The epidermis consists of multiple layers and cells. From deep to superficial the layers include: stratum basale, spinosum, granulosum, lucid, and corneum. Keratinocytes synthesize the protein keratin. Stem cells differentiate into keratinocytes. Melanocytes synthesize the pigmented protein melanin. Tactile/Merkel cells are associated with a dermal nerve fiber, together called a tactile disc and function in reception for touch. Dendritic/Langerhans cells function in immune response.