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Objective: Cytokines initiate and modify systemic inflammatory response in early acute pancreatitis. The aim of this study was to analyze which cytokines are released from the pancreas to portal venous blood in the early phase of acute experimental necrotizing and oedematous pancreatitis and which of those cytokines are correlated with the more severe form of the disease., Material and Methods: Fifteen pigs were randomized to develop mild oedematous pancreatitis (n = 5, saline infusion to pancreatic duct), severe necrotizing pancreatitis (n = 5, taurocholic acid infusion) along with a control group (n = 5). Arterial and venous blood samples were drawn and cytokine levels were measured from portal vein blood at 0, 120, 240 and 360 min after the induction of pancreatitis. Tissue samples from the pancreas were harvested at 0 and 360 min., Results: White blood cell count increased in necrotizing pancreatitis and the control group. The amount of neutrophils increased (p < 0.001) and the lymphocyte and eosinophil counts decreased in all groups (p < 0.001, p < 0.001). The monocyte count, as well as PDGF and IL-6 concentrations, increased only in necrotizing pancreatitis. IL-8 and eotaxin increased both in oedematous and necrotizing pancreatitis. MCP-1 increased in all groups. IL-9, IL-4, MIP-1α, IFN- γ concentrations did not change. Eotaxin and MCP-1 plasma levels from a previous series between portal venous and pulmonary arterial blood were not significantly different., Conclusions: The initial inflammatory process was diverse in oedematous and necrotizing pancreatitis. Increased monocyte count in combination with elevated PDGF and IL-6 are characteristic of necrotizing pancreatitis in our model.

Background: Cow's milk protein allergy (CMPA) is the most prevalent food allergy in children, and its pathogenesis remains poorly understood. It has been shown that the combination of genetic predisposition, perinatal factors, and intestinal imbalance of the immune response mediated by cytokines may play an essential role in CMPA pathogenesis., Aim: To characterize the gene expression of Th1, Th2, and Th17 cytokines in the duodenum and rectum in patients with CMPA., Methods: This is an observational, descriptive, cross-sectional, prospective study. We used specific IgE (ImmunoCAP ® ) in serum and biopsies from the rectum and duodenum for the detection of cytokine messenger RNA levels by real-time PCR in patients with a positive oral food challenge for CMPA. We analyzed the relative quantification of the gene expression of cytokines by real-time PCR, and we used the housekeeping gene GAPDH for normalization purposes., Results: Thirty children (13 male and 17 female) were evaluated. All patients had an open challenge for CMPA. IgE specific to casein, alfa-lactalbumin, and beta-lactoglobulin was negative in all patients. In terms of cytokine levels, the levels of TNFα, IL-6, IL-12 (Th1), IL-4, IL-10, IL-13 (Th2), and IL-17 were found to be higher in the rectum than in the duodenum (p < 0.05). IL-15 was found to be higher in the duodenum than in the rectum (p < 0.05)., Conclusions: In the present study we observed that the immune response in CMPA seems to be mediated by a Th1, Th2, and Th17 cytokine profile, with the rectum being the main affected site., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

We aimed to study intestinal immune activation status in juvenile idiopathic arthritis ( JIA) by assessing intestinal human leucocyte antigen ( HLA) class II expression and the mRNA expression levels of the pro- and anti-inflammatory mediators and pattern recognition receptors. HLA- D-related ( HLA-DR) expression was assessed using immunohistochemical staining of frozen sections in 11 children with JIA and 17 controls. The gene expression levels of the anti- and proinflammatory cytokines, lymphocyte recognition receptors and pattern recognition receptors were studied with reverse transcription-polymerase chain reaction ( RT- PCR) in 14 children with JIA and 12 controls. All subjects had various gastrointestinal ( GI) symptoms indicating endoscopic examinations, but eventually were not diagnosed with GI disease. In JIA patients, the expression of HLA- DR was increased in the crypt epithelial cells and in the epithelial basement membrane of the ileum when compared with the controls. Positive HLA- DR staining in the ileal mucosa was associated with the presence of high clinical disease activity of JIA and low mRNA expression of anti-inflammatory mediators, such as forkhead box protein P3 ( FoxP3), glucocorticoid-induced tumour necrosis factor receptor-related protein ( GITR) and transforming growth factor ( TGF)-beta. Low ileal expression of interleukin ( IL)-10, TGF-β, FoxP3, Toll-like receptor 2 ( TLR-2) and TLR-4 transcripts correlated significantly with a high clinical disease activity in the JIA patients. The increased HLA- DR expression suggests enhanced intestinal antigen presentation in JIA. A correlation between clinical disease activity and low gene expression of tolerogenic mediators in the ileum supports the hypothesis that a link exists between the gut immune system and JIA. [ABSTRACT FROM AUTHOR]

