IL17A and myeloid sarcoma: Clinical observations have shown that Secukinumab, an IL-17A inhibitor, can alleviate symptoms in patients with comorbid AS and MS, suggesting that Th17-mediated inflammation may play a crucial role in the pathogenesis of both diseases.[23] Moreover, increasing evidence has shown that the microbiome has a crucial role in determining the development of acquired immune responses and thereby might predispose to immune-mediated inflammatory diseases, including AS and MS.