pIgR Expression Research Articles

Malondialdehyde-Acetaldehyde Adduct Formation Decreases Immunoglobulin A Transport across Airway Epithelium in Smokers Who Abuse Alcohol

Alcohol misuse and smoking are risk factors for pneumonia, yet the impact of combined cigarette smoke and alcohol on pneumonia remains understudied. Smokers who misuse alcohol form lung malondialdehyde-acetaldehyde (MAA) protein adducts and have decreased levels of anti-MAA secretory IgA (sIgA). Transforming growth factor-β (TGF-β) down-regulates polymeric Ig receptor (pIgR) on mucosal epithelium, resulting in decreased sIgA transcytosis to the mucosa. It is hypothesized that MAA-adducted lung protein increases TGF-β, preventing expression of epithelial cell pIgR and decreasing sIgA. Cigarette smoke and alcohol co-exposure on sIgA and TGF-β in human bronchoalveolar lavage fluid and in mice instilled with MAA-adducted surfactant protein D (SPD-MAA) were studied herein. Human bronchial epithelial cells (HBECs) and mouse tracheal epithelial cells were treated with SPD-MAA and sIgA and TGF-β was measured. Decreased sIgA and increased TGF-β were observed in bronchoalveolar lavage from combined alcohol and smoking groups in humans and mice. CD204 (MAA receptor) knockout mice showed no changes in sIgA. SPD-MAA decreased pIgR in HBECs. Conversely, SPD-MAA stimulated TGF-β release in both HBECs and mouse tracheal epithelial cells, but not in CD204knockout mice. SPD-MAA stimulated TGF-β in alveolar macrophage cells. These data show thatMAA-adducted surfactant protein stimulates lung epithelial cell TGF-β, down-regulates pIgR, anddecreases sIgA transcytosis. These data provide a mechanism for the decreased levels of sIgA observed in smokers who misuse alcohol.

Porcine Milk-Derived Small Extracellular Vesicles Promote Intestinal Immunoglobulin Production through pIgR.

Simple SummaryAs the irreplaceable nutrient source for young mammals, milk has a number of biological functions. Milk derived extracellular vesicles are a recently discovered component of milk and have potential regulatory effects on intestinal health and immunity. In this study, in vivo and in vitro experiments were performed to examine the effects of porcine milk small extracellular vesicles (PM-sEVs) on intestinal immunity. As a result, PM-sEVs promoted intestinal secretory immunoglobulin A (SIgA) levels, and increased the expression levels of the polymeric immunoglobulin receptor (pIgR) both in mice and piglet. We identified circ-XPO4 in PM-sEVs as a crucial circRNA, which promotes the expression of pIgR via the suppression of miR-221-5p in the intestinal cell. In conclusion, our research provides a new understanding of the nutritional physiology of porcine milk in intestinal immunity.Secretory immunoglobulin A (SIgA) plays an important role in gut acquired immunity and mucosal homeostasis. Breast milk is the irreplaceable nutritional source for mammals after birth. Current studies have shown the potential functional role of milk-derived small extracellular vesicles (sEVs) and their RNAs cargo in intestinal health and immune regulation. However, there is a lack of studies to demonstrate how milk-derived sEVs affect intestinal immunity in recipient. In this study, through in vivo experiments, we found that porcine milk small extracellular vesicles (PM-sEVs) promoted intestinal SIgA levels, and increased the expression levels of polymeric immunoglobulin receptor (pIgR) both in mice and piglet. We examined the mechanism of how PM-sEVs increased the expression level of pIgR in vitro by using a porcine small intestine epithelial cell line (IPEC-J2). Through bioinformatics analysis, dual-luciferase reporter assays, and overexpression or knockdown of the corresponding non-coding RNAs, we identified circ-XPO4 in PM-sEVs as a crucial circRNA, which leads to the expression of pIgR via the suppression of miR-221-5p in intestinal cells. Importantly, we also observed that oral administration of PM-sEVs increased the level of circ-XPO4 and decreased the level of miR-221-5p in small intestine of piglets, indicating that circRNAs in milk-derived sEVs act as sponge for miRNAs in recipients. This study, for the first time, reveals that PM-sEVs have a capacity to stimulate intestinal SIgA production by delivering circRNAs to receptors and sponging the recipient’s original miRNAs, and also provides valuable data for insight into the role and mechanism of animal milk sEVs in intestinal immunity.

