Skin histopathology evaluation. A. ADSCs or fractional CO2 laser treatment improved dermal thickness in the photoaging skin induced by UVB irradiation. B. V&G staining shows the light red collagen fibers(* indicate) decreased,dyeing shallowed,especially in the superficial layer dermis,however,the dark red elastic fiber(arrows indicate) increased, thicker, partial hyperplastic elastic fibers were fractured and snarling after UVB irradiation. ×400. Scale bars are 100 μm. C. fibers were stianed red,and that improved the enlarged diameter metamorphic fizzy fibers with infiltration of inflammatory cells in ADSC transplantation group (c,d) and CO2 fractional laser treatment group (g,h). The improvement effect was significantly increased in combined treatment group (e,f). H&E × 400. Scale bars are 100 μm.