IL-17 functions in host defense against extracellular bacterial and fungal infections and contributes to the pathogenesis of various autoimmune inflammatory diseases. CD4+ Th17 cells are a major source of IL-17 in vivo and play a central role in the pathogenesis of autoimmune diseases. Since the discovery of Th17 cells in 2005, there has been rapid progress in our understanding of the roles of IL-17-producing T cells in innate immunity to infection, the plasticity of Th17 cells, and genetic diseases associated with Th17 defects. The IL-17 pathway has been shown to be an attractive therapeutic target in many autoimmune and inflammatory disorders.

Most Th17 cells were found to reside in the barrier tissues, including respiratory and intestinal tracts as well as skin. Myelin-specific Th17 cells can also penetrate the blood–brain barrier (BBB) under inflammatory conditions and cause multiple sclerosis (MS). Cytokines produced by these Th17 and non-Th17 cells including γδ-T cells and innate lymphoid cells play critical roles in regulating tissue homeostasis and inflammation.

We invite scientists to contribute original research and review articles that will help the field to understand the role of IL-17-producing cells in diseases. We encourage submission of manuscripts on studies using animal models as well as disease progression in patients who suffer inflammatory conditions in barrier tissues including cancers.

Potential topics include but are not limited to the following:

• Identification and regulation of specific cell types of IL-17 producing cells in various types of barrier tissues as well as IL-17-producing cells penetrate barriers
• Antigen specificity of Th17 cells in barrier tissues
• Mechanisms by which IL-17-producing cells penetrate barriers
• Aberrant expression of IL-17 and IL-17 signatures in animal models and clinical specimens as well as rapid and accurate diagnostics to swiftly determine appropriate treatments for infection and inflammation
• Cross talk between IL-17 signaling and other pathways in disease pathogenesis and progression
• Genetic variations in the IL-17 pathway and susceptibility to diseases
• T cell plasticity, preferentially Th17 cell, in autoimmune disease including MS and in tumor development and cancer immunotherapy