Progres microscope camera

Frozen sections of dorsal skin tissues were embedded in the Optimal Cutting Temperature compound (Bright Cryo-M-Bed; Bright Instruments, Luton, United Kingdom) and were stored at −80°C for further processing. Next, 10 µm of frozen skin samples were sectioned with a cryostat (CM1520; Leica Microsystems, Wetzlar, Germany). Then, skin sections were stained with hematoxylin and eosin (H&E) following standard protocols. Sections were imaged and captured with the ProGres Microscope Camera (Jenoptik, Jena, Germany) with exposure settings of 1.5 ms, light at 7.0, and magnification at ×10. Epidermal thickness (µm) was quantified with ImageJ software (v.1.32; National Institutes of Health, Bethesda, MD, USA) and was measured between the epidermal surface and the epidermal–dermal junction, excluding the rete ridges. The average thickness was determined over an average of 6–10 sections/animal. For each skin section, we measured the whole length of the skin where possible (hence, at ×10 magnification, they were determined by ≥3–4 images). For each image, we took 8 points distributed evenly over the epidermis and averaged them. Hence, the data presented here is the value of average epidermal thickness/percentage of area coverage.