Models of reconstructed sensitive skin

A process for preparing a model of reconstructed sensitive skin, comprising the steps of:

• a) obtaining a skin sample from a subject;
• b) obtaining a reconstructed skin model from the skin sample of step a);
• c) contacting the reconstructed skin model from step b) with lactic acid for at least 48h, wherein the concentration of lactic acid used is about 0.6%;
• and
• d) measuring the expression level of a combination of biological markers, said combination comprising;
• skin inflammation markers comprising IL8, IL1α, ILR1A, ω-6 polyunsaturated fatty acids, ω-9 polyunsaturated fatty acids, prostaglandin E2, PLA2G2F, MGST1, and VEGF-A,
• barrier markers comprising involucrin, and
• defense markers comprising beta-defensin 2 and Toll-like receptor 2;
• wherein:
• (i) the expression level of the skin inflammation markers is higher in the reconstructed skin model from step d) than in normal skin;
• and
• (ii) the expression level of the barrier markers is lower in the reconstructed skin model from step d) than in normal skin;
• and
• (iii) the expression level of the defense markers is lower in the reconstructed skin model from step d) than in normal skin.