Goblet Cells In Small Intestine Research Articles

NAD+ precursors and bile acid sequestration treat preclinical refractory environmental enteric dysfunction.

Environmental enteric dysfunction (EED) is a diffuse small bowel disorder associated with poor growth, inadequate responses to oral vaccines, and nutrient malabsorption in millions of children worldwide. We identify loss of the small intestinal Paneth and goblet cells that are critical for innate immunity, reduced villous height, increased bile acids, and dysregulated nicotinamide adenine dinucleotide (NAD+) synthesis signaling as potential mechanisms underlying EED and which also correlated with diminished length-for-age z score. Isocaloric low-protein diet (LPD) consumption in mice recapitulated EED histopathology and transcriptomic changes in a microbiota-independent manner, as well as increases in serum and fecal bile acids. Children with refractory EED harbor single-nucleotide polymorphisms in key enzymes involved in NAD+ synthesis. In mice, deletion of Nampt, the gene encoding the rate-limiting enzyme in the NAD+ salvage pathway, from intestinal epithelium also reduced Paneth cell function, a deficiency that was further aggravated by LPD. Separate supplementation with NAD+ precursors or bile acid sequestrant partially restored LPD-associated Paneth cell defects and, when combined, fully restored all histopathology defects in LPD-fed mice. Therapeutic regimens that increase protein and NAD+ contents while reducing excessive bile acids may benefit children with refractory EED.

Antenatal Ureaplasma infection induces ovine small intestinal goblet cell defects: a strong link with NEC pathology

ABSTRACT Disruption of the intestinal mucus barrier and intestinal epithelial endoplasmic reticulum (ER) stress contribute to necrotizing enterocolitis (NEC). Previously, we observed intestinal goblet cell loss and increased intestinal epithelial ER stress following chorioamnionitis. Here, we investigated how chorioamnionitis affects goblet cells by assessing their cellular characteristics. Importantly, goblet cell features are compared with those in clinical NEC biopsies. Mucus thickness was assessed as read-out of goblet cell function. Fetal lambs were intra-amniotically (IA) infected for 7d at 122 gestational age with Ureaplasma parvum serovar-3, the main microorganism clinically associated with chorioamnionitis. After preterm delivery, mucus thickness, goblet cell numbers, gut inflammation, epithelial proliferation and apoptosis and intestinal epithelial ER stress were investigated in the terminal ileum. Next, goblet cell morphological alterations (TEM) were studied and compared to human NEC samples. Ileal mucus thickness and goblet cell numbers were elevated following IA UP exposure. Increased pro-apoptotic ER stress, detected by elevated CHOP-positive cell counts and disrupted organelle morphology of secretory cells in the intestinal epithelium, was observed in IA UP exposed animals. Importantly, comparable cellular morphological alterations were observed in the ileum from NEC patients. In conclusion, UP-driven chorioamnionitis leads to a thickened ileal mucus layer and mucus hypersecretion from goblet cells. Since this was associated with pro-apoptotic ER stress and organelle disruption, mucus barrier alterations seem to occur at the expense of goblet cell resilience and may therefore predispose to detrimental intestinal outcomes. The remarkable overlap of these in utero findings with observations in NEC patients underscores their clinical relevance.

Indoleamine 2,3-dioxygenase 1 regulates cell permissivity to astrovirus infection

Astroviruses cause a spectrum of diseases spanning asymptomatic infections to severe diarrhea, but little is understood about their pathogenesis. We previously determined that small intestinal goblet cells were the main cell type infected by murine astrovirus-1. Here, we focused on the host immune response to infection and inadvertently discovered a role for indoleamine 2,3-dioxygenase 1 (Ido1), a host tryptophan catabolizing enzyme, in the cellular tropism of murine and human astroviruses. We identified that Ido1 expression was highly enriched among infected goblet cells, and spatially corresponded to the zonation of infection. Because Ido1 can act as a negative regulator of inflammation, we hypothesized it could dampen host antiviral responses. Despite robust interferon signaling in goblet cells, as well as tuft cell and enterocyte bystanders, we observed delayed cytokine induction and suppressed levels of fecal lipocalin-2. Although we found Ido-/- animals were more resistant to infection, this was not associated with fewer goblet cells nor could it be rescued by knocking out interferon responses, suggesting that IDO1 instead regulates cell permissivity. We characterized IDO1-/- Caco-2 cells and observed significantly reduced human astrovirus-1 infection. Together this study highlights a role for Ido1 in astrovirus infection and epithelial cell maturation.

