CRP and spondylitis: The following categorical clinical parameters were not associated with enrichment of CD27-CD38lowCD21low B-cells in patients with axSpA: being naïve for biological DMARDs, non-radiographic disease, sex, symptom duration ≥10 years, C-reactive protein (CRP) ≥5 mg/L and high disease activity defined by the Ankylosing Spondylitis Disease Activity Score (ASDAS) ≥2.1 (Figure 4A).