Background:Inflammation contributes to the pathogenesis of colorectal cancer (CRC), and cytokine levels are altered during colorectal carcinogenesis.Methods:The serum levels of 13 cytokines and their relation to clinical and pathological parameters, and systemic inflammatory response (mGPS, CRP and neutrophil-lymphocyte ratio), were analysed from a prospective series of 148 CRC patients and 86 healthy age- and sex-matched controls.Results:CRC patients had higher serum platelet-derived growth factor, interleukin (IL)-6, IL-7, and IL-8 levels and lower monocyte chemotactic protein-1 (MCP-1) levels than the controls. A logistic regression model for discriminating the patients from the controls - including the five most predictive cytokines (high IL-8, high IL-6, low MCP-1, low IL-1ra, and low IP-10) - yielded an area under curve value of 0.890 in receiver operating characteristics analysis. Serum cytokines showed distinct correlation with other markers of systemic inflammatory response, and advanced CRCs were associated with higher levels of IL-8, IL-1ra, and IL-6. A metastasised disease was accompanied by an orientation towards Th2 cytokine milieu.Conclusion:CRC is associated with extensive alterations in serum cytokine environment, highlighting the importance of studying relative cytokine level alterations. Serum cytokine profile shows promise in separating CRC patients from healthy controls but its clinical value is yet to be confirmed. [ABSTRACT FROM AUTHOR]

A response from the author of the article "Stage-dependent alterations of the serum cytokine pattern in colorectal carcinoma" in the previous issue is presented.

Gastroduodenitis caused by H. pylori, often acquired in early childhood, is found in about 50% of the adult population. Although H. pylori infections can remain asymptomatic, its virulence factors usually trigger epithelial vacuolization and degeneration, loss of microvilli, disintegration of cytoplasm, and leukocyte accumulation. It is believed that leukocyte infiltration is driven by cytokines produced locally in infected tissue. However, so far little is known about changes in serum cytokines in juvenile patients infected with H. pylori. Serum cytokine profiles were analyzed in 62 juvenile patients diagnosed with gastroduodenitis using the Bio-Plex multiplex assay. H. pylori infection was confirmed in 32 patients, while 30 patients were H. pylori-free. Cytokines CXCL5 and CXCL6, potent neutrophil chemoattractants, were upregulated in all patients diagnosed with gastroduodenitis. Serum levels of IL8, a prototype neutrophil attractant, remained unchanged in subjects with gastroduodenitis relative to controls. Therefore, our data suggest that CXCL5 and CXCL6 play a role in directing neutrophil trafficking into inflamed gastroduodenal tissue. In addition, the CCL25/GM-CSF ratio differed significantly between H. pylori-positive and -negative juveniles. Further, study is needed to evaluate the role of CCL25 and GM-CSF in the pathogenesis of the different etiologies of gastroduodenitis. [ABSTRACT FROM AUTHOR]

Peptic ulcer disease (PUD) is a chronic disease based on recurrent gastric or duodenal ulcers. Association analysis of common polymorphisms of the cytokines genes IL1B ( rs1143634), IL1RN ( rs71941886), IL8 ( rs4073), IL10 ( rs1800872), and TNFA ( rs1800629) was conducted in 254 patients with gastric ulcer or duodenal ulcer and in 277 unrelated healthy individuals from the Bashkortostan Republic. Associations of the rs1143634*C allele and the C/ C genotype of the IL1B gene with PUD in ethnic Bashkirs have been revealed. The frequency of the rs4073*A/ A genotype of the IL8 gene was significantly higher in the control group as compared to patients infected with H. pylori. Our results confirm the significant role of rs1143634 of the IL1B gene in PUD development. [ABSTRACT FROM AUTHOR]

