655 Origin and functions of the corneocyte lipid envelope

The -hydroxyceramide (-OH-Cer)-enriched, corneocyte lipid envelope (CLE) lies external to the cornified envelope (CE), but neither its functions nor origin are known. To address its functions, we assessed biopsies from recessive congenital ichthyosis (ARCI) patients and animals with compromised -OH-Cer generation. While both CLEs and CEs were attenuated, topical acylCer applications to ichthyin-deficient canines and transgenic rescue of fatp4 knockout mice restored both CLEs and CEs. The CLE also is required for lamellar membrane formation, because secreted lamellar body (LB)-derived lipids fail to transform into lamellar membranes in Alox12B-/-, despite unimpaired acylglucosylCer production/secretion.

Source: Journal of Investigative Dermatology - April 19, 2018 Category: Dermatology Authors: D. Crumrine, D. Khnykin, P. Krieg, M. Man, A. Celli, T. Mauro, G. Menon, E. Mauldin, J. Miner, A. Brash, E. Sprecher, F. Radner, K. Choate, D.R. Roop, Y. Uchida, R. Gruber, M. Schmuth, P. Elias Tags: Epidermal Structure and Barrier Function Source Type: research