Multi parameter flow cytometric assessment of regenerative epidermis with special reference to the antiproliferative effect of occlusion

Multi parameter Row cytometrical assays permit simultaneous assessment of p roliferation, differentiation, and inflammation parameters. In this study, the validation of TO-PRO-3 iodide (TP3) compared to propidium iodide (PI) a nd DE-K10 compared to RKSE60 were evaluated in tape stripping induced hyper proliferation. No occlusion, Duoderm (intermediate occlusion) and Blenderm (maximal occlusion) were used as a model to evaluate the effect of occlusio n on epidermal regeneration. Proliferation in the keratin 10-negative compa rtment measured with TP3 proved to be a good approximation of proliferation measured with PI. Other epidermal subpopulations (keratin 10-dim and -brig ht cells) did not make a relevant contribution to hyperproliferation. DE-K1 0 is probable more sensitive than RKSE60 to distinguish populations that di ffer in degree of differentiation. Occlusion of tape stripped skin resulted in decreased proliferation and increased differentiation. This effect was most pronounced with maximal occlusion. This study showed that occlusion is a therapy, which realises normalisation of hyperproliferative skin disorde rs.