Both Th1 and Th17 cells are important components of the immune response to Helicobacter pylori (Hp) in adults, but less is known about T cell responses to Hp during early childhood, when the infection is often acquired. We investigated Th1 and Th17 type responses to Hp in adults, children and infants in Bangladesh, where Hp is highly endemic. IL-17 and IFN-γ mRNA levels in gastric biopsies from Hp-infected Bangladeshi adults were analyzed and compared to levels in infected and uninfected Swedish controls. Since biopsies could not be collected from infants and children, cytokine responses in Bangladeshi infants (6–12 months), children (3–5 years) and adults (>19 years) were instead compared by stimulating peripheral blood mononuclear cells (PBMCs) with a Hp membrane preparation (MP) and analyzing culture supernatants by ELISA and cytometric bead array. We found significantly higher expression of IL-17 and IFN-γ mRNA in gastric mucosa of Hp-infected Bangladeshi and Swedish adults compared to uninfected Swedish controls. PBMCs from all age groups produced IL-17 and IFN-γ after MP stimulation, but little Th2 cytokines. IL-17 and IFN-γ were primarily produced by CD4+ T cells, since CD4+ T cell depleted PBMCs produced reduced amounts of these cytokines. Infant cells produced significantly more IL-17, but similar levels of IFN-γ, compared to adult cells after MP stimulation. In contrast, polyclonal stimulation induced lower levels IL-17 and IFN-γ in infant compared to adult PBMCs and CD4+ T cells. The strong IL-17 production in infants after MP stimulation was paralleled by significantly higher production of the IL-17 promoting cytokine IL-1β from infant compared to adult PBMCs and monocytes. In conclusion, these results show that T cells can produce high levels of IL-17 and IFN-γ in response to Hp from an early age and indicate a potential role for IL-1β in promoting Th17 responses to Hp during infancy. [ABSTRACT FROM AUTHOR]

Background Helicobacter pylori ( Hp)-related gastritis is characterized by a predominant T helper ( Th)1/ Th17 cell immunity. Ghrelin ( GR) has immunoregulatory properties and inhibits experimental Th cell-dependent pathology. Aims To evaluate whether Hp infection associates with changes in GR expression and whether GR negatively regulates Th1/ Th17 cytokines during Hp infection. Methods GR expression was evaluated by real-time PCR in gastric biopsies taken from Hp-infected and Hp-uninfected patients and in gastric biopsies of Hp-negative subjects cultured with or without H. pylori culture supernatant. To examine whether GR regulates Hp-induced cytokine production, H. pylori-infected gastric biopsies were stimulated with GR, and interleukin ( IL)-12, interferon ( IFN)-γ and IL-4 transcripts were evaluated by real-time PCR. IL-12 and IFN-γ were also analyzed in lamina propria mononuclear cells ( LPMCs) extracted from Hp-infected gastric biopsies and cultured with GR. Results GR RNA transcripts were reduced in biopsies from Hp-infected patients. Treatment of Hp-negative gastric biopsies with Hp culture supernatant reduced GR RNA expression. GR dose-dependently inhibited RNA expression of IL-12 and IFN-γ but not IL-4 in ex vivo cultures of mucosal explants and in cultures of gastric LPMCs from Hp-positive patients. Conclusions GR is downregulated in the gastric mucosa of H. pylori-infected patients. Such a defect could contribute to sustain the ongoing Th1-cell response. [ABSTRACT FROM AUTHOR]

