The majority of current in vitro skin models lack an inflammatory system, vasculature, and other characteristics of native skin, making them less relevant for the study of biological or pathological processes related to the human skin. To fill this gap, we developed a skin model containing immune and endothelial cells. Skin biopsies were enzymatically treated to isolate epidermal and dermal cells. Following isolation, the epidermal fraction contained keratinocytes, melanocytes, lymphocytes T and Langerhans cells while the dermal fraction contained fibroblasts, endothelial cells and immune cells (macrophages, lymphocytes, dendritic cells). Fibroblasts were first cultured for 3 weeks with ascorbic acid to stimulate the production of an extracellular matrix surrounding cells. The dermal fraction, that contained immune cells of autologous origin to avoid activation of the immune system, was then seed onto one sheet while the epidermal fraction was seeded on another sheet. These two sheets were then superimposed and raised at the air-liquid interface to stimulate epidermis differentiation. After 2 weeks, a 3D skin model containing immune cells isolated from the same donor was obtained. Histological studies revealed a stratified epidermis found on top of a dermis composed of matrix and cells. Immunofluorescence staining showed viable autologous myeloid cells, mast cells and T lymphocytes as well as an autologous capillary network (CD31+)) in the dermis. The creation of this first 3D model containing autologous immune cells paves the way to increase knowledge into skin homeostasis as well as in diseases.

A NEW 3D SKIN MODEL CONTAINING AUTOLOGOUS IMMUNE CELLS RECONSTRUCTED BY TISSUE ENGINEERING