A possible role of Eubacterium and Peptostreptococcus species in the aetiology of Crohn's disease

Abstract

The faecal flora of patients with Crohn's disease has been found to contain higher numbers of anaerobic gram-negative rods and gram-positive coccoid rods than the flora of healthy subjects. In a considerable percentage of sera from patients with Crohn's disease, agglutinating antibodies were found against four strains of the coccoid rods, in contrast to sera from patients with ulcerative colitis, other diseases and healthy subjects. In the present study, coccoid strains C₁₈, Me₄₆ and Me₄₇ were found to activate complement by the alternative pathway. IgG antibodies to strains Me₄₄, C₁₈ and Me₄₇ had opsonic properties but those to strain Me₄₆ failed to induce phagocytosis. The data suggest an inadequate immune defence against strain Me₄₆ in patients with Crohn's disease. The possible role of strain Me₄₆ in the pathogenesis of Crohn's disease is discussed.