Dermal Papilla

The dermal papilla is formed by condensation of dermal fibroblasts lying under the forming epidermal placode. Reciprocal signaling between the mesenchymal condensations and the placode leads to formation of mesenchyme-derived dermal papilla inside the epithelial envelope. The dermal papilla functions as a signaling center during initial hair morphogenesis in the embryo, as well as during the adult hair cycle. The dermal papilla transmits signals to the surrounding epithelium, maintaining its proliferation and differentiation into the various cell types of the growing hair shaft.