Loss of factor XIIIa in pig dermis during tissue expansion

Considerable evidence suggests that factor XIIIa, a blood coagulation factor, also functions in tissue repair, and specifically in the dynamic process of fibroplasia. On the other hand, the dynamic process of tissue expansion would require a loosening of the dermis, the opposite of fibroplasia. We examined the effects of tissue expansion on the expression of factor XIIIa in pig skin. Standard immunohistochemical procedures were used coupled with a rabbit antibody to factor XIIIa. In this report, we demonstrate that the normal expression of factor XIIIa in pig dermis is completely inhibited at the apex overlying the tissue expander. Factor XIIIa inhibition during expansion supports the thesis that this substance is important in the production and maintenance of fibroplasia.