Interleukin-19 impairment in active Crohn's disease patients

Effect of Microbiota in the Development of Breast Cancer

Breast cancer is the most frequent cancer among women and causes the greatest number of cancer-related death among women all over the world. It approximately accounts for 15% of all cancer death. The human microbiota is the term applied to the aggregate of microbes that live in different habitats of living organisms 'bodies, including the gut, skin, vagina, and mouth, as well as nose, conjunctiva, pharynx, and urethra, among others. Increasing evidence is pointing to the role of the microbiome in the occurrence and development of a variety of cancers. Intestinal microbiome imbalance is related to the occurrence of gastrointestinal tumors, such as esophageal, gastric, colorectal, and gallbladder cancer. The present study aimed to identify the role of microbiota in the development of breast cancer. The women with breast cancer (n=130) in this study were in the age range of 25-75 years. The study was conducted in Kirkuk city of Iraq from September 10, 2019, to March 15, 2020. The control group included 20 women diagnosed with benign breast lesions in the age range 25-75 years, who matched the women in the patient group. Blood samples and breast tissue samples were taken from patients with breast cancer and benign breast lesions. Blood samples were examined through immunological methods, enzyme-linked immunosorbent assay (ELISA) was adopted for the detection of interleukin-19 (IL-19). Breast tissue samples were taken from breast cancer and benign breast lesions patients to isolate and identify bacteria. Based on the obtained results, only 6 out of 30 (20%) cultured breast tissue samples from women with breast cancer showed bacterial growth. In total, 4 (67%) and 2(33%) of these 6 positive cultures were Escherichia coli was and Staphylococcus aureus, respectively, and this relation was statistically significant. However, no bacterial growth was observed on the cultured breast tissue samples taken from women with benign breast lesions. Moreover, the difference between women with a positive and negative result of bacterial culture and stages of breast cancer was statistically non-significant. It is worth mentioning that 50 % of women with breast cancer and bacterial growth were within the age range of 40-49 year. The present study revealed that the difference between women with breast cancer and those with benign breast lesions was statistically highly significant according to the place of residence. In addition, the mean level of IL-19 among women with breast cancer was lower than that in women with benign breast lesions, and this relation was statistically highly significant.

Interleukin-19 enhances cytokine production induced by lipopolysaccharide and inhibits cytokine production induced by polyI:C in BALB/c mice

Interleukin (IL)-19 is a cytokine of the IL-10 family. There are many reports on the involvement of IL-19 in several human diseases. There also are many reports elucidating the role of IL-19 using mouse disease models. Most reports use C57BL/6 mice, whereas few reports use BALB/c mice, in terms of the mouse disease model that the researchers used in the present study. To date, research on the role of IL-19 is diversified, yet some basic mechanisms are still unclear. In this study, we administered lipopolysaccharide (LPS), polyI:C, and CpG to BALB/c mice, measured more than 20 cytokines in the blood and compared them with that of the wild-type and IL-19-deficient (IL-19 KO) mice. LPS is associated with bacterial infection, polyI:C is associated with viral infection, and CpG is associated with both bacterial and viral infections. Among the cytokines measured, the results of experiments using LPS revealed that the production of some cytokines was suppressed in IL-19 KO mice. Interestingly, the experiments using polyI:C revealed that production of some cytokines was enhanced in IL-19 KO mice. However, the experiments using CpG have shown that the production of only one cytokine was enhanced in IL-19 KO mice. These results revealed that cytokine production in the blood was regulated by IL-19, and the type of regulation was dependent on the administered stimulant.

Human Regulatory T Cells From Umbilical Cord Blood Display Increased Repertoire Diversity and Lineage Stability Relative to Adult Peripheral Blood

