Application of methods for viral clearance in stem cell production.

Regenerative medicine therapies will allow in the future the transplant of cells of human origin in some diseases that until now have been incurable. The assurance of the safety and quality, especially from a microbiological point of view, is very important for these therapeutic products. Depending on the starting material, there are several sources of pathogen presence, mainly human viruses. Also, the use of feeders of animal origin as layers in which the stem cells can grow may permit the transmission of animal pathogens to these cells. However, cell sources are limited due to the low availability of spare in vitro fecundation human embryos and the low rate of success in the derivation of human stem cell lines. Thus, in several cases, it will be necessary to evaluate the possibility of removing or inactivating these microorganisms. In this paper, we summarize the main methods of viral clearance and we have provided an overview of the main features taking into account in the viral clearance techniques.