Neutrophil functions, spondylarthropathies and HLA-B27: a study of 43 patients.

OBJECTIVES: Several hypotheses have been proposed regarding the role of HLA-B27 antigen in the pathogenesis of the spondylarthropathies. METHODS: We studied some neutrophil functions in vivo in patients affected by ankylosing spondylitis or by reactive arthritis, with or without HLA-B27, and in healthy control subjects. In vivo neutrophil migration was investigated by Senn's skin window technique. An adhesion assay was also conducted and superoxide production was measured in circulating and migrating neutrophils after different stimuli. RESULTS: Neutrophil migration in vivo was higher in the HLA-B27 positive patients than in the controls, while no difference was found between the HLA-B27 negative patients and controls. Our data showed an increased response to formyl-methionyl-leucyl-phenylalanine by circulating neutrophils in the patients with ankylosing spondylitis, both HLA-B27 positive and negative, in comparison with all the other subjects. CONCLUSIONS: Our results revive the question of the role of HLA-B27 in the regulation of neutrophil migration; the reported in vivo priming of circulating neutrophils seems to be related to ankylosing spondylitis rather than to HLA-B27.