In continuation of former investigations on proinflammatory
cytokines, in the present study the relevance of the
transforming growth factors TGF-alpha and
TGF-beta1 was evaluated for the diagnosis of vitality and
wound age.
Paraffin sections from human skin
wounds due to sharp force influence, which had been collected in operations and autopsies, were investigated using immunohistochemistry. The
wound age varied from a few minutes to a maximum of 6 weeks with focus on the early post-traumatic interval up to 5h. Samples from uninjured skin were available as controls.
TGF-alpha (n=74) was weakly expressed in normal skin and showed a marked increase in epidermal reactivity after a
wound age of approximately 10 min. The maximum was between 30 and 60 min.
TGF-beta1 (n=51) revealed constitutional expression only in connective tissue. An increase of immunohistochemical reaction was partially detected even in classical
stab wounds (
wound age of several minutes). The immunohistochemically detectable signal concerned--presumably due to an infiltration with
TGF-beta-rich thrombocytes--large parts of the traumatized skin and also the epidermal layers (cellular and interstitial marking).
TGF-beta1 peaked after a post-traumatic interval of 30-60 min. Both factors, especially
TGF-beta1, remained detectable in elevated levels also in older
wounds with an age of days to weeks (network in granulation tissue).
TGF-alpha and
TGF-beta1 can efficiently contribute to the estimation of vitality and
wound age based on the evaluation of
cytokine patterns. In particular, this applies to
TGF-beta1 because of its easier evaluation and rapid up-regulation. Similar to other
cytokines, the parallel investigation of control skin from the same individual must be recommended to eliminate variation in the basal expression.