Human serum albumin as a clinically accepted cell carrier solution for skin regenerative application.

The rules governing Medicinal Products in the European Union necessitates the production of cell-based therapy in good manufacturing practice facilities. The produced cells may need several hours in transportation to reach the application sites. In this study, we investigated four candidate solutions for transporting human keratinocytes. The solutions are (1) normal saline, (2) saline with 2.5% human serum albumin (Saline + HSA), (3) chemically defined, xeno-free keratinocyte media and (4) keratinocyte media with pituitary bovine extract (PBE-media). One million keratinocytes from three donors were suspended in each solution and kept at 4 °C for up to 24 h. Cells kept in Saline + HSA showed higher viability after 1, 3 and 24 h. Then, equal number of viable cells were seeded on collagenous matrix and cultured for 48 h. The adhesion and colonization were higher in the cells kept in PBE-media, while the keratinocyte surface marker, cytokeratin 14, was present in all studied groups. These results confirmed the suitability of Saline + HSA as a cell transportation solution for clinical use, which will be the choice for the planned clinical trial. Keratinocyte PBE-media can be an alternative for cells transported for research purpose, if the same media type is going to be used in the following experiments.