Impact of Substrate Stiffness on Dermal Papilla Aggregates in Microgels

The document from 2018 presents a study that explored how the stiffness of poly(ethylene glycol) diacrylate (PEGDA) hydrogel substrates affects dermal papilla (DP) cell aggregates, which are important for hair follicle formation and growth. The study found that DP cell viability was not significantly affected by the stiffness of the hydrogels. However, cell attachment and spreading were reduced on softer hydrogels, and gene and protein expression analyses indicated that softer substrates (5% PEGDA) led to higher expression of key inductivity markers (Axin2, BMP4, and Noggin) associated with hair follicle regeneration. These results suggest that softer hydrogel substrates may be more suitable for supporting DP cell functions relevant to hair growth. The study included n=3 for rheological and gene expression analysis and n=12 for cell viability assessment, with statistical significance determined by ANOVA tests.