The effect of delayed feeding post-hatch on caeca development in broiler chickens

ABSTRACT 1. Broiler chicks are frequently deprived of food up to 72 h due to uneven hatching rates, management procedures and transportation to farms. Little is known about the effect of delayed feeding due to extended hatching times on the early neonatal development of the caeca. Therefore, the objective of this study was to investigate the developmental changes and effects of a 48-h delay in feed access immediately post-hatch (PH) on the caeca. 2. After hatch, birds (Ross 708) were randomly divided into two treatment groups (n = 6 battery pen/treatment). One group (early fed; EF) received feed and water immediately after hatch, while the second group (late fed; LF) had access to water but had delayed access to feed for 48 h. Contents averaging across all regions of the caeca were collected for mRNA expression as well as for histological analysis at −48, 0, 4 h PH and then at 1, 2, 3, 4, 6, 8, 10, 12 and 14 days PH. 3. Expression of MCT-1 (a nutrient transporter), Cox7A2 (related to mitochondrial function) IgA, pIgR, and ChIL-8 (immune function) genes was affected by delayed access to feed that was dependent by the time PH. Expression of immune and gut barrier function-related genes (LEAP2 and MUC2, respectively) was increased in LF group. There was no effect of feed delay on expression of genes related to mitochondrial functions in the caeca, although developmental changes were observed (ATP5F1B, Cox4|1). Caecal mucus and muscle thickness were affected by delayed access to feed during caeca development. 4. The data suggested a limited effect of delayed feed access PH on the developmental changes in caecal functions. However, the caeca seemed to be relatively resistant to delayed access to feed early PH, with only a few genes affected.

IL-17A or IL-17F is sufficient to maintain innate response and control of H. pylori immunopathogenesis

Abstract Interleukin-17 receptor (IL-17R) signaling is required for control of many extracellular pathogens due to its impact on neutrophil recruitment and antimicrobial responses. Infection with the extracellular pathogen Helicobacter pylori results in Th1 and Th17 cell activation and a chronic inflammatory process which can lead to adverse outcomes such as gastric cancer. Previously, we identified IL-17RA as a requirement for the recruitment of neutrophils. Surprisingly, H. pylori infected IL-17RA−/− mice had significantly more chronic inflammation than H. pylori infected WT mice. In the current study, in vitro human epithelial cell cultures and in vivo mouse models were used to investigate differential roles for IL-17A, IL-17F and IL-17A/F during H. pylori infection. The data indicate generally that epithelial cells responded to IL-17A or IL-17A/F better than IL-17F. Increased gene expression of some factors, such as Cxcl8, required a co-stimulus such as H. pylori, TNF or IL-22 in epithelial cells, but expression of Pigr and Nox1 were induced by IL-17A alone. In vivo deficiencies of IL-17A or IL-17F alone did not significantly change the immunopathological response to H. pylori, but if both cytokines were absent, a hyperinflammatory lymphocytic response developed similar to what was observed in IL-17RA−/− mice. These data imply that IL-17A and IL-17F may have some overlapping role or compensatory roles in maintenance of the gastric mucosal response to infection which is required for preventing immunopathology.

High dose lithium chloride causes colitis through activating F4/80 positive macrophages and inhibiting expression of Pigr and Claudin-15 in the colon of mice

ObjectiveLithium chloride (LiCl) was a mood stabilizer for bipolar affective disorders and it could activate Wnt/β-catenin signaling pathway both in vivo and in vitro. Colon is one of a very susceptible tissues to Wnt signaling pathway, and so it would be very essential to explore the toxic effect of a high dose of LiCl on colon. MethodsC57BL/6 mice were injected intraperitoneally with 200 mg/kg LiCl one dose a day for 5 days to activate Wnt signal pathway in intestines. H&E staining was used to assess the colonic tissues of mice treated with high dose of LiCl. The expression of inflammation-associated genes and tight junction-associated genes in colons was measured using qPCR, Western blot and immunostaining methods. The gut microbiome was tested through 16S rDNA gene analysis. ResultsThe differentiation of enteroendocrine cells in colon was inhibited by treatment of 200 mg/kg LiCl. The F4/80 positive macrophages in colon were activated by high dose of LiCl, and migrated from the submucosa to the lamina propria. The expression of pro-inflammatory genes TNFα and IL-1β was increased in the colon of high dose of LiCl treated mice. Clostridium_sp_k4410MGS_306 and Prevotellaceae_UCG_001 were specific and predominant for the high dose of LiCl treated mice. The expression of IgA coding genes, Pigr and Claudin-15 was significantly decreased in the colon tissues of the high dose of LiCl treated mice. Conclusion200 mg/kg LiCl might cause the inflammation in colon of mice through activating F4/80 positive macrophages and inhibiting the expression of IgA coding genes in plasma cells and the expression of Pigr and Claudin-15 in colonic epithelial cells, providing evidences for the toxic effects of high dose of LiCl on colon.

