HOST-MICROFLORA INTERACTION IN SYSTEMIC LUPUS-ERYTHEMATOSUS (SLE) - CIRCULATING ANTIBODIES TO THE INDIGENOUS BACTERIA OF THE INTESTINAL-TRACT

Experimental data suggest a role for the microflora in the disease exp ression of systemic lupus erythematosus (SLE). In active SLE anti-ds-D NA antibodies are supposed to be pathogenic by forming immune complexe s with DNA. Bacteria might induce the production of anti-ds-DNA antibo dies. To explore the relation between the host and his microflora in S LE in comparison with healthy controls we studied the prevalence of sy stemic antibodies to faecal bacteria that were discriminated by their morphology by indirect immunofluorescence. IgM titres against their ow n faecal microflora were found to be lower both in active and inactive SLE when compared to healthy individuals. IgG-dass antibacterial anti bodies were increased in inactive SLE but decreased in active SLE comp ared to inactive SLE and healthy controls, although plasma levels of t otal IgG were almost doubled in active SLE. The lower IgG antibacteria l antibody titres in active SLE might possibly result from sequestrati on of these IgG antibodies in immune complexes, indicating a possible role for antibacterial antibodies in exacerbations of SLE.