Abstract
Skin serves as a protective barrier against invasion by pathogens and harmful antigenic particles. Filaggrin is a key structural protein that facilitates terminal differentiation of the keratinocytes and formation of the skin barrier. Since the establishment of a sequencing method for the entire filaggrin gene (FLG) in 2006, approximately 40 loss-of-function FLG mutations have been identified in patients with ichthyosis vulgaris and/or atopic dermatitis (AD). Notably, there is a clear difference in filaggrin genetics between the European and Asian races. Overall, approximately 25–50% of AD patients have been found to harbor filaggrin mutations as a predisposing factor. In addition, filaggrin mutations are significantly associated with asthma. The restoration of skin barrier function seems a feasible and promising strategy for prophylactic treatment of AD patients with FLG mutations. This article reviews the discovery of filaggrin mutations; their association with AD, asthma and other atopic diseases; and FLG-related potential treatment strategies.
Financial & competing interests disclosure
This work was supported in part by Grants-in-Aid from the Ministry of Education, Science, Sports, and Culture of Japan to M Akiyama (Kiban B 20390304) and by a grant from Ministry of Health, Labour and Welfare of Japan (Health and Labour Sciences Research Grants; Research on intractable diseases) to H Shimizu. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.