Production of anti-Candidaantibodies in mice with gut colonization ofCandida albicans

[摘要] BACKGROUND: Production of antibodies that are specific for allergens is an important pathological process in inflammatory allergic diseases. These contain the antibodies against antigens ofCandida albicans, one of the normal microbial flora in an intestinal tract. We studied the effects of the prednisolone administration on the production of anti-Candidaantibodies in the gastrointestinallyC. albicans-colonized mice.Methods and Materials: BALB/c mice, treated with antibacterial antibiotics to decontaminate indigenous intestinal bacterial flora, were inoculated intragastrically withC. albicans. The mice, in whichC. albicansgrows intestinally, were administered prednisolone to induce temporary immunosuppression. TheCandidagrowth in their intestinal tract and their antibody response toCandidawere examined.Results: Antibiotic treatment allowed establishment ofC. albicansgastrointestinal colonization, but did not cause subsequent systemic dissemination ofC. albicansin all the animals. When these animals received an additional treatment with prednisolone, they showed a significantly higher population ofC. albicansin their feces than those of animals treated with antibiotics alone, and the organisms were recovered even from their kidney. This systemic dissemination byC. albicansappeared to be temporal, because all the mice survived without any symptoms for more than 2 months. Examination of the serum titers of total immunoglobulin (Ig)E antibodies and specific IgE and IgG antibodies againstCandidaantigens demonstrated that titers of total IgE increased, partially by day 14 and clearly at day 27, in prednisolone-treatedCandida-colonized mice. Without prednisolone treatment, an increment of the serum titer was scarcely observed. By day 27, corresponding to the increase of total IgE, the anti-CandidaIgE and IgG titer increased in mice of the prednisolone-treated group.Conclusion: Administration of prednisolone toCandida-colonized mice can induce production of the IgG, IgE antibodies againstCandidaantigens, perhaps through temporal systemic dissemination ofCandidafrom the intestinal tract.

[学科分类] 生理学与病理学