The human T lymphocyte compartment is highly dynamic over the course of a lifetime. Of the many changes, perhaps most notable is the transition from a predominantly naïve T cell state at birth to the acquisition of antigen-experienced memory and effector subsets following environmental exposures. These phenotypic changes, including the induction of T cell exhaustion and senescence, have the potential to negatively impact efficacy of adoptive T cell therapies (ACT). When considering ACT with CD4+CD25+CD127-/lo regulatory T cells (Tregs) for the induction of immune tolerance, we previously reported ex vivo expanded umbilical cord blood (CB) Tregs remained more naïve, suppressed responder T cells equivalently, and exhibited a more diverse T cell receptor (TCR) repertoire compared to expanded adult peripheral blood (APB) Tregs. Herein, we hypothesized that upon further characterization, we would observe increased lineage heterogeneity and phenotypic diversity in APB Tregs that might negatively impact lineage stability, engraftment capacity, and the potential for Tregs to home to sites of tissue inflammation following ACT. We compared the phenotypic profiles of human Tregs isolated from CB versus the more traditional source, APB. We conducted analysis of fresh and ex vivo expanded Treg subsets at both the single cell (scRNA-seq and flow cytometry) and bulk (microarray and cytokine profiling) levels. Single cell transcriptional profiles of pre-expansion APB Tregs highlighted a cluster of cells that showed increased expression of genes associated with effector and pro-inflammatory phenotypes (CCL5, GZMK, CXCR3, LYAR, and NKG7) with low expression of Treg markers (FOXP3 and IKZF2). CB Tregs were more diverse in TCR repertoire and homogenous in phenotype, and contained fewer effector-like cells in contrast with APB Tregs. Interestingly, expression of canonical Treg markers, such as FOXP3, TIGIT, and IKZF2, were increased in CB CD4+CD127+ conventional T cells (Tconv) compared to APB Tconv, post-expansion, implying perinatal T cells may adopt a default regulatory program. Collectively, these data identify surface markers (namely CXCR3) that could be depleted to improve purity and stability of APB Tregs, and support the use of expanded CB Tregs as a potentially optimal ACT modality for the treatment of autoimmune and inflammatory diseases.

IL-20-Receptor Signaling Delimits IL-17 Production in Psoriatic Inflammation

IL-17 cytokines, in particular IL-17A, are critical effectors in psoriasis. Antibodies that block IL-17A are highly efficacious in treating psoriasis. Likewise, disruption of IL-17 cytokines signaling, such as via the loss of the adaptor CIKS/Act1, ameliorates inflammation in mouse models of psoriasis. IL-17A promotes a cascade of effects, including the robust production of IL-19 in both humans and mice. IL-19, along with IL-20 and IL-24, signal via IL-20 receptors and comprise a subgroup within the IL-10 cytokine family. The role of these three cytokines in psoriasis is unresolved. They have been linked to inflammatory processes, including psoriatic pathology, but these cytokines have also been reported to suppress inflammation in other contexts. In this study, we demonstrate that signaling via IL-20 receptors, including in response to IL-19, delimited aspects of imiquimod-induced psoriatic inflammation. IL-20 receptor signaling suppressed the dermal production of the CCL2 chemokine and thereby reduced CCL-2-driven infiltration of inflammatory cells into the dermis, including IL-17A-producing γδT cells. This constitutes a negative feedback, since IL-17A strongly induces IL-19 in keratinocytes. The effects of IL-17 cytokines in this inflammatory setting are dynamic; they are central to the development of both dermal and epidermal hallmarks of psoriasis but also initiate a path to mitigate inflammatory damage.

The clarified role of interleukin-19 in the inflammatory bowel disease and hypersensitivity: Insights from animal models and humans

The cytokine interleukin-19 (IL-19) is a member of the IL-10 family that includes IL-20, IL-22, IL-24, and IL-26. Previous studies indicated that IL-19 is produced by keratinocytes, epithelial cells, macrophages, and B-cells. Especially, the number of IL-4-producing T cells increased, whereas the number of IFN-γ-producing T cells decreased when naive T cells from healthy people were cultured in the presence of IL-19. There is an increasing body of data demonstrating that IL-19 is associated with the development of type 1 helper T cell-responses, although IL-19 was originally associated with the development of type 2 helper T cell-responses. In this review, we will attempt to discuss current knowledge about the role of IL-19 on several T cell response-mediated inflammatory diseases including inflammatory bowel disease and hypersensitivity.

