gms | German Medical Science

Background: Seronegative spondylarthritides (SPA) may significantly affect sacroilical, intervertebral, and peripheral joints. Articular inflammation is typically accompagnied by increased neovascularization. In recent years, the Endothelial Progenitor Cells system has been show to critically perpetuate vascular repair under pathological circumstances. Aim of the study was to evaluate circulating EPCs in SPA with special attention on parameters of disease activity and disease-associated joint damage.

Methods: Fifty SPA patients were recruited from the Clinic of Nephrology and Rheumatology of the University Hospital Göttigen. Disease activity and functional impairment were quantified by using standardized parameters (BASDAI, CRP, FFD - Finger Floor Distance, Ott´ sign). Circulating EPCs were enumerated by FACS analysis and EPC regenerative activity was analyzed by using a Colony Forming Unit assay. Serum levels of vasomodulatory mediators were quantified by ELISA.

Results: EPC colony numbers were lower in SPA as compared to healthy controls and females displayed higher colony numbers than males. In addition, fewer colony numbers were observed in smokers, in patients with a BASDAI of below 4 and in those with hypertension. Circulating CD133+/KDR+ cells did not differ between the respective groups. Follow-up analysis, performed after a mean period of 33 months did not show any differences in gender, colony formation, CD133+/KDR+ cells, or serum levels of vasomodulatory mediators if related to the categories BASDAI, Ott ´sign, or FFD.

Conclusion: EPC colony formation is significantly affected in SPA with particularly low levels in males. However, EPC-related parameters of vascular regeneration do not allow to predict outcomes of disease activity-related or functional parameters.