MHCII Expression by Intestinal Goblet Cells in Immune Homeostasis

Abstract As the primary barrier in the gut, intestinal epithelial cells (IECs) are positioned to promote tolerance and immunity against pathogens. MHCII is highly expressed on IECs, however MHCII expression on epithelial cell subsets is largely unexplored. Goblet cells (GCs) are specialized epithelial cells that have critical role in barrier maintenance and immunity. GC can form Goblet cells associated passage (GAPs) and deliver luminal antigens to lamina propria (LP) antigen presenting cells (APC) to induce adaptive immune responses. Here, we report that MHCII is highly expressed on small intestinal GCs as compared with other IECs and colon IECs, which do not form GAPs in the steady state. Moreover, expression of coinhibitory and costimulatory molecules by GCs was higher when compared with other IECs. Interestingly, flow analysis and quantification of MHCII on CD45.2 +MHC-II −/−donor-derived leukocytes showed MHCII acquisition by donor-derived small intestinal lamina propria (siLP) APCs 7 weeks after BM-transplant into CD45.1 +recipients. Indeed, carbachol, which induces GAPs formation resulted in increased MHCII acquisition by CD45.2 +MHC-II −/−donor-derived siLP MNPs. Furthermore, selective deletion of MHCII on GCs, resulted in a significant reduction of transferred dietary antigen specific OT-II +CD45.1 +CD4 +T cells in mLN in a model of oral tolerance. Bulk RNAseq analysis on the small intestine of mice with GC deletion of MHCII revealed an expansion of B cell responses and significant increase in IgA+ cells in Peyer’s patches. This data suggests that GC expression of MHCII has a role in antigen-specific responses to luminal antigens and in regulating intestinal homeostasis. Supported by grants from NIH

The protective effect of Ganoderma atrum polysaccharide on intestinal barrier function damage induced by acrylamide in mice through TLR4/MyD88/NF-κB based on the iTRAQ analysis.

The potential mechanism for the protective effect of Ganoderma atrum (G. atrum) polysaccharide (PSG-1) on acrylamide (AA) induced intestinal damage in mice was explored. Results showed that PSG-1 pretreatment prevented AA-induced injury by decreasing intestinal permeability and serum D-lactate acid (D-Lac) levels and increasing the number of small intestinal goblet cells and IgA secreting cells. In addition, PSG-1 pretreatment effectively reduced malondialdehyde (MDA) level and raised superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) activities in the intestine. Furthermore, PSG-1 administration decreased the levels of pro-inflammatory factors including IL-1β, TNF-α, and IL-6, while the anti-inflammatory factor IL-10 was elevated. Meanwhile, PSG-1 could increase the performance of tight junction (TJ) proteins such as Occludin, Claudin-1 and ZO-1. Moreover, according to the isobaric tag for relative and absolute quantitation (iTRAQ) and Western blot results, PSG-1 could reduce AA-induced intestinal injury through TLR4/MyD88/NF-κB signaling pathway. Overall, the present study suggested that PSG-1 protected intestinal permeability and barrier function in mice via reducing inflammation and oxidative stress, and effectively prevented AA-induced intestinal injury in mice.

Bacillus subtilis programs the differentiation of intestinal secretory lineages to inhibit Salmonella infection.

The role of intestinal microbiota on fate determination of intestinal epithelial cells has not been extensively examined. In this study, we explore the effect of Bacillus subtilis on programmed intestinal epithelial differentiation. We find that B.subtilis stimulates the differentiation of intestinal secretory cells. Moreover, B.subtilis inhibits the Notch pathway to reduce the expression of hairy and enhancer of split 1, thereby shifting intestinal stem cell differentiation toward a secretory cell fate. Moreover, we demonstrate that the programming effect of B.subtilis on intestinal differentiation is Toll-like receptor 2 pathway dependent. B.subtilis is associated with increased numbers of Paneth and goblet cells in the intestine. This results in the production of antimicrobial peptides to protect the intestinal mucosal barrier against Salmonella typhimurium. This study demonstrates that B.subtilis contributes to the differentiation of secretory cells by affecting Notch pathway signaling to maintain the intestinal barrier.

