Humoral immune response to Klebsiella capsular polysaccharides in HLA-B27-positive patients with acute anterior uveitis and ankylosing spondylitis

Klebsiella is suggested to trigger ankylosing spondylitis (AS) and acute an terior uveitis (AAU) in HLA-B27-positive individuals. Previous investigatio ns showed an increased antibody response to the Klebsiella capsular types K 76, K36, and K50 in sera from HLA-B27-positive AS patients. In the present study the prevalence and titers of antibodies against Klebsiella capsular a ntigens were measured by means of an ELISA in 32 sera from HLA-B7-positive AAU patients either with (n= 10) or without AS (n=22) and compared with ser a from HLA-B27-negative AS-patients (n = 13). Sera from either HLA-B27-posi tive (rr = 45) or negative (ir = 40) healthy individuals served as control. Sera from HLA-B27-positive AAU with or without AS showed significantly hig her antibody prevalence and IgG-titers against capsular antigens of the Kle bsiella serotypes K26, K36, and K50 when compared with sera from HLA-B27-ne gative AS patients or with healthy controls. These results might be taken t o indicate the predominance of these serotypes in the HLA-B27-associated AS and AAU.