Interleukin-25 Mediated Induction of Angiogenin-4 Is Interleukin-13 Dependent

<div><p>The intestinal surface is directly exposed to both commensal microorganisms as well as pathogens with a single layer of epithelium separating luminal microorganisms from internal tissues. Antimicrobial peptides play a crucial role in allowing epithelial cells to contain in the lumen beneficial and pathogenic microorganisms. The commensal dependent, epithelial produced, Th2 cytokine IL-25 can induce IL-13 and potentially the antimicrobial peptide angiogenin-4. Here we show that IL-13 downstream of IL-25 is required to induce angiogenin-4. IL-25 mediated induction of angiogenin-4 is furthermore not dependent on IL-22 or IL-17.</p></div

Depletion of IL-13 abrogates rIL-25 induction of angiogenin-4.

<p>CBA/J mice were treated with 0.5 micrograms of recombinant IL-25 each day for a total 6 doses. Control mice received PBS. Recombinant IL-25 treated mice received 200μg anti-IL-13 antibody or isotype control on day 3 and on day 5. Angiogenin-4 relative expression was measured from cecal tissue, n = 5–8 (A). Histological scoring (1 to 5; low to high) for Angiogenin-4 in cecum from mice treated with PBS or rIL-25 with isotype control or rIL-25 with anti-IL-13 (B). Representative IHC staining for angiogenin-4 in samples of cecum tissue from PBS treated (C) or rIL-25 with isotype control (D) or rIL-25 with anti-IL-13 treated mice (E).</p

A Comprehensive Computational Investigation into the Conserved Virulent Proteins of Shigella species Unveils Potential Small-Interfering RNA Candidates as a New Therapeutic Strategy against Shigellosis

Shigella species account for the second-leading cause of deaths due to diarrheal diseases among children of less than 5 years of age. The emergence of multi-drug-resistant Shigella isolates and the lack of availability of Shigella vaccines have led to the pertinence in the efforts made for the development of new therapeutic strategies against shigellosis. Consequently, designing small-interfering RNA (siRNA) candidates against such infectious agents represents a novel approach to propose new therapeutic candidates to curb the rampant rise of anti-microbial resistance in such pathogens. In this study, we analyzed 264 conserved sequences from 15 different conserved virulence genes of Shigella sp., through extensive rational validation using a plethora of first-generation and second-generation computational algorithms for siRNA designing. Fifty-eight siRNA candidates were obtained by using the first-generation algorithms, out of which only 38 siRNA candidates complied with the second-generation rules of siRNA designing. Further computational validation showed that 16 siRNA candidates were found to have a substantial functional efficiency, out of which 11 siRNA candidates were found to be non-immunogenic. Finally, three siRNA candidates exhibited a sterically feasible three-dimensional structure as exhibited by parameters of nucleic acid geometry such as: the probability of wrong sugar puckers, bad backbone confirmations, bad bonds, and bad angles being within the accepted threshold for stable tertiary structure. Although the findings of our study require further wet-lab validation and optimization for therapeutic use in the treatment of shigellosis, the computationally validated siRNA candidates are expected to suppress the expression of the virulence genes, namely: IpgD (siRNA 9) and OspB (siRNA 15 and siRNA 17) and thus act as a prospective tool in the RNA interference (RNAi) pathway. However, the findings of our study require further wet-lab validation and optimization for regular therapeutic use for treatment of shigellosis

rIL-25 administration induces IL-13 expression.

<p>CBA/J mice were treated with 0.5 micrograms of recombinant IL-25 (closed square, n = 8) each day for a total of 5 doses and control mice received PBS (open circle, n = 7). IL-13 relative expression was measured from mouse cecal tissue and normalized with house keeping gene GAPDH and β actin.</p

rIL-25 administration induces angiogenin-4 expression.

<p>CBA/J mice were treated with 0.5 micrograms of recombinant IL-25 (triangle, n = 11) each day for a total of 10 doses over 10 days. Control mice received PBS (open circle, n = 11). Angiogenin-4 relative expression was measured from mouse cecal tissue and normalized with house keeping gene GAPDH and β actin (A). Histological scoring (1 to 5; low to high) for Angiogenin-4 in cecum from mice treated with PBS or rIL-25 (B). Representative IHC staining for angiogenin-4 in samples of cecum tissue from PBS treated (C) or rIL-25 treated mice (D).</p

rIL-13 administration induces angiogenin-4 expression.

