•Polarization of cells dramatically increases cytokine secretion in bronchial epithelial cells.•CFTR F508del mutation itself is sufficient to significantly alter the epigenome and transcriptome of ...epithelial cells.•The F508del mutation is closely associated with immunity-related pathways in the epithelial cells in the absence of infection.•These data may serve as epithelial biomarkers for CFTR mRNA therapies.
Cystic fibrosis (CF) is characterized by chronic inflammation and excessive cytokines secretion in the lung. Isogenic human CF bronchial epithelial (CFBE41o-) cell lines stably expressing wt-CFTR (WTBE) or F508del mutant (CFBE) are widely used tools in understanding responses to stimuli or drugs and CF pathogenesis in vitro. However, the intrinsic cellular differences in culture are unknown.
We performed integrative analyses of these isogenic cells at the protein, mRNA, and chromatin levels in the submerged and air-liquid interface (ALI) conditions to determine cell intrinsic effects of mutant versus complemented CFTR expression.
CFBE and WTBE cells displayed different cytokine secretion patterns, including IL-6, IL-8, CXCL1, CXCL10, and CCL5. The ALI culture dramatically increased cytokine secretion in both cells. Assay for transposase-accessible chromatin using sequencing (ATAC-seq) result showed different chromatin landscapes upon polarization and CFBE cells, compared to WTBE cells, exhibited higher genome-wide chromatin accessibility under both culture methods. At the transcriptome level, differentially expressed genes identified by mRNA sequencing between two cell lines were highly concentrated in immunity-related pathways.
This multilayered study shows that expression of wild-type CFTR has an epithelial cell intrinsic effect on the cell's epigenome and transcriptome particularly in immunity relevant activities. These data will serve as a resource for the CF community and may serve as epithelial biomarkers for CFTR mRNA therapy.
Th17 cytokines and mucosal immunity Dubin, Patricia J; Kolls, Jay K
Immunological reviews,
December 2008, Volume:
226, Issue:
1
Journal Article
Peer reviewed
The T-helper 17 (Th17) lineage is a recently described subset of memory T cells that is characterized by its CD4⁺ status and its ability to make a constellation of cytokines including interleukin-17A ...(IL-17A), IL-17F, IL-22, and, in humans, IL-26. Although most extensively described in the autoimmunity literature, there is growing evidence that the Th17 lineage plays a significant role in mediating host mucosal immunity to a number of pulmonary pathogens. This review highlights our current understanding of the role of the Th17 lineage and Th17 cytokines in mediating mucosal immunity to both pulmonary and gastrointestinal pathogens. While we have the strongest evidence that the Th17 lineage is centrally involved in mediating the host response to Gram-negative extracellular pulmonary pathogens, this literature is rapidly evolving and demonstrates a central role for Th17 cytokines both in primary infection and in recall responses seen in vaccine studies. In this review, we summarize the current state of this literature and present possible applications of Th17-targeted immunotherapy in the treatment and prevention of infection.
T helper type 17 (TH17) cells are highly proinflammatory effector T cells that are characterized by the production of high amounts of IL-17A, IL-17F, IL-21, and IL-22. Furthermore, TH17 cells have ...been associated with a number of autoimmune diseases. However, it is not clear whether TH17 cells can also serve as effective helper cells. Here we show that TH17 cells can function as B-cell helpers in that they not only induce a strong proliferative response of B cells in vitro but also trigger antibody production with class switch recombination in vivo. Transfer of TH17 cells into WT or T-cell receptor α–deficient mice, which lack endogenous T cells, induces a pronounced antibody response with preferential isotype class switching to IgG1, IgG2a, IgG2b, and IgG3, as well as the formation of germinal centers. Conversely, blockade of IL-17 signaling results in a significant reduction in both number and size of germinal centers. Whereas IL-21 is known to help B cells, IL-17 on its own drives B cells to undergo preferential isotype class switching to IgG2a and IgG3 subtypes. These observations provide insights into the unappreciated role of TH17 cells and their signature cytokines in mediating B-cell differentiation and class switch recombination.
Mucosal Immunity in Cystic Fibrosis Bojanowski, Christine M; Lu, Shiping; Kolls, Jay K
The Journal of immunology (1950),
12/2021, Volume:
207, Issue:
12
Journal Article
Peer reviewed
Open access
The highly complex and variable genotype-phenotype relationships observed in cystic fibrosis (CF) have been an area of growing interest since the discovery of the CF transmembrane conductance ...regulator (
) gene >30 y ago. The consistently observed excessive, yet ineffective, activation of both the innate and adaptive host immune systems and the establishment of chronic infections within the lung, leading to destruction and functional decline, remain the primary causes of morbidity and mortality in CF. The fact that both inflammation and pathogenic bacteria persist despite the introduction of modulator therapies targeting the defective protein, CFTR, highlights that we still have much to discover regarding mucosal immunity determinants in CF. Gene modifier studies have overwhelmingly implicated immune genes in the pulmonary phenotype of the disease. In this context, we aim to review recent advances in our understanding of the innate and adaptive immune systems in CF lung disease.
Review focuses on the role of STAT3, SFB, and Ahr in Th17 differentiation, as well as innate sources of Th17 cytokines.
