Saccharomyces boulardii prevents oral polio virus vaccine induced IgA nephropathy in mice

EVALUATION OF THE EFFECT OF THE PROBIOTIC SACCHAROMYCES BOULARDII ON THE DEVELOPMENT OF EXPERIMENTAL IgA NEPHROPATHY IN MICEIntroduction: IgA nephropathy (IgAN) is associated with a primary defect in mucosal IgA response leading to increased antigenic stimuli reaching to bone marrow. It has a temporal relation to mucosal infections. Enteric flora plays an important role on development and function of both mucosal and systemic immünity. Probiotics regulate specific and innate immünity by maintaining microbial balance in the gut. Saccharomyces boulardii (S.boulardii) increases intestinal secretory IgA (sIgA) production, protects the host from enteric infections and also prevents atopic and immünoinflammatory diseases like inflammatory bowel diseases. We evaluated the effect of S.boulardii on experimental IgAN, induced by oral poliovirus vaccine (OPV) in the mice.Methods: Four groups of male BALB/c mice, each including eight animals, were formed. The mice in Group 1 were immünized enterally by OPV through direct injection to stomach of 0.2 mL solution including 107/mL for each of the three strains at the onset, 2nd and 4th weeks. Those on Group 2 were also given S.boulardii, added to the drinking water at a dose of 3x108 CFU/mL throughout the study, in addition to OPV immünization. The mice in Group 3 were given only S.boulardii, while those in Group 4 received no treatment. At 6th week, after urine and serum samples were obtained for urinalysis and creatinine measurements, all the animals were sacrificed to get their kidneys for histopathological evaluation.Results: Urinalysis and serum creatinine levels were normal in all groups. While the mice in Group 1 had mild to moderate mesangial cell proliferation and matrix widening, there was no remarkable histological changes in the other groups including the mice given OPV + S.boulardii. Tubular atrophy, interstitial inflammation and fibrosis were not present in any of the groups. Immunofluorescence microscopy revealed universal deposition of IgA in OPV group, while there was no IgA deposition in the other groups apart from minimal deposition in one or two mice. Three of the mice in Group 1 also had C3 deposition which was totally absent in other groups. Electron microscopy revealed mesangial proliferation along with matrix expansion, focal basement membrane thickening and electron-dense deposits in the mesangial area in only OPV group and the other groups were normal.Conclusion: Enteral S.boulardii administration prevented experimental IgAN development by OPV in mice.Key words: IgA nephropathy, probiotics, Saccharomyces boulardii, oral poliovirus vaccine.