Project description:Previous studies of our group have shown that IL-25 is essential for the resistance to E. caproni infections and the susceptibility of mice relies on the inability of this host species to produce IL-25 in response to infection (14-15). Susceptibility of mice to primary E. caproni infection was associated with low levels of intestinal IL-25 expression, whilst deworming via administration of praziquantel (pzq) was accompanied by a steady increase in IL-25 expression and, in turn, by the onset of a Th2-type response that prevented the establishment of secondary infections (14-15). Although these facts, little is known about the mechanism by which IL-25 generates resistance against intestinal helminths. In the present work, we analyze the changes in the production of proteins induced by IL-25 in the ileum of mice that may be involved in the generation of resistance against intestinal helminths.
Project description:ILC2 cells are a newly described cell type whose biology and contribution to disease are poorly understood. ILC2 cells are activated by allergens, viral infection, and/or epithelial damage via IL-33 and IL-25. ILC2 cells require IL-2, IL-7, IL-25 and IL-33 for their survival and expansion. In mice, ILC2s produce multiple mediators primarily associated with type 2 inflammation (IL-13, IL-5, IL-4, IL-6, IL-9, IL-10, GM-CSF, amphiregulin). ILC2 cells may contribute to the pathology of asthma through multiple mediators that include IL-13-independent pathways. Our goal is to compare transcriptional profiles of IL-33- or IL-25-activated ILC2 cells from blood to characterize these cells and to identify marker(s) that can be utilized to detect them in human tissue.
Project description:The epithelial cell derived cytokines IL-25 and IL-33 can both activate type 2 innate lymphoid cells (ILC2s). It is not known whether the actions of these cytokines on ILC2s are similar or divergent. To investigate this we performed in vitro culture of human ILC2s with a variety of cytokine combinations including IL-2, IL-7, IL-25 and IL-33. Transcriptome profiling of these different condtions allowed us to assess the impact on gene expression of the different treatments. The results show that IL-25 and IL-33 promote divergent gene expression programs indicating that differential expression of these cytokines can cause diverse ILC2 effector function.
Project description:ILC2 cells are a newly described cell type whose biology and contribution to disease are poorly understood. ILC2 cells are activated by allergens, viral infection, and/or epithelial damage via IL-33 and IL-25. ILC2 cells require IL-2, IL-7, IL-25 and IL-33 for their survival and expansion. In mice, ILC2s produce multiple mediators primarily associated with type 2 inflammation (IL-13, IL-5, IL-4, IL-6, IL-9, IL-10, GM-CSF, amphiregulin). ILC2 cells may contribute to the pathology of asthma through multiple mediators that include IL-13-independent pathways. Our goal is to compare transcriptional profiles of IL-33- or IL-25-activated ILC2 cells from blood to characterize these cells and to identify marker(s) that can be utilized to detect them in human tissue. ILC2 cells (Lineage negative, CRTH2+, CD161+, CD127+) were purified from human blood of 5 different donors by flow cytometry. The ILC2 yield ranged from 20,000 to 165,000 cells per donor (0.001-0.008% WBC). Purified ILC2s were expanded in vitro in the presence of IL-2, IL-7, IL-33 and IL-25 (each at 50 ng/ml) for 7-10 days. Expanded cells maintained the ILC2 phenotype (Lineage negative, CRTH2+, CD161+, CD127+). The cells were rested for 2 days in the presence of 1 ng/ml IL-2 and IL-7 and then treated in the presence of 1 ng/ml IL-2 and IL-7 with either media control, IL-25 (50 ng/ml), IL-33 (50 ng/ml), and/or TSLP (50 ng/ml) in combination, for 6 or 24 hours. Whole RNA was isolated via the RNeasy kit (Qiagen). Stratagene Universal Human Reference RNA was used as the reference.
