Efficient keratinocyte differentiation strictly depends on JNK-induced soluble factors in fibroblasts - Schumacher, Marion; Schuster, Christian; Baars, Sebastian; Szabowski, Sibylle; Leowardi-Bauer, Christine; Schorpp-Kistner, Marina; Heß, Jochen; Angel, Peter; Hartenstein, Bettina (The journal of investigative dermatology, 2014)