Keloid scars are benign fibroproliferative growths that respond poorly to treatment. This study sought to determine the efficacy of three different glucocorticoids (triamcinolone, methylprednisolone and dexamethasone) in altering human keloid scar tissue implanted in athymic mice. Keloid tissue obtained from three patients (one man and two women) who sought cosmetic removal of their scars was implanted into athymic mice for a duration of 15 or 30 days. The keloid tissue was examined histopathologically and evaluated by a dermatopathologist who was blinded to sample identity and who was using predetermined qualitative scoring criteria. The appearance of central calcification, granulation tissue, foreign body granulomatous reaction and acute inflammatory reaction complicated the comparison of the keloid tissue samples. However, on the basis of observations reported in the present paper, it appears that triamcinolone should remain the treatment of choice for keloid scars. The athymic mouse model that is used for studying keloid scars is the best available approach to in vivo studies; however, limitations identified in this study confound the interpretation of experimental data. Ideally, promising and novel therapies should be investigated clinically.
Probing the renin active site by collisional quenching of endogenous fluorescence.