Enterotoxigenic Escherichia coli Degrades the Host MUC2 Mucin Barrier To Facilitate Critical Pathogen-Enterocyte Interactions in Human Small Intestine.

Enterotoxigenic Escherichia coli (ETEC) isolates are genetically diverse pathological variants of E. coli defined by the production of heat-labile (LT) and/or heat-stable (ST) toxins. ETEC strains are estimated to cause hundreds of millions of cases of diarrheal illness annually. However, it is not clear that all strains are equally equipped to cause disease, and asymptomatic colonization with ETEC is common in low- to middle-income regions lacking basic sanitation and clean water where ETEC are ubiquitous. Recent molecular epidemiology studies have revealed a significant association between strains that produce EatA, a secreted autotransporter protein, and the development of symptomatic infection. Here, we demonstrate that LT stimulates production of MUC2 mucin by goblet cells in human small intestine, enhancing the protective barrier between pathogens and enterocytes. In contrast, using explants of human small intestine as well as small intestinal enteroids, we show that EatA counters this host defense by engaging and degrading the MUC2 mucin barrier to promote bacterial access to target enterocytes and ultimately toxin delivery, suggesting that EatA plays a crucial role in the molecular pathogenesis of ETEC. These findings may inform novel approaches to prevention of acute diarrheal illness as well as the sequelae associated with ETEC and other pathogens that rely on EatA and similar proteases for efficient interaction with their human hosts.

PGD2 and CRTH2 counteract Type 2 cytokine-elicited intestinal epithelial responses during helminth infection.

Type 2 inflammation is associated with epithelial cell responses, including goblet cell hyperplasia, that promote worm expulsion during intestinal helminth infection. How these epithelial responses are regulated remains incompletely understood. Here, we show that mice deficient in the prostaglandin D2 (PGD2) receptor CRTH2 and mice with CRTH2 deficiency only in nonhematopoietic cells exhibited enhanced worm clearance and intestinal goblet cell hyperplasia following infection with the helminth Nippostrongylus brasiliensis. Small intestinal stem, goblet, and tuft cells expressed CRTH2. CRTH2-deficient small intestinal organoids showed enhanced budding and terminal differentiation to the goblet cell lineage. During helminth infection or in organoids, PGD2 and CRTH2 down-regulated intestinal epithelial Il13ra1 expression and reversed Type 2 cytokine-mediated suppression of epithelial cell proliferation and promotion of goblet cell accumulation. These data show that the PGD2-CRTH2 pathway negatively regulates the Type 2 cytokine-driven epithelial program, revealing a mechanism that can temper the highly inflammatory effects of the anti-helminth response.

Age-related histochemical investigations of small intestinal goblet cells in bronze turkeys (Meleagris gallopavo gallopavo)

The aim of the study was to investigate the goblet cell types and their density in the small intestine of bronze turkey (Meleagris meleagris gallopovo), by means of Alcian blue-PAS staining. Sixty birds from 10 age groups were used. In the duodenum and jejunum, goblet cells produced acid, neutral and mixed mucins, while in the jejunum - acid mucins. A negative relationship was observed between cell density and either duodenum or jejunum lengths; such a correlation was not established in the ileum.

Delayed access to feed affects broiler small intestinal morphology and goblet cell ontogeny