Upregulation of polymeric immunoglobulin receptor expression in flounder (Paralichthys olivaceus) gill cells by cytokine tumor necrosis factor-α via activating PI3K and NF-κB signaling pathways

The polymeric immunoglobulin receptor (pIgR) transports secretory immunoglobulins across mucosal epithelial cells into external secretions, playing critical roles in mucosal surface defenses, but the regulation mechanism of pIgR expression is not clarified in teleost fish. In this study, the dynamic changes of flounder (Paralichthys olivaceus) pIgR (fpIgR) and pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) mRNA expression in mucosal tissues were first analyzed post inactivated Vibrio anguillarum immunization, and increased production of TNF-α was found to correlate with increased expression of fpIgR. To determine that cytokine TNF-α influenced fpIgR expression, following confirming that natural fpIgR expressed on flounder gill (FG) cells, FG cells were incubated with various concentrations of recombinant TNF-α for different time, the results showed that the expressions of fpIgR were significantly upregulated at gene and protein levels in a dose-dependent and time-dependent manner, and similar change trend was observed for free secretory component (SC) secreted by fpIgR into the culture supernatant. After FG cells were treated with TNF-α, specific phosphoinositide 3-kinase (PI3K) inhibitor wortmannin, nuclear factor kappa-B (NF-κB) inhibitor Bay11−7082, and the mixtures of TNF-α and wortmannin / Bay11−7082 respectively, the fpIgR protein and mRNA levels, together with SC secretion, obviously decreased in wortmannin- and Bay11−7082-treated cells compared with the untreated control, and cotreatment with wortmannin / Bay11−7082 plus TNF-α resulted in lower expression compared with that upon treatment with TNF-α alone, indicating that the inhibition of PI3K and NF-κB both blocked the ability of TNF-α to increase cellular fpIgR and SC levels. Furthermore, the gene expressions of PI3K and NF-κB were upregulated and present a tendency to increase first and then decrease after TNF-α treatment of FG cells; However, the expression of PI3K mRNA was inhibited significantly by wortmannin but not by Bay11−7082, and the expression of NF-κB mRNA was suppressed obviously by Bay11−7082 but not by wortmannin, suggesting that inhibition of PI3K or NF-κB had no influence on each other. All these results collectively revealed that TNF-α could transcriptionally upregulate fpIgR expression and SC production, and this TNF-α-induced pIgR expression was regulated by complex mechanisms that involved PI3K and NF-κB signaling pathways, which provided evidences for pro-inflammatory cytokine TNF-α acting as a regulator in pIgR expression and better understanding of regulation mechanism of pIgR expression in teleost fish.

Rifaximin as a Potential Treatment for IgA Nephropathy in a Humanized Mice Model.

