABSTRACT
BACKGROUND: Mesenchymal stem cells are pluripotent cells that have the ability to generate cells from a cell line or in other cell types from different tissues but from the same origin. Although those cells have more limited differentiation capacity than embryonic stem cells, they are easily obtained from somatic tissue and can be grown in large quantities. This characteristic of undifferentiated stem cells differentiating into different cell lines arouses strategies in regenerative medicine for the treatment of different diseases such as neurodegenerative diseases. AIM: To evaluate the cell differentiation capacity of human breastmilk stem cells for the three germ layers by a systematic review. METHODS: The searched databases were PubMed, EMBASE, OVID, and COCHRANE LIBRARY, published between 2007 and 2018 in the English language. All were in vitro studies for analysis of the "cell differentiation potential" in the literature using the keywords "human breastmilk," "stem cells," and keywords combined with the Boolean operator "NOT" were used to exclude those articles that had the word "CANCER" and their respective synonyms, which were previously consulted according to medical subject heading terms. PRISMA 2009 guidelines were followed in this study. RESULTS: A total of 315 titles and abstracts of articles were examined. From these, 21 were in common with more than one database, leaving 294 articles for analysis. Of that total, five publications met the inclusion criteria. When analyzing the publications, it was demonstrated that human breastmilk stem cells have a high cellular plasticity, exhibiting the ability to generate cells of all three germ layers, endoderm, mesoderm, and ectoderm, demonstrating their stemness. Those cells expressed the genes, TRA-1-60/81, octamer-binding transcription factor 4, and NANOG, of which NANOG, a critical regulator for self-renewal and maintenance, was the most highly expressed. Those cells have the ability to differentiate in vitro into adipocytes, chondrocytes, osteocytes, oligodendrocytes, astrocytes, and neurons as well hepatocytes, ß-pancreatic cells, and cardiomyocytes. CONCLUSION: Although the literature has been scarce, the pluripotentiality of these cells represents great potential for tissue engineering and cellular therapy. Further studies for safe clinical translation are needed.
ABSTRACT
O diagnóstico genético pré-implantacional (PGD) é uma ferramenta que permite a selec¸ão do embrião saudável por meio da análise gênica e cromossômica. Beneficia casais no grupo de risco, como, por exemplo, casais com histórico de aborto de repetição ou com histórico familiar de doença hereditária. Diante do avanço das metodologias empregadas no PGD, esta revisão tem como objetivo reunir as informações acerca das técnicas de biópsia, de biologia molecular e aspectos bioéticos dessa prática. Assim, foi possível agregar as informações como vantagens, desvantagens, restrições e indicações referentes ao estágio embrionário em que é retirado o material genético e as técnicas de biologia molecular usadas na análise genética. Além disso, foi possível especificar alguns questionamentos bioéticos que surgem com a prática do PGD, como, por exemplo, a possível eugenia. Concluiu-se que a análise da trofoectoderme dos embriões e da aplicação da tecnologia de NGS é promissora para o futuro do PGD, bem como a primordialidade da criação de leis que regem e completam as lacunas no sentido ético e moral dessa prática.(AU)
The preimplantation genetic diagnosis (PGD) is a tool that allows the selection of healthy embrios through gene and chromosome analysis, benefiting couples at risk. Like couples with recurrent miscarriage or family history of hereditary disease. Given the advance of the methodologies used in PGD this review aims to assemble information about the biopsy techniques, molecular biology and bioethical aspects of this practice. Therefore, it was possible collect the information like advantages, disadvantages, restrictions and indications referring to embryonic stage in which is made the removal of genetic material and molecular biology techniques used in genetic analysis. In addition, some bioethic questions that arise with the practice of PGD were verified as, for example, possible Eugenia. It was concluded that the analysis of trofoectoderme of embryos and the application of NGS technology is promising for the future of PGD, as well as the primordiality the creating laws governing and complete the gaps in the ethical and moral sense of this practice.(AU)