Broilers are often deprived of feed and water for up to 48 h after hatch. This delayed access to feed (DAF) can inhibit small intestine development. The objective of this study was to determine the effects of DAF on small intestinal morphology, mRNA abundance of the goblet cell marker Muc2 and absorptive cell marker PepT1, and the distribution of goblet cells in young broilers. Cobb 500 chicks, hatching within a 12-h window, were randomly allocated into 3 groups: control with no feed delay (ND), 24-h feed delay (DAF24), and 36-h feed delay (DAF36). Morphology, gene expression, and in situ hybridization analyses were conducted on the duodenum, jejunum, and ileum at 0, 24, 36, 72, 120, and 168 h after hatch. Statistical analysis was performed using a t test for ND and DAF24 at 24 h. A 2-way ANOVA and Tukey's HSD test (P < 0.05) were used for ND, DAF24, and DAF36 from 36 h. At 24 to 36 h, DAF decreased the ratio of villus height/crypt depth (VH/CD) in the duodenum but increased VH/CD in the ileum due to changes in CD, whereas at 72 h, DAF decreased VH/CD due to a decrease in VH. The mRNA abundance of PepT1 was upregulated, while Muc2 mRNA was downregulated in DAF chicks. Cells expressing Muc2 mRNA were present along the villi and in the crypts. The ratio of the number of goblet cells found in the upper half to the lower half of the villus was greater in DAF chicks than in ND chicks, suggesting that DAF affected the appearance of new goblet cells. The number of Muc2 mRNA-expressing cells in the crypt, however, was generally not affected by DAF. In conclusion, DAF transiently affected small intestinal morphology, upregulated PepT1 mRNA, downregulated Muc2 mRNA, and changed the distribution of goblet cells in the villi. By 168 h, however, these parameters were not different between ND, DAF24, and DAF36 chicks.

Astrovirus infects actively secreting goblet cells and alters the gut mucus barrier

Astroviruses are a global cause of pediatric diarrhea, but they are largely understudied, and it is unclear how and where they replicate in the gut. Using an in vivo model, here we report that murine astrovirus preferentially infects actively secreting small intestinal goblet cells, specialized epithelial cells that maintain the mucus barrier. Consequently, virus infection alters mucus production, leading to an increase in mucus-associated bacteria and resistance to enteropathogenic E. coli colonization. These studies establish the main target cell type and region of the gut for productive murine astrovirus infection. They further define a mechanism by which an enteric virus can regulate the mucus barrier, induce functional changes to commensal microbial communities, and alter host susceptibility to pathogenic bacteria.

Topographic Lectin Mapping of the Epithelial Cell Surface in Normal Intestine and Celiac Disease

The etiology and pathogenesis of celiac disease remains obscure but remains the focus of intense research investigation. It is generally believed to be an immune-mediated small intestinal mucosal disorder that can cause diarrhea, impaired nutrient assimilation and weight loss. A key component in this process occurs at the intestinal epithelial cell surface that is closely associated with the luminal intestinal microbiome. Here, epithelial membrane glycoproteins and glycolipids are present along with adsorbed molecules that permit interaction with the intestinal microbiome. In recent years, use of specific sugar residue seeking proteins, lectins, that can be found in the diet have been employed topographically to map the small intestinal cell surface and goblet cell secretory mucins to further elucidate the structure and function of this tissue. Evidence has accumulated to indicate that this microenvironment may be critically important in further understanding the etiology and pathogenesis of celiac disease and other sprue-like intestinal disorders.

Sanguinarine has anthelmintic activity against the enteral and parenteral phases of trichinella infection in experimentally infected mice

Trichinellosis is a zoonotic parasitic disease caused by Trichinella spiralis, and it is also a widely prevalent foodborne parasitic disease. At present, albendazole and benzimidazole are the most commonly used therapeutic drugs for the clinical treatment of trichinellosis, but they have many side effects. Sanguinarine is a benzophenanthridine alkaloid that has biological activity, such as antibacterial, antitumour and antiparasitic activities. Therefore, the present study aimed to evaluate the anti-Trichinella effect of sanguinarine in vivo and in vitro. The results showed that sanguinarine had a lethal effect on muscle larvae, adults and new-borne larvae in vitro. The damage to adults treated with sanguinarine was observed by scanning electron microscopy. Sanguinarine could significantly reduce the burden of worms in mice during the pre-adult, migrating larva and encysted larva stages. The ratio of intestinal villus to crypt (V/C) in mice treated with sanguinarine was significantly higher than that in non-treated control mice. Compared with the non-treated control group, the sanguinarine-treated group exhibited a significantly increased number of small intestine goblet cells. The level of reactive oxygen species (ROS) in the serum of mice treated with sanguinarine was significantly higher than that of the control group mice in the pre-adult and encysted larva stages. This study suggests that sanguinarine is a potential drug against trichinellosis.

