PURPOSE: In some human fetuses undergoing prenatal spina bifida repair, the skin defect is too large for primary closure. The aim of this study was to engineer an autologous fetal skin analogue suitable for in utero skin reconstruction during spina bifida repair.
METHODS: Keratinocytes (KC) and fibroblasts (FB) isolated from skin biopsies of 90-day-old sheep fetuses were cultured. Thereafter, plastically compressed collagen hydrogels and fibrin gels containing FB were prepared. KC were seeded onto these dermal constructs and allowed to proliferate using different culture media. Constructs were analyzed histologically and by immunohistochemistry and compared to normal ovine fetal skin.
RESULTS: Development of a stratified epidermis covering the entire surface of the collagen gel was observed. The number of KC layers and degree of organization was dependent on the cell culture media used. The collagen hydrogels exhibited a strong tendency to shrink after eight to ten days of culture in vitro. On fibrin gels, we did not observe the formation of a physiologically organized epidermis.
CONCLUSION: Collagen-gel-based ovine fetal cell-derived skin analogues with near normal anatomy can be engineered in vitro and may be suitable for autologous fetal transplantation.