Non steroidal anti-inflammatory drugs (NSAIDs) induce gastric mucosal lesions in part by induction of oxidative stress as well as the activation of inflammatory cells and the production of proinflammatory cytokines. In this study, we examined the protective effect of candesartan (2 and 5 mg/kg) on indomethacin-induced gastric mucosa damage. Pretreatment with candesartan for 10 days reduced significantly the ulcer index induced by indomethacin injection. The preventive index of 2 mg/kg (76.74%) was higher than that of 5 mg/kg (65.11%). Both doses of candesartan were able to reduce significantly the stomach malondialdehyde content compared to indomethacin-treated group. Myeloperoxidase, tumor necrosis factor-α, cytokine-induced neutrophil chemoattractant gastric levels were significantly reduced by 2 mg/kg of candesartan more than 5 mg/kg. The Th1 cytokine interferon γ was also significantly reduced by both doses of candesartan compared to indomethacin injected group. On the other hand, indomethacin significant decreased the anti-inflammatory cytokine IL-10 gastric level. Pretreatment with candesartan (2 and 5 mg/kg) reversed this effect. In conclusion, the present study indicates that pretreatment with candesartan, can protect against the stomach injury induced by indomethacin through its antioxidant and immunomodulatory effects. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is a gram-negative micro-aerophilic bacterium that is widely distributed geographically and causes chronic gastritis, peptic ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. Bacterial virulence factors play an important role, since the virulent strains are more aggressive and increase the risk of developing severe clinical manifestations; in addition, other determinant factors are the nutritional state and the immune response of the host. Studies on humans, non-human primates, and rodents have reported that regulating proteins of the Th1 phenotype predominate in the immune response to the bacterial infection. The cytokines produced by this phenotype, are not very effective in eradicating the microorganism and furthermore, contribute to gastro-duodenal pathogenesis. Gastric inflammation in patients infected with H. pylori has been characterized by increased production of IL-1, IL-6, IL-12, IL-18, TNF-α, and IFN-γ. Many prophylactic and therapeutic strategies have been researched using experimental animals. The utilization and effectiveness of vaccination on humans requires more study. [ABSTRACT FROM AUTHOR]

Background. Regulatory T cells (known as "Treg") express apyrases (CD39) and ecto-5'-nucleotidase (CD73) and contribute to their inhibitory function by generating adenosine. We investigated the expression of CD39 and CD73 on human T helper (Th) cells and the role of CD73 in regulating Helicobacter felis-induced gastritis and colonization. Methods. Human CD4+ Th cells, gastric T cells, or Treg subsets were stimulated and assayed for the expression of CD39 and CD73 by means of reverse-transcriptase polymerase chain reaction and flow cytometry. The effect of CD73 on proliferation and cytokine production was assessed, and the presence of gastritis, proinflammatory cytokine expression, or colonization of H. felis was evaluated in CD73-deficient (CD73-/-) mice or recipient mice given control or CD73-/- Treg. Results. CD4+ T cells expressed CD39 and CD73, particularly in CD25+Foxp3+ Treg from peripheral blood or gastric mucosa. Activation significantly increased CD73 expression on all Th cells. Inhibition of CD73 enhanced production of interferon-γ. Gastritis in H. felis-infected CD73-/- mice was significantly worse than that in wild-type mice and was accompanied by increased levels of proinflammatory cytokines and reduced bacterial colonization, whereas Treg from CD73-/- mice did not inhibit gastritis. Conclusion. CD39 and CD73 expressed by Th cells contribute to local accumulation of adenosine and attenuation of gastritis, which may favor persistent infection. [ABSTRACT FROM AUTHOR]

Abstract  IgA antibodies to tissue transglutaminase have been suggested to be specific indicators of celiac disease. However, no studies have addressed the relationships between such antibodies and alcohol abuse, which is also a common cause of IgA-isotype immune responses and tissue injury in the gastrointestinal tract and liver. Here, measurements of specific IgAs against tissue transglutaminase and proteins modified by acetaldehyde, the first metabolite of ethanol, showed significantly higher levels of both antibodies in alcoholic liver disease patients than in healthy controls or heavy drinkers without liver disease. These antibodies also significantly co-occurred in heavy drinkers without liver disease, moderate drinkers, and abstainers, and correlated with biomarkers of alcohol consumption, proinflammatory cytokines and markers of fibrogenesis. The data suggests a link between such immune responses, perturbations in cytokine profiles and fibrogenesis, which should be implicated in studies on the pathogenesis and diagnosis of ethanol-induced tissue injury and celiac disease. [ABSTRACT FROM AUTHOR]

