Uncontrolled production or function of TNF has been linked to the development of chronic inflammatory diseases (Alexopoulou et al., 1997; Lee et al., 2013) such as rheumatoid arthritis (RA), inflammatory bowel disease (IBD), psoriasis, psoriatic arthritis (PsA), ankylosing spondylitis and specific types of juvenile idiopathic arthritis (JIA) as was recently reviewed (Kalliolias and Ivashkiv, 2016). Here, TNF is linked to ankylosing spondylitis.