Project description:Cytokines such as TNF-alpha and IL-1beta are known for their contribution to inflammatory processes in liver . In contrast, the cytokine IL-17 has not yet been assigned a role in liver diseases. IL-17 can cooperate with TNF-alpha to induce a synergistic response on several target genes in different cell lines, but no data exist for primary hepatocytes. To enhance our knowledge on the impact of IL-17 alone and combined with TNF-alpha in primary murine hepatocytes a comprehensive microarray study was designed. IL-1beta was included as this cytokine is suggested to act in a similar manner as the combination of TNF-alpha and IL-17, especially with respect to its role in mRNA stabilization. Results: The present microarray analysis demonstrates that primary murine hepatocytes responded to IL-17 stimulation by upregulation of chemokines and genes, which are functionally responsible to increase and sustain inflammation. Cxcl2, Nfkbiz and Zc3h12a were strongly induced, whereas the majority of the genes were only very moderately upregulated. Promoter analysis revealed involvement of NF-kappaB in the activation of many genes. Combined stimulation of TNF-alpha/IL-17 resulted in enhanced induction of gene expression, but significantly synergistic effects could be applied only to a few genes, such as Nfkbiz, Cxcl2, Zc3h12 and Steap4. Comparison of the gene expression profile obtained after stimulation of TNF-alpha/IL-17 versus IL-1 proposed a IL-1beta-like effect of the latter cytokine combination. Moreover, evidence was provided that modulation of mRNA stability may be a major mechanism by which IL-17 regulates gene expression in primary hepatocytes. This assumption was exemplarily proven for Nfkbiz mRNA for the first time in hepatocytes. Our studies also suggest that RNA stability can partially be correlated to the existence of AU rich elements, but further mechanisms like the RNase-activity of the upregulated Zc3h12a have to be considered. Conclusions: Our microarray analysis gives new insights in IL-17 induced gene expression in primary hepatocytes highlighting the crosstalk with the NF-kappaB signalling pathway. Gene expression profile suggests IL-17 a role in sustaining liver inflammatory processes most likely by RNA stabilization. Altogether, our results provide evidence that IL-17 alone and in concert with TNF-alpha may play a role in inflammatory liver diseases. Primary murine hepatocytes of three animals stimulated for 1 or 4h by TNF-alpha, IL-1beta, IL-17 or TNF-alpha followed by IL-17 were used for microarray analysis.
Project description:Aberrant deposition of extracellular matrix (ECM) resulting in dermal fibrosis is a hallmark of systemic sclerosis (SSc). Evidence suggests that dysfunctional SSc keratinocytes may contribute to fibrosis by altering dermal homeostasis. Whether interleukin-25 (IL-25), an IL-17 family member involved in epithelial/mesenchymal/immune cell interplay takes part in skin fibrosis is unknown. Here we address the role of IL-25 in SSc skin fibrosis. Compared to healthy donor (HD), in SSc and scleroderma-like disorders the epidermis expressed significantly lower levels of IL-25. In epidermal equivalents, IL-25 regulated several molecular pathways related to wound healing and ECM remodeling. Compared to control conditioned medium (CM), the CM from IL-25-primed keratinocytes enhanced the production by fibroblasts of matrix metalloproteinase-1 (MMP-1), IL-6, IL-8 (p< 0.05), but not of type-I collagen (Col-I ) nor fibronectin. However, IL- 25 significantly reduced the production of Col-I when applied directly to fibroblasts. The activation of keratinocytes by IL-25 was receptor-dependent and evident after a very short incubation time (10 min), largely mediated by IL-1, suggesting enhanced and specific release of preformed mediators. These results show that IL-25 participates to skin homeostasis and its decreased expression in SSc may contribute to skin fibrosis by favoring ECM deposition over degradation.
Project description:Transcriptional profiling of PNPase KO liver hepatocytes (HepKO) generated from Albumin-Cre/wt (liver-specific) Pnpt1 fl/fl C57BL/6J mice. Samples comparing liver hepatocyte PNPase KO (HepKO) cells to litter-, age-, and sex-matched wildtype hepatocyte control cells. The goal of this experiment was to determine effects of PNPase loss on the total RNA transcriptome under physiologic in vivo conditions.