Synthesis of CSK-DEX-PLGA Nanoparticles for the Oral Delivery of Exenatide to Improve Its Mucus Penetration and Intestinal Absorption.

The oral absorption of exenatide, a drug for type 2 diabetes treatment, can be improved by using nanoparticles (NPs) for its delivery. To improve the mucus penetration and intestinal absorption of exenatide, we designed a block copolymer, CSKSSDYQC-dextran-poly(lactic-co-glycolic acid) (CSK-DEX-PLGA), and used it for the preparation of exenatide-loaded NPs. The functionalized exenatide-loaded NPs composed of CSK-DEX-PLGA were able to target intestinal epithelial cells and reduce the mucus-blocking effect of the intestine. Moreover, the CSK modification of DEX-PLGA was found to significantly promote the absorption efficiency of NPs in the small intestine based on in vitro ligation of the intestinal rings and an examination of different intestinal absorption sites. Compared to DEX-PLGA-NPs (DPs), the absorption of CSK-DEX-PLGA-NPs (CDPs) was increased in the villi, allowing the drug to act on gobletlike Caco-2 cells through clathrin-, caveolin-, and gap-mediated endocytosis. Furthermore, the enhanced transport ability of CDPs was observed in a study on Caco-2/HT-29-MTX cocultured cells. CDPs exhibited a prolonged hypoglycemic response with a relative bioavailability of 9.2% in diabetic rats after oral administration. In conclusion, CDPs can target small intestinal goblet cells and have a beneficial effect on the oral administration of macromolecular peptides as a nanometer-sized carrier.

Beneficial effects of Saccharomyces cerevisiae RC016 in weaned piglets: in vivo and ex vivo analysis.

Probiotics represents an alternative to replace antibiotics as growth promoters in animal feed and are able to control enteric bacterial diseases and to improve gut immunity. Saccharomyces cerevisiae RC016 showed previously inhibition/coagregation of pathogens) and mycotoxins adsorbent ability (aflatoxin B1, ochratoxin A and zearalenone). The aim of this work was to evaluate beneficial properties of S. cerevisiae RC016 in a non-inflammatory in vivo model in weaned piglets and in an intestinal inflammation ex vivo model induced by the mycotoxin deoxynivalenol (DON). Secretory immunoglobulin A (s-IgA) levels, intestinal cytokines, goblet cells and production parameters were evaluated in a pig model. For the in vivo assays, twelve pigs were weaned at 21 days and assigned to two groups: Control (n=6) and Yeast (n=6). Animals received yeast strain for three weeks. After 22 days the small intestine was recovered for determination of goblet cells and s-IgA. For the ex vivo assay, jejunal explants were obtained from 5 weeks old crossbred piglets and treated as follow: (1) control; (2) treated for 3 h with 10 μM DON used as an inflammatory stressor; (3) incubated with 107 cfu/ml yeast strain; (4) pre-incubated 1 h with 107 cfu/ml yeast strain and then treated for 3 h with 10 μM DON. CCL20, interleukin (IL)-1β, IL-8 and IL-22 gene expression was determined by qPCR. Oral administration of S. cerevisiae RC016 increased s-IgA, the number of goblet cells in small intestine and all the growth parameters measured. In the ex vivo model, the cytokine profile studied showed a potential anti-inflammatory effect of the administration of the yeast. In conclusion, S. cerevisiae RC016 is a promising candidate for feed additives formulation to improve animal growth and gut immune system. This yeast strain could be able to improve the gut health through counteracting the weaning-associated intestinal inflammation in piglets.

Abstract P235: Altered Brain-Gut-Lung Axis in Hypoxia-Induced Pulmonary Hypertension

