The
bacterial extract, Uro-Vaxom, which consists of immunostimulating components derived from 18 Escherichia coli strains, was used for the prophylaxis of recurrent
cystitis. To evaluate the anti-inflammatory effect of E. coli extract, we measured the
cytokine levels of bladder tissue after
oral administration and analyzed bladder
inflammation by histopathologic examination in a model of
lipopolysaccharide (LPS)-induced
cystitis in mice. After oral administering the E. coli extract for 10 days, the
cytokine [
interleukin-6 (IL-6),
IL-10,
monocyte chemoattractant protein-1,
interferon-gamma (IFN-gamma),
tumor necrosis factor-alpha, IL-12p70] levels present in the bladder of female Balb/C mice were determined using a cytometric bead array. The bladder macrophage inflammatory protein-2 level was also measured using a sandwich
enzyme immunoassay. After immunization with the E. coli extract, E. coli LPS was instilled into the bladders intravesically. Twenty-four hours later, the mice were sacrificed and the level of bladder
inflammation was quantified using the bladder inflammatory index (BII). Significant changes in the bladder
IL-6 and IFN-gamma levels were observed after the E. coli extract treatment. Secretions of the other
cytokines were not stimulated by the E. coli extract. The bladder instilled with LPS had high
inflammation scores for
edema, leukocyte infiltration, and
hemorrhage in the saline treated control mice. In contrast, the E. coli extract treated mice exhibited mild
inflammation of their bladders with a significant reduction in the BII scores compared with the controls. These findings might explain the anti-inflammatory effect of the E. coli extract demonstrated in clinical studies.