Isolation and Flow Cytometry Analysis of Macrophages from the Dermis.

The dermis contains a dense network of tissue macrophages, which contribute to tissue homeostasis, inflammation, and pathogen clearance. Dermal macrophages are partly replenished by circulating monocytes, which fuel the resident population, especially in case of tissue damage or inflammation. The complexity of the tissue, containing blood and lymphoid vessels, hair bulbs, sebaceous glands, and peripheral nerves, allows for the development of distinct macrophages populations. In steady state, discrete subtypes can be distinguished due to their surface marker expression and localization within the dermis. In this chapter, we describe how to extract dermal macrophages from the skin and highlight different gating strategies to identify monocyte and macrophage populations.