The healing power of painful memories

Our body’s epithelia are barriers that interface with the terrestrial environment and routinely experience inflammation. Although a vast majority of these inflammatory reactions resolve, they imprint the tissue with a memory. Cells of the immune system are traditionally thought to be the bearers of this memory, allowing them to react faster to subsequent inflammatory pressures (1, 2). Yet, barrier tissues are composites of epithelial, mesenchymal, nervous, vascular, and immunological networks working in unison to sustain optimal function in health and disease. The question of whether tissue-resident cells, distinct from the immune system, are entrained in response to a perturbation remains to be addressed.