Supplementary Figure 1: Reduced-serum methods for contact-based co-culture of human dermal fibroblasts and epidermal keratinocytes

Suppl Figure 1. Morphology and proliferation of HDFa and HaCaT, mono-culture and co-culture, under different media conditions. (A) HDFa growing in Fibroblast Growth Medium (FGM; containing 2% FBS and growth factors) with characteristic spindle-shaped morphology and HaCaT (immortalized) growing in Keratinocyte Growth Medium (KGM; serum-free containing growth factors) with typical mosaic, cobblestone morphology. (B) Co-seeding of HDFa and HaCaT (in a 1:1 ratio) in MEM alone (with no growth supplements or FBS; a-d) and MEM with added 10% FBS (no growth supplements) (e-h). In the absence of serum and growth supplements (a-d), HDFa show poor proliferation, and HaCaT fail to attach and proliferate. In the presence of 10% FBS (no growth supplements, e-h), HDFa and HaCaT shows minimal proliferation, but HDFa do not form typical sheaths around HaCaT colonies (Day 3 onwards). Scale bars = 150 µm.