Differential patterns of filaggrin expression in lamellar ichthyosis

Lamellar ichthyosis (LI) is a rare genetic and congenital disturbance of ke ratinization that is phenotypically and genotypically heterogeneous. Filagg rin is one of the major components of the stratum corneum situated in the p rotein matrix and the cornified envelope, In view of the heterogeneity of L f, this study aimed at exploring filaggrin expression in the skin of patien ts suffering from the disease, Epidermal filaggrin expression was determine d using immunohistochemical techniques and Western blot in 12 patients with LI and the findings were compared with those observed in four normal contr ols and eight patients with ichthyosis vulgaris, With Western blot, six dif ferent patterns of filaggrin expression were detected. The patients with si milar clinical manifestations showed a similar pattern, as did members of t he same family. Overall, higher filaggrin expression in scales correlated w ith a better prognosis. In patients receiving retinoids no variations in fi laggrin expression during treatment were detected. Our results suggest that LI is heterogeneous as regards filaggrin expression, Filaggrin could there fore be used as a prognostic marker as well as being a marker of the basic defect involved in LI.