3D visualization of epidermal Langerhans cells.

Langerhans cells (LCs) are intraepidermal dendritic cells that extend their dendrites between keratinocytes to form a dense network that covers the entire body. The mammalian epidermis has two diffusion barriers, the stratum corneum and tight junctions (TJs). In their resting state, LCs sit underneath these two barriers. Once activated, LCs elongate their dendrites to dock with, or penetrate through, TJs, which allows them to survey the environment between the two barriers. Here, we describe a method to visualize this dynamic interaction of TJs and LCs in 3D by using mouse ear epidermal sheets.