We evaluated the in situ expression of adhesion molecules (
E-selectin and
vascular cell-adhesion molecule) and proinflammatory/fibrogenic
cytokines (IL-1beta,
TNF-alpha, TGF-beta1, and PDGF) in sections of normal skin,
hypertrophic scar, and
hypertrophic scar previously treated with an irradiated mixture of
collagen-polyvinylpyrrolidone and completely resolved. Expression of these
proteins was detected by indirect immunoperoxidase staining. The
hypertrophic scar group displayed an increased amount of IL-1beta,
TNF-alpha,
TGF-beta1, and PDGF compared with the normal skin and treated
scar groups. Values were statistically significant when
cytokines in
hypertrophic scar and hypertrophic treated sections were compared. Surprisingly, no differences were detected between normal skin and treated
scars. On the other hand, differences in levels of
E-selectin and
vascular cell-adhesion molecule were not statistically significant between the groups, except for
vascular cell-adhesion molecule, which decreased in treated
scars. Also, supernatants from fibroblast cultures derived from treated
hypertrophic scar, showed a reduction in
TGF-beta1 and PDGF expression, although apparently
collagen synthesis was not affected. Based on previous data from clinical studies in human dermal
fibrosis remodeling, and the results presented here, we suggest that
collagen-polyvinylpyrrolidone modulates extracellular matrix turnover, mainly of
collagen, because expression levels of IL-1beta,
TNF-alpha,
TGF-beta1, and PDGF were diminished. We infer that
collagen-polyvinylpyrrolidone participation could also modify the inflammatory process observed in hypertrophic
scarring, by diminishing the expression of adhesion molecules, as a consequence of lower levels of proinflammatory
cytokines, mainly IL-1beta and
TNF-alpha.