: BackgroundIgA Nephropathy (IgAN) is the most common glomerulonephritis worldwide, characterized by the mesangial deposition of abnormally glycosylated IgA1 (Gd-IgA). The production of Gd-IgA occurs in mucose-associated lymphoid tissue (MALT). The microbiota plays a role in MALT modulation. Rifaximin (NORMIX®), a non-absorbable oral antibiotic, induces positive modulation of the gut microbiota, favoring the growth of bacteria beneficial to the host. Here, we evaluate the effect of rifaximin on a humanized mice model of IgAN (α1KI-CD89Tg). Methods: The α1KI-CD89Tg mice were treated by the vehicle (olive oil) or rifaximin (NORMIX®). Serum levels of hIgA, hIgA1–sCD89, and mIgG–hIgA1 immune complexes were determined. Glomerular hIgA1 deposit and CD11b+ cells recruitment were revealed using confocal microscopy. Furthermore, the mRNA of the B-Cell Activating Factor (BAFF), polymeric immunoglobulin receptor (pIgR), and Tumor Necrosing Factor-α (TNF-α) in gut samples were detected by qPCR. Results: Rifaximin treatment decreased the urinary protein-to-creatinine ratio, serum levels of hIgA1–sCD89 and mIgG–hIgA1 complexes, hIgA1 glomerular deposition, and CD11b+ cell infiltration. Moreover, rifaximin treatment decreased significantly BAFF, pIgR, and TNF-α mRNA expression. Conclusions: Rifaximin decreased the IgAN symptoms observed in α1KI-CD89Tg mice, suggesting a possible role for it in the treatment of the disease.

DUSP16 IS A NOVEL IBD GENE IMPLICATED IN THE REGULATION OF DIFFERENTIATION AND HOMEOSTASIS OF INTESTINAL EPITHELIAL CELLS

Inflammatory bowel disease (IBD) are chronic inflammatory diseases including Crohn’s disease (CD) and ulcerative colitis (UC). More than 200 genomic regions have been identified and validated (association values (5x10-8) to be associated with CD, UC or IBD. These regions may contain multiple genes and the current challenge lies in identifying the causal gene in each of these. To address this problem, we performed a functional genomic screen of 145 genes from validated IBD loci, in a relevant intestinal epithelial cell model (HT-29). The results of this transcriptome-based screening revealed that the candidate IBD gene DUSP16 (a dual specificity phosphatase targeting MAP kinases (MAPKs) phosphorylation) as well as the known IBD gene KSR1 (a scaffold protein regulating the spatiotemporal activation of the ERK) regulate the expression of genes involved in intestinal differentiation and homeostasis. They induce, among others, the expression of the PIGR gene that encodes the polymeric immunoglobulin receptor. PIGR plays a role in transporting dimeric IgA molecules from the basolateral membrane of epithelial cells to the intestinal lumen, via transcytosis, where they play an essential role in protecting the epithelium against intestinal pathogens. Our hypothesis is that DUSP16 and KSR1 modulate the activity of MAPKs in intestinal epithelial cells to induce PIGR expression, thus participating in the maintenance of homeostasis of the intestinal barrier.

DUSP16 IS A NOVEL IBD GENE IMPLICATED IN THE REGULATION OF DIFFERENTIATION AND HOMEOSTASIS OF INTESTINAL EPITHELIAL CELLS

Abstract Inflammatory bowel disease (IBD) are chronic inflammatory diseases including Crohn’s disease (CD) and ulcerative colitis (UC). More than 200 genomic regions have been identified and validated (association values〈 5x10-8) to be associated with CD, UC or IBD. These regions may contain multiple genes and the current challenge lies in identifying the causal gene in each of these. To address this problem, we performed a functional genomic screen of 145 genes from validated IBD loci, in a relevant intestinal epithelial cell model (HT-29). The results of this transcriptome-based screening revealed that the candidate IBD gene DUSP16 (a dual specificity phosphatase targeting MAP kinases (MAPKs) phosphorylation) as well as the known IBD gene KSR1 (a scaffold protein regulating the spatiotemporal activation of the ERK) regulate the expression of genes involved in intestinal differentiation and homeostasis. They induce, among others, the expression of the PIGR gene that encodes the polymeric immunoglobulin receptor. PIGR plays a role in transporting dimeric IgA molecules from the basolateral membrane of epithelial cells to the intestinal lumen, via transcytosis, where they play an essential role in protecting the epithelium against intestinal pathogens. Our hypothesis is that DUSP16 and KSR1 modulate the activity of MAPKs in intestinal epithelial cells to induce PIGR expression, thus participating in the maintenance of homeostasis of the intestinal barrier. To better understand how DUSP16 modulates the expression of PIGR, we used an approach of over- expression (cDNA) and knockdown (shRNA) of DUSP16 in HT-29 cells. Our results confirmed that DUSP16 induction increases the expression of PIGR, whereas a knockdown of DUSP16 reduces the basal level of PIGR. Next we confirmed by Western Blot that the induction of DUSP16 was accompanied by a decrease in MAPK phosphorylation. The involvement of MAPKs was also confirmed through the use of chemical inhibitors specific for each MAPK, with inhibition of ERK and p38 showing the strongest induction of PIGR expression. We are currently analyzing known functional mutants of DUSP16 and KSR1 to determine their impact on MAPK activity and on PIGR expression. This work supports a role for PIGR in disease pathogenesis, adding to two recent studies that documented that patients suffering from UC accumulated somatic mutations in a group of genes regulating the expression of PIGR by Interleukin 17. The mutated genes, including PIGR, were positively selected in inflamed tissues, indicating the importance of the biological function occupied by this gene in the maintenance of homeostasis. In conclusion, our study successfully identified functional links between two genes from independent IBD loci, and suggests that these DUSP16 and KSR1 play a role in the process of epithelial transcytosis and the development of IBD.

