[Mixed keratinocyte culture and its composite skin graft]

We overlaid sheets of autogenous, allogeneic or mixed keratinocyte culture on allogeneic dermis to form 3 types of composite skin to cover full-thickness skin wounds, and observed their rates of survival. Both the autogenous and mixed keratinocytes culture took well, and no signs of rejection were observed. Their morphology and function appeared the same as normal skin. Cultured allogeneic keratinocyte sheets showed lower survival rate than the autogenous and mixed sheets, and they were rejected in two weeks. By examining the sex chromosome of mixed keratinocytes sheets, which have been grafted for 14 or 21 days, it was found that the allogeneic keratinocytes were progressively replaced by autogenous keratinocytes. From the above results, we think that the advantages of using mixed keratinocytes culture are that it took shorter time to obtain a clinically useful cell sheet, and it takes well without obvious rejection. We believe that it can be used to cover permanently large burn wounds.