M2-like, dermal macrophages are maintained via IL-4/CCL24–mediated cooperative interaction with eosinophils in cutaneous leishmaniasis
Sang Hun Lee, Mariana M. Chaves, Olena Kamenyeva, Pedro Henrique Gazzinelli-Guimarães, Byunghyun Kang, Gabriela Pessenda, Katiuska Passelli, Fabienne Tacchini‐Cottier, Juraj Kabát, Elizabeth A. Jacobsen, Thomas B. Nutman, David L. Sacks
Abstract
infected dermis is not clear. Here, we show that, in infected mice lacking IL-4/13 from eosinophils, dermal TRMs shifted to a proinflammatory state, their numbers declined, and disease was attenuated. Intravital microscopy revealed a rapid infiltration of eosinophils followed by their tight interaction with dermal TRMs. IL-4-stimulated dermal TRMs, in concert with IL-10, produced a large amount of CCL24, which functioned to amplify eosinophil influx and their interaction with dermal TRMs. An intraperitoneal helminth infection model also demonstrated a requirement for eosinophil-derived IL-4 to maintain tissue macrophages through a CCL24-mediated amplification loop. CCL24 secretion was confined to resident macrophages in other tissues, implicating eosinophil-TRM cooperative interactions in diverse inflammatory settings.