Expression of polymeric immunoglobulin receptor (pIgR) and immunoglobulin (IgM) gene in mucosal-associated lymphoid tissues (MALT) of Labeo rohita fingerlings immunized with pDNA (pGPD-IFN) vaccine

Polymeric immunoglobulin receptor (pIgR) is a protein that transports Immunoglobulins (Igs) from epithelial cells into the external secretion system of the animal. In the present study, we characterized the partial pIgR gene from Labeo rohita and analyzed its expression in response to the pDNA (pGPD-IFN) vaccine, and studied its correlation with the expression of IgM, in the mucosal-associated lymphoid tissues (MALT). The significant (p < 0.05) up-regulation of pIgR mRNA was observed in the mucosal tissues of vaccinated fish by qRT-PCR. The highest expression of the gene was detected in gill tissue at 15 days post-vaccination (dpv) followed by skin and gut at 30 dpv. The expression of IgM also showed a similar pattern and indicated a direct correlation of pIgR expression in all the tested tissues. The protective immune response of the DNA vaccine was measured as the relative percentage of survival (RPS) by challenging vaccinated fish with live Edwardsiella tarda (1 × 105 CFU/Fish). The result showed a significantly high relative percentage survival (RPS) in the vaccinated group (47.05%) compared to the control group. Many factors contributing to the immune response of the vaccine. One of the most critical aspects is the rise in IgM level in local tissues. In other higher vertebrates, pIgR is reported to act as the transporter of IgM. The positive correlation in the expression of pIgR and IgM observed in the present study demonstrated the possible role of pIgR as the transporter of IgM in L. rohita. The study suggests the possibility of the secretory nature of IgM in fish.

Clinicopathological study on pIgR expression and tumor progression in advanced colorectal cancer

Clinicopathological study on pIgR expression and tumor progression in advanced colorectal cancer

Prolonged exposure to high humidity and high temperature environment can aggravate influenza virus infection through intestinal flora and Nod/RIP2/NF-κB signaling pathway

Seasonal influenza is an acute viral infection caused by influenza virus, which is often prevalent in the summer and winter. The influenza virus can infect pigs and poultry. Some literature reports that the influenza virus has an outbreak in summer. The summer climate is characterized by a high humidity and high temperature environment, which is the same as many animal feeding and growing environments. We established a flu animal model under a high temperature and humidity environment during the day to observe the impact of high humidity and high temperature environment on the mice after contracting the influenza virus. Our results indicate that the intestinal flora of 16 s rDNA cultured in High humidity and high temperature environment changes, the intestinal mucosal permeability increases, the expression of pIgR, sIgA, and IgA in the intestinal mucosal immune system decreases, and the NLR immune recognition signaling pathway NOD1 is activated. The expression of related genes such as NOD2, NF-κB, and pIgR increases, which leads to the increase of related inflammatory factors in the vicinity of the intestines, aggravating local inflammation. High humidity and high temperature environment can cause the expression of inflammatory cytokines in the body to rise, causing Th17/Treg immune imbalance, inhibiting Treg maturation and differentiation, and increasing the expression of IL-2, IL-6, and other cytokines, while the expression of IFN-γ and IL-17A decreases. This condition worsens after infection with the influenza virus. Overall, our study found that High humidity and high temperature environment affect the intestinal flora and the body's immune status, thereby aggravating the status of influenza virus infection.

Lung immunoglobulin A immunity dysregulation in cystic fibrosis.

