ABSTRACT
The insidious onset and slow progression of Ankylosing spondylitis (AS), combined with the difficulty in making an early definitive diagnosis and assessing disease activity, make the scientific investigation of this disease a difficult problem. Some of the first experimental evidence for the possible involvement of a microbiological component in the pathogenesis of AS was obtained by R. W Ebringer et al. The insidious onset and slow progression of AS, combined with the difficulty in making an early definitive diagnosis and assessing disease activity, make the scientific investigation of this disease a difficult problem. The initial reports of Ebringer et al. dealing with cross-reactivity between certain strains of enteric bacteria and human lymphocyte antigen (HLA) B27-positive lymphocytes prompted many groups to initiate various immunochemical studies on the possible role of bacteria in the pathogenesis of AS. The discovery of the AS-HLA-B27 association in 1973 highlighted the possible role HLA antigens may have in disease susceptibility.