Interleukin-10 Family Cytokines Immunobiology and Structure

The Interleukin (IL)-10 cytokine family includes IL-10, IL-19, IL-20, IL-22, IL-24, and IL-26, which are considered as Class 2α-helical cytokines. IL-10 is the most important cytokine in suppressing pro-inflammatory responses in all kinds of autoimmune diseases and limiting excessive immune responses. Due to protein structure homology and shared usage of receptor complexes as well as downstream signaling pathway, other IL-10 family cytokines also show indispensable functions in immune regulation, tissue homeostasis, and host defense. In this review, we focus on immune functions and structures of different cytokines in this family and try to better understand how their molecular mechanisms connect to their biological functions. The molecular details regarding their actions also provide useful information in developing candidate immune therapy reagents for a variety of diseases.

The Interleukin-20 Cytokines in Intestinal Diseases

Autoimmune/inflammatory intestinal diseases, such as Crohn’s disease and ulcerative colitis, infectious gastrointestinal diseases, and gastrointestinal cancers, such as colorectal cancer, are worldwide a significant health problem. Intercellular communication and direct contact with the environment as the microbiota colonizes the gastrointestinal surface facilitates these diseases. Cytokines mediate the intercellular communication to maintain the equilibrium between host and environment and to regulate immune responses. One cytokine family that exchange information between immune cells and epithelial cells is the IL-20 cytokine family which includes the cytokines IL-19, IL-20, IL-22, IL-24, and IL-26. These cytokines share common receptor subunits and signaling pathways. IL-22 is the most intensively studied cytokine within this family in contexts of gastrointestinal disease, but the importance of other family members is more and more appreciated. In this review, the potential function of IL-20 cytokines concerning gastrointestinal conditions is discussed.

Inverse Association Between Circulating Monocyte-Platelet Complexes and Inflammation in Ulcerative Colitis Patients

BACKGROUND

Circulating monocytes from active ulcerative colitis (UC) patients produced high levels of tumor necrosis factor-alpha(TNFα) and interleukin(IL)-6 after Toll-like receptors (TLR) stimulation. Since platelets (PLT) can bind to leukocytes, thereby decreasing inflammatory cytokine production, UC patients may exhibit different levels of monocyte-platelet complexes depending on disease activity.

METHODS

We compared among healthy donors, active (onset flare and relapse), and inactive UC patients the presence of circulating monocyte-platelet complexes (CD14+PLT+) and membrane CD162 expression by flow cytometry. Lipopolysaccharide- binding protein, TNFα, and IL-10 were compared by ELISA. Binding of CD14+PLT+ to human umbilical vein endothelial cells (HUVECs) were analyzed by immunofluorescence.

RESULTS

Onset flare UC patients had the lowest levels of CD14+PLT+. Membrane CD162, crucial for the PLT binding, was downregulated only on monocytes from onset flare UC patients. Membrane CD162 expression on CD14+ cells inversely correlated with lipopolysaccharide binding protein levels. As an expected consequence, more CD14+PLT+ than CD14+PLT- from onset flare UC patients bound to activated HUVECs. TNFα tended to negatively correlate with CD14+PLT+ in relapse and inactive UC patients, whereas IL-10 positively correlated with CD14+PLT+ in all UC patients (r = -0.43, P = 0.1 and r = 0.61, P = 0.01, respectively). The anti-inflammatory role of PLT binding to monocytes was confirmed in cocultures of PLT and monocytes. These cocultures increased the percentage of CD14+PLT+ and IL-10 production, and decreased TNFα production. These anti-inflammatory effects were abolished when we blocked the binding of PLT with neutralizing anti-CD62P antibody.

CONCLUSIONS

Decreased CD162 expression associated with endotoxemia reduced the binding of PLT to monocytes through membrane CD162-CD62P, favoring the inflammatory response of onset flare UC patients.

The Stimulation of Macrophages with TLR Ligands Supports Increased IL-19 Expression in Inflammatory Bowel Disease Patients and in Colitis Models

IL-19, a member of the IL-10 cytokine family that signals through the IL-20 receptor type I (IL-20Rα:IL-20Rβ), is a cytokine whose function is not completely known. In this article, we show that the expression of IL19 in biopsies of patients with active ulcerative colitis was increased compared with patients with quiescent ulcerative colitis and that colitis was attenuated in IL-19-deficient mice. The disruption of the epithelial barrier with dextran sodium sulfate leads to increased IL-19 expression. Attenuated colitis in IL-19-deficient animals was associated with reduced numbers of IL-6-producing macrophages in the inflamed colonic lamina propria. Microbial-driven expression of IL-19 by intestinal macrophages may contribute to the pathogenesis of inflammatory bowel disease.