BackgroundIn cystic fibrosis (CF), recurrent infections suggest impaired mucosal immunity but whether production of secretory immunoglobulin A (S-IgA) is impaired remains elusive. S-IgA is generated following polymeric immunoglobulin receptor (pIgR)-mediated transepithelial transport of dimeric (d-)IgA and represents a major defence through neutralisation of inhaled pathogens like Pseudomonas aeruginosa (Pa).MethodsHuman lung tissue (n = 74), human sputum (n = 118), primary human bronchial epithelial cells (HBEC) (cultured in air-liquid interface) (n = 19) and mouse lung tissue and bronchoalveolar lavage were studied for pIgR expression, IgA secretion and regulation.FindingsIncreased epithelial pIgR immunostaining was observed in CF lung explants, associated with more IgA-producing plasma cells, sputum and serum IgA, especially Pa-specific IgA. In contrast, pIgR and IgA transport were downregulated in F508del mice, CFTR-inhibited HBEC, and CF HBEC. Moreover, the unfolded protein response (UPR) due to F508del mutation, inhibited IgA transport in Calu-3 cells. Conversely, pIgR expression and IgA secretion were strongly upregulated following Pa lung infection in control and F508del mice, through an inflammatory host response involving interleukin-17.InterpretationA complex regulation of IgA secretion occurs in the CF lung, UPR induced by CFTR mutation/dysfunction inhibiting d-IgA transcytosis, and Pa infection unexpectedly unleashing this secretory defence mechanism.FundingThis work was supported by the Forton's grant of the King Baudouin's Foundation, Belgium, the Fondazione Ricerca Fibrosi Cistica, Italy, and the Fonds National de la Recherche Scientifique, Belgium.

Alterations in Intestinal Innate Mucosal Immunity of Weaned Pigs During Porcine Epidemic Diarrhea Virus Infection.

In the small intestine, localized innate mucosal immunity is critical for intestinal homeostasis. Porcine epidemic diarrhea virus (PEDV) infection induces villus injury and impairs digestive function. Moreover, the infection might comprise localized innate mucosal immunity. This study investigated specific enterocyte subtypes and innate immune components of weaned pigs during PEDV infection. Four-week-old pigs were orally inoculated with PEDV IN19338 strain (n = 40) or sham-inoculated (n = 24). At day post inoculation (DPI) 2, 4, and 6, lysozyme expression in Paneth cells, cellular density of villous and Peyer's patch microfold (M) cells, and the expression of polymeric immunoglobulin receptor (pIgR) were assessed in the jejunum and ileum by immunohistochemistry, and interleukin (IL)-1β and tumor necrosis factor (TNF)-α were measured in the jejunum by ELISA. PEDV infection led to a decrease in the ratios of villus height to crypt depth (VH-CD) in jejunum at DPI 2, 4, and 6 and in ileum at DPI 4. The number of villous M cells was reduced in jejunum at DPI 4 and 6 and in ileum at DPI 6, while the number of Peyer's patch M cells in ileum increased at DPI 2 and then decreased at DPI 6. PEDV-infected pigs also had reduced lysozyme expression in ileal Paneth cells at DPI 2 and increased ileal pIgR expression at DPI 4. There were no significant changes in IL-1β and TNF-α expression in PEDV-infected pigs compared to controls. In conclusion, PEDV infection affected innate mucosal immunity of weaned pigs through alterations in Paneth cells, villous and Peyer's patch M cells, and pIgR expression.

High expression levels of polymeric immunoglobulin receptor are correlated with chemoresistance and poor prognosis in pancreatic cancer.

Pancreatic cancer has extremely poor prognosis, warranting the discovery of novel therapeutic and prognostic markers. The expression of polymeric immunoglobulin receptor (pIgR), a key component of the mucosal immune system, is increased in several cancers. However, its clinical relevance in pancreatic cancer remains unclear. In the present study, the prognostic value of pIgR in pancreatic cancer patients after surgical resection was assessed and it was determined that the expression of pIgR was correlated with poor prognosis. Ten pancreatic cancer patient-derived xenograft (PDX) lines were established, followed by next-generation sequencing of tumor tissues from these lines after standard chemotherapy. Immunohistochemical analysis of chemoresistance-related molecules using 77 pancreatic cancer tissues was also performed. The expression of pIgR mRNA in the PDX group treated with anticancer drugs was higher than in the untreated group. High pIgR expression in tissue specimens from 77 pancreatic cancer patients was significantly associated with poor prognosis and was revealed to be an independent prognostic factor, predicting poor outcomes. High pIgR mRNA and protein levels were independent prognostic factors, indicating that pIgR could be a novel predictor for poor prognosis of pancreatic cancer patients.