Th17 cells contribute to mucosal immunity by stimulating epithelial cells to ...induce antimicrobial peptides, granulopoiesis, neutrophil recruitment, and tissue repair. Recent studies have identified important roles for commensal microbiota and Ahr ligands in stabilizing Th17 gene expression in vivo, linking environmental cues to CD4 T cell polarization. Epigenetic changes that occur during the transition from naïve to effector Th17 cells increase the accessibility of il17a, il17f, and il22 loci to transcription factors. In addition, Th17 cells maintain the potential for expressing T‐bet, Foxp3, or GATA‐binding protein‐3, explaining their plastic nature under various cytokine microenvironments. Although CD4 T cells are major sources of IL‐17 and IL‐22, innate cell populations, including γδ T cells, NK cells, and lymphoid tissue‐inducer cells, are early sources of these cytokines during IL‐23‐driven responses. Epithelial cells and fibroblasts are important cellular targets for IL‐17 in vivo; however, recent data suggest that macrophages and B cells are also stimulated directly by IL‐17. Thus, Th17 cells interact with multiple populations to facilitate protection against intracellular and extracellular pathogens.
Although anticapsular antibodies confer serotype-specific immunity to pneumococci, children increase their ability to clear colonization before these antibodies appear, suggesting involvement of ...other mechanisms. We previously reported that intranasal immunization of mice with pneumococci confers CD4+ T cell-dependent, antibody- and serotype-independent protection against colonization. Here we show that this immunity, rather than preventing initiation of carriage, accelerates clearance over several days, accompanied by neutrophilic infiltration of the nasopharyngeal mucosa. Adoptive transfer of immune CD4+ T cells was sufficient to confer immunity to naïve RAG1(-/-) mice. A critical role of interleukin (IL)-17A was demonstrated: mice lacking interferon-gamma or IL-4 were protected, but not mice lacking IL-17A receptor or mice with neutrophil depletion. In vitro expression of IL-17A in response to pneumococci was assayed: lymphoid tissue from vaccinated mice expressed significantly more IL-17A than controls, and IL-17A expression from peripheral blood samples from immunized mice predicted protection in vivo. IL-17A was elicited by pneumococcal stimulation of tonsillar cells of children or adult blood but not cord blood. IL-17A increased pneumococcal killing by human neutrophils both in the absence and in the presence of antibodies and complement. We conclude that IL-17A mediates pneumococcal immunity in mice and probably in humans; its elicitation in vitro could help in the development of candidate pneumococcal vaccines.
The absent in melanoma 2 (AIM2) inflammasome plays an important role in many viral and bacterial infections, but very little is known about its role in RNA virus infection, including influenza A ...virus (IAV). In this study, we have designed in vivo and in vitro studies to determine the role of AIM2 in infections with lethal doses of IAVs A/PR8/34 and A/California/07/09. In wild-type mice, IAV infection enhanced AIM2 expression, induced dsDNA release, and stimulated caspase-1 activation and release of cleaved IL-1β in the lung, which was significantly reduced in AIM2-deficient mice. Interestingly, AIM2 deficiency did not affect the transcription of caspase-1 and IL-1β. In addition, AIM2-deficient mice exhibited attenuated lung injury and significantly improved survival against IAV challenges, but did not alter viral burden in the lung. However, AIM2 deficiency did not seem to affect adaptive immune response against IAV infections. Furthermore, experiments with AIM2-specific small interfering RNA-treated and AIM2-deficient human and mouse lung alveolar macrophages and type II cells indicated a macrophage-specific function of AIM2 in regulation of IAV-stimulated proinflammatory response. Collectively, our results demonstrate that influenza infection activates the AIM2 inflammasome, which plays a critical role in IAV-induced lung injury and mortality. AIM2 might serve as a therapeutic target for combating influenza-associated morbidity and mortality without compromising the host antiviral responses.
T-helper cells that produce IL-17 are recognized as a significant subset within cell-mediated adaptive immunity. These cells are implicated in both the pathology of inflammatory disorders as well as ...the clearance of extracellular infections and the maintenance of the microbiota. However, the dynamic nature of this cell type has created controversy in understanding Th17 induction as well as Th17 phenotyping, since these cells may switch from Th17 to Treg or Th17 to Th1 cytokine profiles under certain conditions. This review highlights recent advances in Th17 cells in understanding their role in commensal regulation, sex difference in immune outcomes and the immunology of pregnancy, as well as inventive experimental models that have allowed for an increased understanding of Th17 regulation and induction.
Interleukin (IL)-17-producing T helper cells (T(H)17) are a recently identified CD4(+) T cell subset distinct from T helper type 1 (T(H)1) and T helper type 2 (T(H)2) cells. T(H)17 cells can drive ...antigen-specific autoimmune diseases and are considered the main population of pathogenic T cells driving experimental autoimmune encephalomyelitis (EAE), the mouse model for multiple sclerosis. The factors that are needed for the generation of T(H)17 cells have been well characterized. However, where and how the immune system controls T(H)17 cells in vivo remains unclear. Here, by using a model of tolerance induced by CD3-specific antibody, a model of sepsis and influenza A viral infection (H1N1), we show that pro-inflammatory T(H)17 cells can be redirected to and controlled in the small intestine. T(H)17-specific IL-17A secretion induced expression of the chemokine CCL20 in the small intestine, facilitating the migration of these cells specifically to the small intestine via the CCR6/CCL20 axis. Moreover, we found that T(H)17 cells are controlled by two different mechanisms in the small intestine: first, they are eliminated via the intestinal lumen; second, pro-inflammatory T(H)17 cells simultaneously acquire a regulatory phenotype with in vitro and in vivo immune-suppressive properties (rT(H)17). These results identify mechanisms limiting T(H)17 cell pathogenicity and implicate the gastrointestinal tract as a site for control of T(H)17 cells.
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