Elastin-derived peptides (kappa-elastin: kappa E, mean molecular mass: 75 kDa), either coated onto plastic dishes or added to culture media (0.26 to 1.33 nM) stimulated the growth of human skin fibroblasts (HSF) strains obtained from different donors and tested at different cell passages (4 to 12). Coated 44.4 micrograms/cm2 insoluble elastin (iE) exhibited the same action; coated iE or kappa E significantly modifies the HSF morphology: after 5-6 days of culture, HSF are more elongated, and at preconfluence state, formation of HSF clusters surrounding iE were observed. Increased 3H thymidine incorporation and proliferative effect of HSF by kappa E (1.3 to 2.2 fold as compared to control cells) was observed after a lag phase period which raised with initial HSF density. Optimal proliferative effect was obtained at kappa E 8.5 10(-10) M, a value close to the dissociation constant (kD = 2.7 10(-10) M) of kappa E to HSF. Valine-glycine-valine-alanine-proline-glycine (VGVAPG), but not valine-glycine-valine (VGV) or Valine-glycine-valine-valine-glycine-alanine (VGVVGA) also significantly stimulated, optimally at 7.0 10(-10) M, HSF proliferation. It was concluded that the stimulatory influence of elastin derived peptides on HSF proliferation was mediated through a binding to plasmalemmal receptor of HSF.