IL17A and inflammatory bowel disease: The main immune response pathways include inflammatory bowel disease (IBD), leukocyte transendothelial migration, complement and coagulation cascades, the Fc epsilon Ri signalling pathway, the chemokine signalling pathway, the toll-like receptor signalling pathway, the B cell receptor signalling pathway, systemic lupus erythematosus, platelet activation, and the IL-17 signalling pathway.