Abstract
Background: To determine whether optimal use of serial measurements of serum levels of soluble cell adhesion molecules (CAM) can improve monitoring of disease activity in SLE. Methods: Serum levels of soluble CAM and conventional SLE biomarkers were measured in serial samples (n = 80) from 21 SLE patients during and after flare and correlated in longitudinal analysis with disease activity determined by ECLAM score. Blood samples from a second cohort of 34 SLE patients were subject to flow cytometry to correlate serum biomarkers with B cell subsets. Results: By adjusting for the baseline level (at the first visit), delta soluble vascular cell adhesion molecule-1 (sVCAM-1) showed stronger correlation with changes in ECLAM score and improved sensitivity and specificity for identifying SLE responders versus non-responders compared to conventional SLE biomarkers including anti-dsDNA antibody titre and complement C3. Multiple regression analysis identified delta sVCAM-1 as the best marker of SLE clinical response. sVCAM-1 levels were significantly correlated with CD95+CD27+ activated memory B cells, CD95+ plasmablasts and circulating plasma cell numbers in SLE patients. Conclusion: Subtracting a baseline level of sVCAM-1 for each individual substantially improved its utility as a biomarker. Delta sVCAM-1 was superior to conventional SLE biomarkers for monitoring changes in disease activity. This suggests that serial monitoring of serum sVCAM-1 trends should be considered in SLE patients to document responses to treatment. We hypothesise that the correlation between activated B cell subsets and circulating plasma cell numbers with soluble VCAM-1 serum levels in SLE may relate to the important role of VCAM-1 in B lymphocyte survival and maturation in bone marrow and secondary lymphoid tissues.
Original language | English |
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Article number | 5 |
Journal | Arthritis Research and Therapy |
Volume | 18 |
Issue number | 1 |
DOIs | |
Publication status | Published - 8 Jan 2016 |
Keywords
- Anti-double-stranded DNA antibodies
- Biomarker
- CD95
- Complement C3
- Memory B cells
- Plasma cells
- Plasmablasts
- Soluble cell adhesion molecules
- Systemic lupus erythematosus
- Vascular cell adhesion molecule-1