Patients with SLE, myasthenia gravis, Sjogren’s syndrome, and rheumatoid arthritis have increased numbers of TFH cells20–31, and altered TFR to TFH cell ratios have been observed in mouse models of arthritis and patients with ankylosing spondylitis, Sjogren’s syndrome, myasthenia gravis, and multiple sclerosis32–36. Here, TFRC is linked to ankylosing spondylitis.