IL17A and Langerhans cell histiocytosis: By binding to CCL20, CCR6 recruits IL-17-secreting inflammatory cells into the inflammatory environment.30 IL-17 is secreted by a highly heterogeneous cell population, which can be classified into Th17, Th22, and T117 subpopulations and unclassified or intermediate populations.31–33 Th17 has been reported as a potential therapeutic factor in LCH-related bone destruction.