“only MCI/MI reduced NMF levels significantly… only MCI/MI caused remarkable changes at the microscopic level” to corneocytes (resident skin cells)…The altered corneocyte morphology suggests that skin barrier damage plays a role in the pathogenesis of MCI/MI contact allergy.”
Koppes SA1,2, Ljubojević Hadžavdić S3, Jakasa I4, Franceschi N5, Riethmüller C6, Jurakić Tončic R3, Marinovic B3, Raj N7, Rawlings AV7, Voegeli R8, Lane ME7, Haftek M9, Frings-Dresen MH1, Rustemeyer T2, Kezic S1. Effect of allergens and irritants on levels of natural moisturizing factor and corneocyte morphology. Contact Dermatitis. 2017 Mar 14. doi: 10.1111/cod.12770.
The irritant sodium lauryl sulfate (SLS) is known to cause a decrease in the stratum corneum level of natural moisturizing factor (NMF), which in itself is associated with changes in corneocyte surface topography.
To explore this phenomenon in allergic contact dermatitis.
Patch testing was performed on patients with previously positive patch test reactions to potassium dichromate (Cr), nickel sulfate (Ni), methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI), or p-phenylenediamine. Moreover, a control (pet.) patch and an irritant (SLS) patch were applied. After 3 days, the stratum corneum from tested sites was collected, and NMF levels and corneocyte morphology, expressed as the amount of circular nanosize objects, quantified according to the Dermal Texture Index (DTI), were determined.
Among allergens, only MCI/MI reduced NMF levels significantly, as did SLS. Furthermore, only MCI/MI caused remarkable changes at the microscopic level; the corneocytes were hexagonal-shaped with pronounced cell borders and a smoother surface. The DTI was increased after SLS exposure but not after allergen exposure.
MCI/MI significantly decreased NMF levels, similarly to SLS. The altered corneocyte morphology suggests that skin barrier damage plays a role in the pathogenesis of MCI/MI contact allergy. DTI seems to differentiate reactions to SLS from those to the allergens tested, as SLS was the only agent that caused a DTI increase.”
© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd