Topic Overview:

Within the last decade, understanding of autoimmune inflammatory diseases has been revolutionized by the discovery of a new CD4+  helper T cell subset: Th17 cells. Named for their production of IL-17, a pro-inflammatory cytokine with effects on multiple tissue targets, Th17 cells and pathways associated with them are now implicated in the pathogenesis of psoriasis, inflammatory bowel disease, rheumatoid arthritis, spondyloarthropathies, multiple sclerosis, uveitis, and certain forms of severe asthma. It is now clear that IL-17, while important, is only one part of the arsenal available to Th17 cells, and they also express numerous other factors including GM CSF (granulocyte-macrophage colony-stimulating factor) and IL-22 to promote inflammation.

McGeachy aims to understand the mechanisms behind inflammatory autoimmune diseases and investigates activation and regulation of Th17 cells and how these impact disease pathogenesis in various tissues. McGeachy has a particular focus on the functions of the cytokine IL-23 in promoting Th17-mediated inflammation. IL-23 has been found to be critical in driving the differentiation of activated Th17 cells towards inflammatory effector cells that migrate into target tisuues to initiate disease.