Background: Recent evidence indicate that gut microbiota plays important role in pathogenesis and progression of chronic lung diseases such as asthma, respiratory infections and COPD. However, implications of this gut-lung communication and involvement of peripheral and neural immune system in pulmonary hypertension (PH) remains unknown. Objective: Investigate the hypothesis that increased activation of microglial cells, autonomic nervous system, altered gut pathology and gut microbiota are associated with PH suggesting a dysfunctional brain-gut-lung axis in PH pathology. Methods: C57BL/6 (WT) male mice were exposed to chronic hypoxia (10%O2) or Normoxia for 4 weeks in a ventilated chamber (n=5-8/group). Millar pressure catheter was used to measure pulmonary hemodynamics, Iba1 specific antibody for immunohistochemical analysis of microglial cells and fecal 16S rDNA for gut microbiota analysis. Results: Hypoxia induced a 77% increase in right ventricular (RV) systolic pressure (RVSP: N:19.5 ± 2 mmHg Vs H:33.7 ± 2, p&lt;0.001) and RV hypertrophy (RVH: N: 0.139 ± 0.09 Vs H: 0.192± 0.008). This was associated with substantial enhancement in sympathetic activity (LF/HF: N:0.23 ± 0.8 mmHg Vs H: 1.19 ± 0.08, p&lt;0.001) and increase in number of microglial cells in autonomic brain regions, predominantly the paraventricular nucleus of hypothalamus. Characteristics of gut pathology such as ~50% increase in fibrotic area and muscularis layer thickness and significantly decreased villi length and number of goblet cells in small intestine were also observed. Also, principal coordinate analysis of the bacterial composition profile showed a clear separation and clustering of bacterial genera of hypoxic and normoxic mice (ANOSIM p&lt;0.001). Conclusions: (I) Hypoxia-induced pulmonary and cardiac pathophysiology is associated with increased microglia in cardiorespiratory-relevant areas and enhanced sympathetic activity. (II) Fibrotic area and muscularis layer thickness increased while villi length and number of goblet cells decreased in gut (III) gut microbiota are altered. Together, these observations indicated an altered brain-gut-lung axis in PH.

Influence of β-galacto-oligosaccharide on growth performance and components of intestinal barrier in broilers during heat stress

This study aimed to investigate the influence of β-galacto-oligosaccharides (β-GOS) on growth performance, organ development and intestinal microarchitecture of broilers during heat stress. Day-old chicks (n = 125) were divided into five groups. The control or thermoneutral zone group (TNZ) was raised under standard management until the 35th day. Four groups were exposed to cyclic heat stress (35 °C 8 h/d) from the 22nd to the 35th day. The TNZ and heat stress control (HSCT) groups were fed a corn-based diet and HS + 0.1% β-GOS; HS + 0.2% β-GOS; and HS + 0.5% β-GOS were fed a corn-based diet supplemented with β-GOS (0.1%, 0.2%, and 0.5%), respectively. Exposure to heat stress reduced feed consumption, feed efficiency and the relative weight of the liver, bursa of Fabricius, and small intestine, compared with the TNZ group. Morphometric evaluation of the small intestine revealed reduced villus surface area, villus height to crypt depth ratio (VH : CD) and intraepithelial lymphocytes (IELs) in all segments, and reduced acidic goblet cells (AGCs) in the ileum of the HSCT group compared with the TNZ group. Compared with the HSCT group, dietary β-GOS (0.2% and 0.5%) improved the feed efficiency and relative weight of the small intestine. Furthermore, dietary β-GOS (0.1%) increased villus surface area in the duodenum and IEL count in the small intestine compared with the HSCT group. Dietary β-GOS 0.5% increased villi surface area (VSA) in the jejunum and ileum, whereas the IEL count in the small intestine and acidic goblet cells (AGCs) in the jejunum and ileum were reduced compared with the HSCT group. In conclusion, dietary supplementation of β-GOS (0.2% and 0.5%) improved the growth performance and intestinal microarchitecture of broilers during heat exposure, along with partial immune stimulation. Keywords : Feed efficiency, goblet cell, intraepithelial lymphocytes, mucosal architecture, prebiotics, poultry, villus morphometry

The prostaglandin D2 receptor CRTH2 suppresses epithelial cell responses during intestinal helminth infection