Differential Activity of Key Super-Enhancers Drives Disease-Defining Oncogenes in B Cell Cancers

Abstract Normal B cell development depends upon exquisitely timed and calibrated epigenetic and transcriptional changes. Significant perturbations should result in cell death, but rarely, cells escape this quality control system. We compared 3 types of B cell cancer and normal lymphocytes to identify common and distinct epigenetic perturbations that promote oncogenesis. Purified CD19+ B cells from 49 patients (18 Follicular, 12 Diffuse Large B Cell, 19 Chronic Lymphocytic Lymphomas) and 20 donor tonsils were subjected to chromatin immunoprecipitation (ChIP-) and sequencing for H3K4me1, H3K9/14ac, and H3K27ac; FAIRE-seq for open chromatin; RNA-seq for gene expression; and SNP arrays for genome mapping. These integrative studies identified 7,772 differentially bound regulatory regions (DBRs) between lymphoma subtypes and tonsillar B cells. Expression of nearby genes corresponded with ChIP/FAIRE-seq changes at these elements, particularly near DBRs in 1,367 identified super-enhancers. Several of the latter regulate known lymphoma oncogenes, including BCL6, BCL2, and IRF4. We also identified a novel super-enhancer connected to the aberrant expression of FCMR and PIGR. We confirmed enhancer activity using luciferase reporter assays and altered protein expression using immunofluorescence. FCMR regulates the surface expression of BCR; B cells deficient in FCMR have increased tonic BCR signaling and increased differentiation. We suggest that its overexpression may contribute to the chronic active BCR signaling that drives many B cell cancers. In sum, our studies defined distinct enhancer profiles among B cell cancer subtypes and identified a novel regulatory mechanism that may contribute to aberrant BCR signaling in lymphoma.

IL–17 receptor signaling regulates Citrobacter rodentium growth

Abstract The type 17 cytokine receptors are thought to play critical roles in mucosal immunity. We have shown that intestinal epithelial expression of IL–17 receptor control the development of microbiota in the terminal ileum and conditional deletion of these receptors results in overgrowth of segmented filamentous bacteria. To study the roles of these receptors in response to an attaching and effacing pathogen we challenged intestinal specific Il17ra mice and Il17rc mice with Citrobacter rodentium (C. rodentium). Conditional deletion of Il17ra and l17rc Iresulted in increased bacterial growth in the colon as well as enhanced dissemination to the liver suggesting that intestinal epithelial IL–17 receptors expression is required for control of this infection. This was supported by unbiased RNAseq analysis of the colon that showed diminished expression of Pigr, Tnfsf13 and Nox1 in the absence of Il17ra. IgA has crucial role in mucosal immunity to protect from pathogenic bacteria. PIGR binds dimeric IgA and translocation into lumen, while TNFSF13 activates induce differentiation to plasma cells following–crass switch. C. rodentium specific IgA in stool and C. rodentium specific IgA producing cells in lamina propria were reduced in Il17ra mice. These results suggested IL-17 receptor signaling regulates transcytosis of C. rodentium specific IgA as well as secretion of bacteria specific IgA. On the other hands Nox1 can produce apical hydrogen peroxide. Nox1 null mice were more sensitive for C. rodentium infection. Furthermore Nox1 was expressed by IL–17A stimulation in colonic organoid. Taken together, IL–17 receptor signaling control to produce C. rodentium specific IgA through PIGR and TNFSF13 as well as hydrogen peroxide through NOX1.

Salivary Immunoglobulin A Secretion and Polymeric Ig Receptor Expression in the Submandibular Glands Are Enhanced in Heat-Acclimated Rats.

