Fetal-adult phenotype transition, in terms of the serum dependency and growth factor requirements, of human skin fibroblast migration.

Since the migration of human fetal skin fibroblasts into a denuded area of a cell monolayer has been demonstrated to be serum-independent (fetal phenotype), whereas that of adult-donor skin fibroblasts is serum-dependent (adult phenotype), a study was carried out to determine at which life stage the fetal-adult phenotype transition, in terms of serum dependency of human skin fibroblast migration, occurs. The results demonstrated that this phenotype transition occurred before birth, and, therefore, the fetal skin fibroblast phenotype differed from those of infant-, child-, adult-, and elderly-donor skin fibroblasts. But, the fetal-, child-, and adult-donor skin fibroblast phenotypes did not change during in vitro aging. On the other hand, the growth factor requirement for human skin fibroblast migration changed similarly to the serum dependency for fibroblast migration: the signal for fibroblast migration changed from basic fibroblast growth factor for the fetal phenotype to platelet-derived growth factor for the adult phenotype.