FLG and Alzheimer disease: The HaCaT FLG sh cell line was used as a model of atopic skin as theexpression level of filaggrin in AD patients is significantly reduced.11 According to the MTT assay results, the cytotoxicityof HaCaT cells with both normal and aberrant FLG expressionwas negligible as the viability of both cell groups was in the rangeof 83–105% compared to that of untreated cells.