Background. The cytokines induced by Helicobacter pylori, as well as the intricate balance of proinflammatory and anti-inflammatory cytokines, are relevant to the outcomes of H. pylori infection. Transforming growth factor (TGF)-β and interleukin (IL)-10 are 2 vital anti-inflammatory cytokines that regulate mucosal immunity in various inflammatory and infectious diseases. Methods. To elucidate whether host-bacteria interaction can influence TGF-β and IL-10 production, we investigated the expression of TGF-β and IL-10 in various mammalian cell lines preincubated with H. pylori and other enteric bacteria. Results. The amount of TGF-β protein, but not IL-10, was significantly increased after stimulation with H. pylori, but other enteric bacteria did not induce TGF-β production. Different H. pylori strains isolated from patients with gastritis, peptic ulcer, gastric cancer and strains with cagA or vacA isogenic mutations showed similar effects on TGF-β induction, indicating that this effect was a constitutional characteristic of H. pylori and independent of cagA and vacA status. Conclusion. The results imply the presence of a protein factor (termed ‘TGF-β-inducing protein’) that induces production of TGF-β. In view of the multiple effects of TGF-β, we conclude the TGF-β-inducing protein of H. pylori might mediate the immune response and contribute to the pathogenesis of H. pylori infection. [ABSTRACT FROM AUTHOR]

Colonization with Helicobacter pylori always results in chronic gastritis, which is controlled by infiltration of mononuclear cells and the subsequent release of cytokines like interleukin (IL)-12. To identify H. pylori factors involved in inducing cytokine production in mononuclear cells, a random H. pylori mutant library was screened for the inability to induce IL-12 production in monocyte THP-1 cells. Of the 231 random mutants screened, one mutant (M1) showed a consistent twofold decrease in the amount of IL-12 induction compared to the parental strain 1061 (P<0.01). Further characterization of mutant M1 revealed that the kanamycin resistance cassette had integrated in the jhp0945 gene, which is situated in an H. pylori strain-specific plasticity region. Three reference strains possessing this plasticity region induced significantly higher amounts of IL-12 when compared to the H. pylori 26695 reference strain, which does not possess this plasticity region. The role in disease outcome of jhp0945 as well as the neighbouring plasticity region genes jhp0947 and jhp049 was assessed in a Dutch population cohort. Firstly, the presence of jhp0947 was completely linked with that of jhp0949 and was roughly associated with jhp0945 (P=0.072), but not with the cag pathogenicity island (PAI) (P=0.464). The presence of the jhp0947 and jhp0949 genes, but not of jhp0945, was significantly associated with duodenal ulcer disease when compared to gastritis (P=0.027). Therefore, the jhp0947–jhp0949 locus may be a novel putative H. pylori marker for disease outcome independent of the cag PAI. [Copyright &y& Elsevier]

Aim: Few studies have looked at the cytokine profile in gastric mucosa in children with Helicobacter pylori infection. This study investigated cytokines and their effects on histological abnormalities in the gastric mucosa of children with H. pylori infection.Methods: The levels of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and IL-8 proteins were measured in biopsy specimens from the gastric antrum and corpus of children with H. pylori infection, and related to inflammatory cell infiltrations.Results: The antral and corporal mucosal levels of IFN-gamma and IL-8 proteins were significantly higher in children with H. pylori infection than in uninfected children, but there was no such difference in the levels of IL-4 protein. The antral mucosal level of IL-8 protein was significantly higher than the corporal mucosal level of IL-8 protein in the infected children. Inflammatory cell infiltration was significantly higher in the infected children than in the uninfected children, but there were no significant correlations between mucosal cytokine levels and inflammatory cell infiltrations.Conclusion: The results suggest that the predominant Th1 cytokine response and enhanced IL-8 production in the mucosa may be involved in the gastric inflammation seen in children infected with H. pylori, as well as in adult patients. [ABSTRACT FROM AUTHOR]

