Abstract: Objective To investigate the expression and localization of platelet-derived growth factor receptor-αand-β(PDGFR-αand-β)in keloid tissues and keloid-derived fibroblasts and to explore the role of PDGFR in the pathogenesis of keloid.Methods The distribution of PDGFR was determined by immunohistochemistry technique in15keloid lesions and 10 normal skin tissues.The expression of PDGFR protein in vitro was identified by Western blotting analysis.Results Strong staining of PDGFR-βwas located in keloid tissue.However,the expression of PDGFR-αin keloid tissue seemed to be related to the status of clinical proliferation.Strong expression of PDGFR-α was observed in the lesions with a congestive and invasive margin,whereas mild expression of PDDFR-α was found in lesions with a stable margin.Expression of PDGFR-αprotein was more abundant than that of PDGFR-β protein in fibroblasts in vitro.Conclusion The elevated levels of both types of PDGFR might facilitate their responses to PDGF in keloid fibroblasts,which seems to play an important role in the formation of keloid.

Key words: Keloid, Receptors,platelet-derived growth factor, Fibroblasts