The Effect of HAF on CD44v3, pro-HB-EGF, and HB-EGF in Mouse Skin; CD44 and erbB1 Association In Vitro and In Vivo; CD44, HA, and erbB1 Levels in Young and Elderly Skin

<div><p>(A) HAFi induces expression of CD44v3, pro-HB-EGF, and active HB-EGF in mouse skin. Western blot analysis on the protein extracts of vehicle- or HAFi-treated SKH1 hairless mice for CD44v3 (∼200 kDa [a]), active HB-EGF (∼15 kDa [b]), pro-HB-EGF (∼25 kDa [c]), and loading control α-tubulin (50 kDa [d]).</p> <p>(B) CD44 associates with erbB1 in keratinocytes in vitro and in vivo. Western blot analysis of anti-CD44 antibody immunoprecipitates of protein extracts of cultured keratinocytes (a) or epidermis of DBA/1 mouse skin immunoblotted with anti-erbB1. Mock, isotype-matched rat IgG; beads, protein A+G agarose beads treated with anti-CD44 antibody.</p> <p>(C) CD44, HA and erbB1 levels are diminished in atrophic human skin. CD44 (a), HA (b), and erbB1 (c) expression in forearm skin biopsy specimens of young adults (control) and elderly patients with skin atrophy. The results are presented as the mean CD44, HA, or erbB1 concentration ± SEM of three subjects per group. *<i>p</i> < 0.05 versus young controls (Student's t-test).</p>