Células tronco não funcionam no coração

Artigo recente no Science Translational Medicine (Challenges in Using Stem Cells for Cardiac Repair; doi 10.1126/scitranslmed.3000558) com participação do pesquisador brasileiro Jose Krieger (do Incor) indica que os experimentos têm chegado a resultados pouco promissores. Eles dizem que os resultados clínicos de longo prazo são desapontadores.

Veja o resumo:

“Of the many diseases discussed in the context of stem cell therapy, those concerning the heart account for almost one-third of the publications in the field. However, the long-term clinical outcomes have been disappointing, in part because of preclinical studies failing to optimize the timing, number, type, and method of cell delivery and to account for shape changes that the heart undergoes during failure. In situations in which cardiomyocytes have been used in cell therapy, their alignment and integration with host tissue have not been realized. Here we review the present status of direct delivery of stem cells or their derivative cardiomyocytes to the heart and the particular challenges each cell type brings, and consider where we should go from here.”

Após apontar várias possíveis causas para os problemas enfrentados, os autores mostram que não perderam a esperança:

“Adult stem cells appear to be preferable in terms of safety and potential to be autologous, even if they do not form cardiomyocytes. The focus should be on identifying the mechanisms of any improvement, however small, and finding the best cell type, number, and timing of delivery to optimize that process.”

 Na frase O foco deve ser a identificação de mecanismos de alguma melhora, ainda que modesta... esta última expressão parece indicar que o entusiasmo não é grande no campo.

Mummery, C., Davis, R., & Krieger, J. (2010). Challenges in Using Stem Cells for Cardiac Repair Science Translational Medicine, 2 (27), 27-27 DOI: 10.1126/scitranslmed.3000558