Dermis

The papillary layer is the thin outermost dermal layer, consisting of loosely interwoven collagen and elastin fibers. 

This region has a rich supply of capillary networks called the subpapillary plexus. Nutrients diffuse through these capillaries into the cells of the stratum basale, the deepest layer of the epidermis and help the keratinocytes to grow and develop.

In addition, this region is enriched with the lymphatic system, nerve fibers, and phagocytes.

Dermal papillae also have free nerve endings and touch receptors called Meissner's corpuscles.

The surface area of this layer is increased by the nipple-shaped structures called dermal papillae that project into the overlying epidermis, interdigitating with rete pegs.

In contrast to the thin skin, which has few and smaller papillae, the thick skin of the palm and sole has closely placed and much larger papillae resulting in prominent ridges and grooves organized in curved parallel lines.