Fig. 4. Numbers of macrophages, neutrophils and TNF--positive cells in wounds of Smad3^-/- mice are not affected by castration. Day 3 wound sections were analysed immunohistochemically to quantify inflammatory cells, and IL-6- and TNF--immunoreactive cell numbers. (A) Numbers of macrophages were significantly reduced in day-3-wounds of castrated wild-type mice but were not affected in day-3-wounds of Smad3^-/- animals (n=4-5 per treatment group). (B) The population of neutrophils was similarly depleted in wounds of castrated wild-type mice but not of Smad3^-/- animals. (C) Numbers of TNF--positive cells were decreased in day-3-wounds of castrated wild-type animals but were not affected in day-3-wounds of castrated Smad3^-/- mice. (D) Numbers of TGF-ß1-immunoreactive inflammatory cells were increased solely in wounds of castrated wild-type mice. Arrows indicate immunoreactive cells; dashed lines in D indicate the dermal-epidermal boundary. Bars, 20 µm. Data represent mean ± s.d. ^*P<0.05; ^**P<0.01. EP, epidermis.