RESUMO
With the introduction of regenerative medicine and cell therapy programmes by means of human embryonic stem cells (hESC), several research centres have begun projects of derivation of hESC lines. In some stem cell banks, such as the Andalusian Stem Cell Bank, the law also permits the creation of these cell lines. Therefore, the recovery of cryopreserved embryos, their culture and the subsequent derivation to hESC lines requires a suitable embryology laboratory and specialized and highly qualified staff. Moreover, new techniques, from therapeutic nuclear transfer, need this type of laboratory and staff, too. Several International Associations have drawn up some guidelines for laboratories where embryos are manipulated and they reflect the physical space, the staff and the equipment needed in these kinds of laboratories. Nevertheless, we can see that these guidelines do not distinguish between IVF laboratories and other laboratories that obtain hESC lines, so it would be convenient to make a distinction. Following these guidelines, we have tried to draw up concurrent aspects applicable to areas of embryology within stem cell banks. So, the design and the specific implementation programmes for these areas and other research centres with this area but which do not use IVF techniques is vital to develop embryonic cell lines in optimum conditions for future therapeutic applications, although maybe it is rather premature to standardize this type of research.
RESUMO
The transplant of cells of human origin is an increasingly complex sector of medicine which entails great opportunities for the treatment of a range of diseases. Stem cell banks should assure the quality, traceability and safety of cultures for transplantation and must implement an effective programme to prevent contamination of the final product. In donors, the presence of infectious micro-organisms, like human immunodeficiency virus, hepatitis B virus, hepatitis C virus and human T cell lymphotrophic virus, should be evaluated in addition to the possibility of other new infectious agents (e.g. transmissible spongiform encephalopathies and severe acute respiratory syndrome). The introduction of the nucleic acid amplification can avoid the window period of these viral infections. Contamination from the laboratory environment can be achieved by routine screening for bacteria, fungi, yeast and mycoplasma by European pharmacopoeia tests. Fastidious micro-organisms, and an adventitious or endogenous virus, is a well-known fact that will also have to be considered for processes involving in vitro culture of stem cells. It is also a standard part of current good practice in stem cell banks to carry out routine environmental microbiological monitoring of the cleanrooms where the cell cultures and their products are prepared. The risk of viral contamination from products of animal origin, like bovine serum and mouse fibroblasts as a "feeder layer" for the development of embryonic cell lines, should also be considered. Stem cell lines should be tested for prion particles and a virus of animal origin that assure an acceptable quality.