IL-17 receptor and IL-22 receptor signaling in Citrrobacter rodentium infection

Th17 cells producing cytokines, IL-17A and IL-22 are important key player in host defense. We have reported that intestinal epithelial expression of IL-17 receptors in gut epithelial cells control the development of microbiota. To study the roles of these receptors in response to an attaching and effacing pathogen we challenged Citobacter rodenium (C. rodentium) to intestinal epithelial specific IL-17RA or IL-22RA1 KO mice. Conditional deletion of Il17ra or Il22ra1 resulted in increased bacterial growth in the colon as well as enhanced dissemination to the spleen. It suggested both cytokine receptors are required for control of this infection. In addition this was supported by unbiased RNAseq analysis of the colonic epithelium that showed diminished expression of Pigr, Duox2 and Duoxa2 in the absence of IL-17RA signaling and reduced Bcl3 expression in the absence of IL-22ra1 expression. To elucidate whether production from epithelial cells effect bacteria killing we cultured crypt and stimulated IL-17A. It resulted in increasing Pigr, Duoxa2 and Duox2 were associated with increasing bacteria killing. Pigr binds dimeric IgA and translocation into lumen from lamina propria, while Duox2 and Duoxa2 make complex and produce hydrogen peroxide into lumen from apical epithelial cell membrane. These result suggested mucosal immunity to C. rodentium requires both IL-17RA and IL-22ra1 signaling and that IL-17RA regulates transcytosis of C. rodentium specific IgA as well as luminal hydrogen peroxide concentrations to control bacterial growth. In contrast, Il-22Ra1 regulates epithelial Bcl3 expression, which restrains TNFα and NF-κB signaling in the colonic epithelium.

Disco-computed tomography in extraforaminal and foraminal lumbar disc herniation: influence on surgical approaches

Between January 1990 and February 1992, a total of 301 patients underwent discectomy for lumbar disc herniation; 29 had an extreme lateral herniation, i.e., foraminal or extraforaminal. The intervertebral foramen is a three-dimensional area demarcated primarily by the pedicles; we call it the lateral interpedicular compartment. The extraforaminal zone is the space outside the lateral border of the pedicles. All patients were evaluated by computed tomography (CT), water soluble myelography, postmyelographic CT scanning, or magnetic resonance imaging. Fifteen patients consecutively underwent disco-enhanced CT to adjust a correct diagnosis and to distinguish extraforaminal from foraminal herniation. In 10 cases of extraforaminal herniation, a selective radicular decompression with good-to-excellent clinical results was achieved by an extra-axial lateral decompression of the interpedicular compartment, with preservation of the facet joint. The operative target was the lateral aspect of the pars interarticularis and not the intertransverse space, as previously described. In two cases of both foraminal and extraforaminal herniation, the same technique was used. Fourteen patients with foraminal disc herniation and three patients with both foraminal and extraforaminal herniation underwent a standard intervertebral foraminotomy. An accurate preoperative diagnosis established by disco-CT is crucial in order to select the most suitable surgical approach.