Salivary immunoglobulin A (IgA) plays a critical role in mucosal immunity. Chronic exposure to moderate heat induces heat acclimation, which modifies salivary functions. However, the changes in salivary IgA secretion in heat-acclimated rats are unclear. In this study, we investigated salivary IgA secretion and the expression of polymeric Ig receptor (pIgR), a key mediator of mucosal IgA secretion, in the submandibular glands (SMGs) of heat-acclimated rats. Following maintenance at an ambient temperature (Ta) of 24 ± 0.1 °C for 10 days, male Wistar rats were subjected to Ta of 32 ± 0.2 °C for 5 days (HE group) for heat acclimation or maintained at Ta of 24 ± 0.1°C (CN group). The rats were then anesthetized, pilocarpine (0.5 mg/kg) was intraperitoneally injected, and saliva was collected. Afterward, the SMGs and plasma were sampled. The salivary IgA concentration and IgA flow rate were significantly higher in the HE group than in the CN group. Similarly, SMG pIgR expression was significantly higher in HE rats. The levels of plasma cytokines, including interleukin (IL)-5, IL-6, and interferon-γ, were significantly greater in HE rats than in CN rats. Heat acclimation may enhance oral immunity through salivary IgA secretion and pIgR upregulation in the SMGs.

Isolation and Identification of Porcine Deltacoronavirus and Alteration of Immunoglobulin Transport Receptors in the Intestinal Mucosa of PDCoV-Infected Piglets.

Porcine deltacoronavirus (PDCoV) is a porcine enteropathogenic coronavirus that causes watery diarrhea, vomiting, and frequently death in piglets, causing serious economic losses to the pig industry. The strain CHN-JS-2017 was isolated and identified by cytopathology, immunofluorescence assays, transmission electron microscopy, and sequence analysis. A nucleotide sequence alignment showed that the whole genome of CHN-JS-2017 is 97.4%–99.6% identical to other PDCoV strains. The pathogenicity of the CHN-JS-2017 strain was investigated in orally inoculated five-day-old piglets; the piglets developed acute, watery diarrhea, but all recovered and survived. CHN-JS-2017 infection-induced microscopic lesions were observed, and viral antigens were detected mainly by immunohistochemical staining in the small intestine. The neonatal Fc receptor (FcRn) and polymeric immunoglobulin receptor (pIgR) are crucial immunoglobulin (Ig) receptors for the transcytosis ofimmunoglobulin G (IgG), IgA, or IgM. Importantly, CHN-JS-2017 infected five-day-old piglets could significantly down-regulate the expression of FcRn, pIgR, and nuclear factor-kappa B (NF-κB)in the intestinal mucosa. Note that the level of FcRn mRNA in the intestinal mucosa of normal piglets is positively correlated with pIgR and NF-κB. At the same time, the expressions of FcRn, pIgR, and NF-κB mRNA are also positively correlated in infected piglets. These results may help explain the immunological and pathological changes associated with porcine deltacorononirus infection.

Gait adaptations in children with unilateral cerebral palsy and typically developing children when walking on uneven ground

The receptor responsible for maternofetal transmission of immunoglobulin (Igs) in the teleosts is not clear. Polymeric immunoglobulin receptor (pIgR) specifically binds with IgA and IgM and mediates the transcytosis of intracellular polymeric immunoglobulins (pIgs) at the mucosal surface to protect against pathogens. Hence there is a possibility that it may be involved in the transmission of maternal Igs. The aim of the present study was to detect the expression and localization of pIgR during embryonal development in turbot (Scophthalmus maximus). pIgR gene was first cloned from eggs and embryos of turbot with or without parent immunization. The expression and distribution of pIgR in unfertilized egg and in embryos ranging from day 1 to day 5 after fertilization were analyzed using reverse transcriptase quantitative polymerase chain reaction and in situ hybridization. pIgR gene was detected in all eggs and embryos at different stages of development, with the highest level detected on the 5th day. pIgR mRNA was observed to be first located in the whole blastoderm and enveloped the yolk sac. Later, it was located around entoderm including primary digestive tract and pronephric tubule tract, and finally it was located at the joint of abdomen and vitelline membrane. Then, Eukaryotic expression plasmid carrying pIgR gene was constructed and transfected into HEK293T cells. Results showed mature pIgR protein located on the cellular membrane, and could bound IgM in vitro. Our findings provide information for studying the involvement of pIgR in maternal Igs transportation in turbot.