A modified in vitro stripping method to automate the calculation of geometry of corneocytes imaged with fluorescent microscopy: example of moisturizer treatment

Background/purpose To develop a modification of the stripping method allowing quick automated processing of corneocyte samples to study human skin conditions. Although the previous scrubbing technique and stripping method can provide sufficient information about human corneocytes, they are either subject to artifacts or involve time-consuming data processing. Methods and Materials In the first stage, an adhesive tape is used to collect corneocytes as in the regular stripping method. Then, a D-squame skin indicator is used to divide the collected corneocytes into a lesser populated sample, in which more individual corneocytes can be observed with the help of fluorescent microscopy after dye staining. The method was applied to study the change of corneocytes after moisturizer (glycerin) treatment. Results The modified stripping method described allows the automated processing of the geometrical characteristics of corneocytes. Data for several hundreds of corneocytes can easily be collected. The analysis of glycerin treatment demonstrated a high sensitivity for the method. An average increase of the corneocyte area of 5.1% was found after 9 days of treatment (the accuracy of the method was 0.5%). Conclusion The method described is suitable for the automated data processing. It allows for the reliable detection of the expansion of the average area of corneocytes after 9 days of daily glycerin treatment.