9.4:
Papillary 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.
9.4:
Papillary Dermis
Dermis
The dermis might be considered the "core" of the integumentary system, as distinct from the epidermis and hypodermis. It contains blood and lymph vessels, nerves, and other structures, such as hair follicles and sweat glands. The dermis is made of two layers of connective tissue that comprise an interconnected mesh of elastin and collagenous fibers, produced by fibroblasts.
Papillary Layer
The papillary layer is made of loose, areolar connective tissue, which means the collagen and elastin fibers of this layer form a loose mesh. This superficial layer of the dermis projects into the stratum basale of the epidermis to form finger-like dermal papillae. Within the papillary layer are fibroblasts, a small number of fat cells (adipocytes), and an abundance of small blood vessels. In addition, the papillary layer contains phagocytes, defensive cells that help fight bacteria or other infections that have breached the skin. This layer also contains lymphatic capillaries, nerve fibers, and touch receptors called the Meissner corpuscles.
This text is adapted from Openstax, Anatomy and Physiology 2e, Section 5.1: Layers of the Skin