Objective: To observe the differences in protein contents of three transforming growth factor-beta (TGF-beta) isoforms, beta 1, beta 2, beta 3 and their receptor(I) in hypertrophic scar and normal skin and to explore their influence on scar formation.
Methods: Eight cases of hypertrophic scar and their corresponding normal skin were detected to compare the expression and distribution of TGF-beta 1, beta 2, beta 3 and receptor(I) with immunohistochemistry and common pathological methods.
Results: Positive signals of TGF-beta 1, beta 2, and beta 3 could all be detected in normal skin, mainly in the cytoplasm and extracellular matrix of epidermal cells; in addition, those factors could also be found in interfollicular keratinocytes and sweat gland cells; and the positive particles of TGF-beta R(I) were mostly located in the membrane of keratinocytes and some fibroblasts. In hypertrophic scar, TGF-beta 1 and beta 3 could be detected in epidermal basal cells; TGF-beta 2 chiefly distributed in epidermal cells and some fibroblast cells; the protein contents of TGF-beta 1 and beta 3 were significantly lower than that of normal skin, while the change of TGF-beta 2 content was undistinguished when compared with normal skin. In two kinds of tissues, the distribution and the content of TGF-beta R(I) had no obviously difference.
Conclusion: The different expression and distribution of TGF-beta 1, beta 2 and beta 3 between hypertrophic scar and normal skin may be associated with the mechanism controlling scar formation, in which the role of the TGF-beta R (I) and downstream signal factors need to be further studied.