Abstract Type 2 inflammation is required for expulsion of intestinal helminth parasites and is characterized by immune cell activation, type 2 cytokine production, and increased mucin production by epithelial goblet cells. Previous studies show that the prostaglandin D2 (PGD2) receptor chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) promotes type 2 inflammation in the lung via effects on immune cells, but how CRTH2 influences helminth-induced type 2 inflammation in the intestine was unclear. Here we show that CRTH2-deficient mice cleared infection with the mouse-adapted helminth parasite Nippostrongylus brasiliensis more efficiently and had increased numbers of mucin-producing goblet cells in the small intestine post-infection compared to wild type mice, despite similar levels of worm establishment. These data suggest that CRTH2 restrains goblet cell responses during intestinal helminth infection, in contrast to its pro-inflammatory role in the lung. Consistent with this idea, bone marrow-chimeric mice in which only non-hematopoietic cells lacked CRTH2 also cleared parasites more efficiently than chimeric wild type mice and had increased numbers of small intestinal goblet cells. In addition, murine small intestinal organoids that were stimulated with type 2 cytokines downregulated expression of goblet cell-associated genes following culture with PGD2. Taken together, these data suggest that the PGD2-CRTH2 pathway suppresses epithelial goblet cell responses following helminth-induced type 2 inflammation in the intestine. These findings may inform the development and use of drugs that inhibit this pathway during intestinal type 2 inflammatory disease, such as food allergy.

Small intestinal Goblet cells and Goblet cell associated antigen passages assist translocation of pathogenic bacteria

Abstract The intestinal epithelium forms an essential physicochemical barrier that separates luminal bacteria from underlying immune cells of the intestinal mucosa. Appropriate exposure of the immune cells to luminal antigens is crucial to ensure intestinal homeostasis and to respond to enteric infections. We recently demonstrated a previously unappreciated role of small intestinal (SI) Goblet cells (GCs) in delivering luminal antigens across the epithelium by forming goblet-cell associated antigen passages (GAPs) in the steady state. How pathogenic bacteria affect the formation of SI GAPs and the ability of pathogens to use GAPs as a portal of entry is largely unexplored. Here we report that in conventionally housed mice, luminal exposure to invasive Salmonella typhimurium, but not mutant non-invasive S. typhimurium, results in inhibition of SI GAPs within minutes. Moreover, overriding the ability of GCs to sense the pathogen by deleting MyD88 in GCs or inhibiting EGFR activation downstream of MyD88 during S. typhimurium infection allowed GAP formation, suggesting that GC intrinsic sensing of an invasive pathogen to shut off GAPs is a host defense mechanism. Fluorescent wildtype S. typhimurium preferentially localized around and within GCs forming GAPs. Deletion of GCs prevented the translocation of wildtype S. typhimurium to the SI draining mesenteric lymph node following oral infection, indicating that S. typhimurium uses GCs as a portal of entry. These findings identify a role of GC sensing of an invasive pathogen in inhibiting antigen delivery to the immune system and in limiting the translocation of pathogenic bacteria.

Induction of Sda-sialomucin and sulfated H-sulfomucin in mouse small intestinal mucosa by infection with parasitic helminth

Mucin is a major component of mucus on gastrointestinal mucosa. Mucin alteration in the host is considered to be the principal event for expulsion of intestinal helminths. However, it is unclear what mucin alterations are induced by various helminth infections. In this study, the alterations of mouse small intestinal mucin after infection with two nematodes, Nippostrongylus brasiliensis and Heligmosomoides polygyrus, which parasitize the jejunal epithelium, and a cestode, Vampirolepis nana, which parasitizes the ileal epithelium, were examined biochemically and histologically using two anti-mucin monoclonal antibodies (mAbs), HCM31 and PGM34, which recognize Sda antigen, NeuAcα2–3(GalNAcβ1–4)Galβ1-4GlcNAcβ-, and sulphated H type 2 antigen, Fucα1-2Galβ1-4GlcNAc(6SO3H)β-, respectively. The goblet cell mucins that reacted with HCM31 increased conspicuously on the jejunal mucosa concurrently with expulsion of N. brasiliensis. Increased levels of HCM31-reactive mucins were observed in the jejunal mucosa after H. polygyrus infection, despite the ongoing parasitism. Goblet cell mucins that reacted with PGM34 increased on the ileal mucosa during V. nana parasitism. Small intestinal goblet cells reacting with the two mAbs were not observed in non-infected mice, although sialomucins and sulfomucins were abundantly present. Additionally, the number of ileal goblet cells that reacted with the two mAbs was increased at the time of expulsion of heterophyid trematode. These results indicate that the type of specific acidic mucins expressed after infection varies among species of intestinal helminth, and, furthermore, that the relationship with worm expulsion is also different.