Establishment of banking system for allogeneic cultured dermal substitute.

Allogeneic cultured dermal substitute (CDS) was prepared by culturing fibroblasts on a two-layered spongy matrix of hyaluronic acid (HA) and atelo-collagen (Col). Allogeneic CDS can be cryopreserved and transported to other hospitals in a frozen state. Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), platelet derived growth factor (PDGF)-AA, transforming growth factor (TGF)-beta1, keratinocytes growth factor (KGF), interleukin (IL)-6 and IL-8 were contained in the culture medium which was used in preparing CDS over a cultivation period of one week (fresh CDS culture medium sample). After thawing a cryopreserved CDS, the CDS was recultured in a culture medium for one week. VEGF, bFGF, HGF, TGF-beta1 and IL-8 were contained in the culture medium which was used in reculturing CDS for one week (cryopreserved CDS culture medium sample), although some cytokines were detected at a lower level than those before freezing. This finding suggests that the cryopreserved CDS retains its ability to release these cytokines. Clinical research on allogeneic CDS, which was newly developed at the R & D Center for Artificial Skin of Kitasato University, has been carried out in medical centers across Japan with the support of the Millennium Project of the Ministry of Health, Labor and Welfare. It was demonstrated that the allogeneic CDS functions as an excellent cell therapy for intractable skin ulcers as well as burn injuries. The spongy matrix itself, as well as the cytokines released from the allogeneic CDS, seemed to be beneficial for the treatment of intractable skin defect.