<p>CBA/J mice were treated with 0.5 micrograms of recombinant IL-13 (triangle, n = 5) on each day for total 4 doses. Control mice received PBS (open circle, n = 5). Angiogenin-4 relative expression was measured from mouse cecal tissue and normalized with house keeping gene GAPDH and β actin (A). Histological scoring (1 to 5; low to high) for Angiogenin-4 in mouse cecum from PBS or rIL-13 treated mice (B). Representative IHC staining for angiogenin-4 in samples of cecum tissue from PBS treated (C) or rIL-13 treated mice (D).</p

rIL-25 administration increases angiogenin-4 expression in a dose dependent manner.

<p>CBA/J mice were treated with 0.5 micrograms of rIL-25 each day for a total 4 doses (triangle, n = 7) or 8 doses (inverse triangle, n = 5) and control mice received 4 or 8 doses of PBS (open circle, n = 7 for 4 doses and n = 5 for 8 doses). Angiogenin-4 relative expression was measured from mouse cecal tissue and normalized with house keeping gene GAPDH and β actin.</p

rIL-25 induced angiogenin-4 production is not significantly influenced by IL-17 or IL-22 blockade.

<p>CBA/J mice were treated with 0.5 micrograms of recombinant IL-25 each day for total 7 doses and control mice received PBS. rIL-25 treated mice received 200μg anti IL-17 antibody (inversed triangle) or 200μg anti IL-22 antibody (open square) or 200μg anti-IL-13 antibody (open circle), or isotype control on day 3, on day 5 and on day 7. Angiogenin-4 relative expression was measured from cecal tissue.</p

Risk Factors for Norovirus Infections and Their Association with Childhood Growth : Findings from a Multi-Country Birth Cohort Study

The prevalence of norovirus infections in different geographical locations and their attribution to childhood diarrhea is well established. However, there are no reports showing possible relationships of different norovirus genogroups with subsequent childhood malnutrition. In this study, we attempted to establish a potential association between asymptomatic norovirus infections with childhood growth faltering during. Non-diarrheal stools were collected from 1715 children enrolled in locations in a multi-county birth cohort study across eight different geographical locations and were assessed for norovirus genogroup I (GI) and norovirus genogroup II (GII). Asymptomatic norovirus GI infections were negatively associated with monthly length-for-age Z score/LAZ (β = -0.53, 95% CI: -0.73, -0.50) and weight-for-age Z score/WAZ (β = -0.39, 95% CI: -0.49, -0.28), respectively. The burden of asymptomatic norovirus GI infections was negatively associated with LAZ (β = -0.46, 95% CI: -0.67, -0.41) and WAZ (β = -0.66, 95% CI: -0.86, -0.53) at 2 years of age, whilst the burden of asymptomatic norovirus GII infections was negatively associated with WAZ (β = -0.27, 95% CI: -0.45, -0.25) at 2 years of age. Our findings warrant acceleration in attempts to develop vaccines against norovirus GI and norovirus GII, with the aim of minimizing the long-term sequelae on childhood growth.publishedVersionPeer reviewe

Role of Eosinophils and Tumor Necrosis Factor Alpha in Interleukin-25-Mediated Protection from Amebic Colitis

The parasite Entamoeba histolytica is a cause of diarrhea in infants in low-income countries. Previously, it was shown that tumor necrosis factor alpha (TNF-α) production was associated with increased risk of E. histolytica diarrhea in children. Interleukin-25 (IL-25) is a cytokine that is produced by intestinal epithelial cells that has a role in maintenance of gut barrier function and inhibition of TNF-α production. IL-25 expression was decreased in humans and in the mouse model of amebic colitis. Repletion of IL-25 blocked E. histolytica infection and barrier disruption in mice, increased gut eosinophils, and suppressed colonic TNF-α. Depletion of eosinophils with anti-Siglec-F antibody prevented IL-25-mediated protection. In contrast, depletion of TNF-α resulted in resistance to amebic infection. We concluded that IL-25 provides protection from amebiasis, which is dependent upon intestinal eosinophils and suppression of TNF-α