MicroRNAs: New regulators of IL-22

Interleukin-22 (IL-22) is a cytokine that belongs to the IL-10 family of interleukins. It can be produced by T helper 22 (Th22) cells, T helper 1 (Th1) cells, T helper 17 (Th17) cells, natural killer 22 (NK22) cells, natural killer T (NKT) cells, innate lymphoid cells (ILCs), and γδ T cells. IL-22 acts via binding to a heterodimeric transmembrane receptor complex that consists of IL-22R1 and IL-10R2 and mainly contributes to the tissue repair and host defense. Transcription factors such as retinoid orphan receptor γt (RORγt) and signal transducer and activator of transcription 3 (STAT3), have been reported to play important roles in regulation of IL-22 expression. Recently, it has been demonstrated in several studies that microRNAs (miRNAs) potently regulate expression of interleukins, including production of IL-22. Here, we review current knowledge about regulators of IL-22 expression with a particular emphasis on the role of miRNAs.

Altered gp130 signalling ameliorates experimental colitis via myeloid cell-specific STAT3 activation and myeloid-derived suppressor cells

STAT3 regulates the expansion of myeloid-derived suppressor cells (MDSCs) during inflammation, infection and cancer. Hyperactivation of STAT3 in gp130^757F/F mice is associated with protection from experimental colitis. This study determined mechanisms for this protection and compared this to mice with myeloid-specific STAT3-deficiency (LysMcre/STAT3^flox; gp130^757F/F LysMcre/STAT3^flox). Acute and chronic colitis was induced and colons were removed for histological, mRNA and protein analysis. Cell populations from spleen, mesenteric lymph node and colon were analyzed for different myeloid cell populations using flow cytometry. Functions of MDSCs and LPS-stimulated peritoneal macrophages were further characterized by in vitro and in vivo assays. Here we show that the resistance to experimental colitis in gp130^757F/F mice is via myeloid-cell specific STAT3 activation, MDSC expansion and increased production of suppressive and protective cytokines.

Interleukin 19 reduces inflammation in chemically induced experimental colitis

Inflammatory bowel disease results from chronic dysregulation of the mucosal immune system and aberrant activation of both the innate and adaptive immune responses. Interleukin (IL)-19, a member of the IL-10 family, functions as an anti-inflammatory cytokine. Here, we investigated the contribution of IL-19 to intestinal inflammation in a model of T cell-mediated colitis in mice. Inflammatory responses in IL-19-deficient mice were assessed using the 2,4,6-trinitrobenzene sulfonic acid (TNBS) model of acute colitis. IL-19 deficiency aggravated TNBS-induced colitis and compromised intestinal recovery in mice. Additionally, the exacerbation of TNBS-induced colonic inflammation following genetic ablation of IL-19 was accompanied by increased production of interferon-gamma, IL-12 (p40), IL-17, IL-22, and IL-33, and decreased production of IL-4. Moreover, the exacerbation of colitis following IL-19 knockout was also accompanied by increased production of CXCL1, G-CSF and CCL5. Using this model of induced colitis, our results revealed the immunopathological relevance of IL-19 as an anti-inflammatory cytokine in intestinal inflammation in mice.

Toll-like receptor 2 and 4 induced interleukin-19 dampens immune reactions and associates inversely with spondyloarthritis disease activity

Spondyloarthritis (SpA) is a group of immune mediated inflammatory diseases affecting joints, gut, skin and entheses. The inflammatory process involves activation of Toll-like receptor (TLR)-2 and TLR-4 and production of cytokines and chemokines such as monocyte chemoattractant protein 1 (CCL2/MCP-1). This proinflammatory chemokine recruits monocytes to sites of inflammation and is central in the development of several immune-mediated inflammatory diseases. Interleukin (IL)-19 is a member of the IL-10 family of cytokines. IL-19-deficient mice are more susceptible to innate-mediated colitis and develop more severe inflammation in response to injury. In this work, we studied inducers of IL-19 production and effect of IL-19 on the production of CCL2/MCP-1 and proinflammatory cytokines in peripheral blood mononuclear cells (PBMCs) from healthy controls (HCs) and in PBMCs and synovial fluid mononuclear cells (SFMCs) from SpA patients. Further, we measured IL-19 in plasma from HCs and in plasma and synovial fluid from SpA patients. Constitutive IL-19 expression was present in both PBMCs and SFMCs and the secretion of IL-19 was increased by TLR-2 and TLR-4 ligands. Neutralizing IL-19 in HC PBMCs and SpA SFMCs resulted in increased production of CCL-2/MCP-1. IL-19 concentrations were decreased in synovial fluid compared with plasma and associated inversely with disease activity in SpA. SpA SFMCs produced less IL-19 in response to LPS compared with HC PBMCs. These findings indicate that IL-19 production is diminished in SpA. Taken together, impaired IL-19 control of the innate immune system might be involved in the pathogenesis of SpA.

Insights from GWAS: emerging landscape of mechanisms underlying complex trait disease

BACKGROUND

There are now over 2000 loci in the human genome where genome wide association studies (GWAS) have found one or more SNPs to be associated with altered risk of a complex trait disease. At each of these loci, there must be some molecular level mechanism relevant to the disease. What are these mechanisms and how do they contribute to disease?

RESULTS

Here we consider the roles of three primary mechanism classes: changes that directly alter protein function (missense SNPs), changes that alter transcript abundance as a consequence of variants close-by in sequence, and changes that affect splicing. Missense SNPs are divided into those predicted to have a high impact on in vivo protein function, and those with a low impact. Splicing is divided into SNPs with a direct impact on splice sites, and those with a predicted effect on auxiliary splicing signals. The analysis was based on associations found for seven complex trait diseases in the classic Wellcome Trust Case Control Consortium (WTCCC1) GWA study and subsequent studies and meta-analyses, collected from the GWAS catalog. Linkage disequilibrium information was used to identify possible candidate SNPs for involvement in disease mechanism in each of the 356 loci associated with these seven diseases. With the parameters used, we find that 76% of loci have at least of these mechanisms. Overall, except for the low incidence of direct impact on splice sites, the mechanisms are found at similar frequencies, with changes in transcript abundance the most common. But the distribution of mechanisms over diseases varies markedly, as does the fraction of loci with assigned mechanisms. Many of the implicated proteins have previously been suggested as relevant, but the specific mechanism assignments are new. In addition, a number of new disease relevant proteins are proposed.

CONCLUSIONS

The high fraction of GWAS loci with proposed mechanisms suggests that these classes of mechanism play a major role. Other mechanism types, such as variants affecting expression of genes remote in the DNA sequence, will contribute in other loci. Each of the identified putative mechanisms provides a hypothesis for further investigation.

TFF2 deficiency exacerbates weight loss and alters immune cell and cytokine profiles in DSS colitis, and this cannot be rescued by wild-type bone marrow

The trefoil factor TFF2 is a member of a tripartite family of small proteins that is produced by the stomach and the colon. Recombinant TFF2, when applied intrarectally in a rodent model of hapten colitis, hastens mucosal healing and reduces inflammatory indexes. Additionally, TFF2 is expressed in immune organs, supporting a potential immunomodulatory and reparative role in the bowel. In this study we confirm that TFF2 is expressed in the colon and is specifically enriched in epithelial cells relative to colonic leukocytes. TFF2-deficient, but not TFF1-deficient, mice exhibit a more severe response to acute or chronic dextran sulfate (DSS)-induced colitis that correlates with a 50% loss of expression of TFF3, the principal colonic trefoil. In addition, the response to acute colitis is associated with altered expression of IL-6 and IL-33, but not other inflammatory cytokines. While TFF2 can reduce macrophage responsiveness and block inflammatory cell recruitment to the colon, the major role in limiting the susceptibility to acute colitis appears to be maintenance of barrier function. Bone marrow transfer experiments demonstrate that leukocyte expression of TFF2 is not sufficient for prevention of colitis induction but, rather, that the gastrointestinal epithelium is the primary source of TFF2. Together, these findings illustrate that epithelial TFF2 is an important endogenous regulator of gut mucosal homeostasis that can modulate immune and epithelial compartments. Because of its extreme stability, even in the corrosive gut lumen, TFF2 is an attractive candidate as an oral therapeutic scaffold for future drug development in the treatment of inflammatory bowel disease.