Background: Increased collagen and extracellular matrix deposition within the gingiva is the main characteristic feature of hereditary gingival fibromatosis (HGF). To date, it is not well established if these events are a consequence of alterations in the collagen and other extracellular matrix molecules synthesis or disturbances in the homeostatic equilibrium between synthesis and degradation of extracellular matrix molecules. Cytokines are important regulators of expression of the profibrogenic genes, including type I collagen and its molecular chaperone heat shock protein (Hsp)47 and proteolytic enzymes degrading extracellular matrix such as matrix metalloproteinases-1 and -2 (MMP-1 and MMP-2}. Methods: In this study, we analyzed the expression and production of type I collagen, Hsp47, MMP-1, and MMP-2 in normal gingiva (NG) and HGF fibroblasts, and investigated the effects of transforming growth factor-beta1 (TGF-β1), interleukin-6 (1L-6) and interferon-gamma (IFN-γ) on the expression of these genes by NG and HGF fibroblasts. Results: Our results obtained from semi-quantitative reverse transcription-polymerase chain reactions (RT-PCR), Western blots, enzyme-linked immunosorbent assays (ELISA), and enzymographies clearly demonstrated that the expression and production of type I collagen and Hsp47 were significantly higher in fibroblasts from HGF than from NG, whereas MMP-1 and MMP-2 expression and production were lower in fibroblasts from HGF patients. Addition of TGF-β1 and IL-6, which are produced in greater amounts by HGF fibroblasts, promoted an increase in type I collagen and Hsp47 and a decrease in MMP-1 and MMP-2 expression. IFN-γ reduced both type I collagen and Hsp47 expression, whereas it had a slight effect on the expression of MMP-1 and MMP-2. Conclusion: These patterns of expression and production suggest that enhanced TGF-β1 and IL-6 production simultaneously increase the synthesis and reduce the proteolytic activities of fibroblasts from patients with HGF, which may favor the accumulation of extracellular matrix observed in patients with this condition. [ABSTRACT FROM AUTHOR]

Background: Gingival overgrowth is a common side effect following the administration of cyclosporin A (CsA). The pathogenesis of this condition is not fully understood; however, recent studies show that CsA regulates the transcription of several cytokines including transforming growth factor-β1 (TGF-β1). The aim of this study was to investigate the potential role of TGF-βl in the pathogenesis of CsA-induced gingival overgrowth, exploring a possible autocrine stimulation of TGF-β1 as a cellular regulator of synthesis of matrix metalloproteinases (MMPs) and its tissue inhibitors (TIMPs). Methods: Gingival fibroblasts from human normal gingiva were incubated with increasing concentrations of CsA, cultured for 24 hours, and the expression and production of TGF-β1 determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. MMP and TIMP mRNA expression levels were also analyzed by RT-PCR. To determine the effect of TGF-βl on the expression of MMP and TIMP by human gingival fibroblasts under CsA treatment, human gingival fibroblast cultures were treated with sense oligonucleotidcs (SON) or anti-sense oligonucleotides (AON). Results: CsA simultaneously stimulated TGF-β1 expression and production and inhibited expression of MMP-1 and MMP-2 by human gingival fibroblasts, whereas CsA has a slight effect on TIMP-1 and TIMP-2 expression AON reduced TGF-β1 production as demonstrated by ELISA, whereas TGF-β1 mRNA expression levels were not significantly modified. The inhibition of TGF-β1 production by AON modulated MMP expression, demonstrating the autocrine inhibitory effect of TGF-β1 in CsA-treated human gingival fibroblasts. Conclusions: The data presented here suggest that TGF-β1 in an autocrine fashion may contribute to a reduction of proteolytic activity of human gingival fibroblasts in CsA-induced gingival overgrowth, which favors the accumulation of extracellular matrix. [ABSTRACT FROM AUTHOR]

Approximately 50% of humanity is infected with Helicobacter pylori. This lifelong infection elicits a marked host response, including a robust gastric IgA response. However, natural infection fails to yield protective immunity. Rather than providing protection, the chronic inflammatory response associated with natural infection can contribute to tissue damage and the pathogenesis of gastroduodenal disease, including atrophic gastritis, peptic ulcer, and gastric cancer. These immune responses are attributed to a subset of helper T cells, so-called Th1 cells, that enhance cell-mediated immunity and induce damage to the gastric epithelium. Thus, it is desirable to have effective vaccines that could prevent and cure infection and that may modify the host response in a manner that prevents immune-mediated disease. Using animal models as a tool to understand the immunobiology of Helicobacter infections, several investigators have shown that effective vaccines can be developed. Thus, prophylactic and even therapeutic vaccines have been described in various animal models. The basis for the effectiveness of these vaccines appears related to their ability to alter the gastric immune response, from a homogeneous Th1 response to a mixed Th1 and Th2 response. Interestingly, immunity can occur in the absence of B cells, suggesting that novel IgA-independent mechanisms exist that confer protection against a luminal infection. Thus, H. pylori infection provides a model with which new mechanisms of immunological protection can be identified and applied to other mucosal infections. [ABSTRACT FROM AUTHOR]

The pathophysiology of hypergastrinemia in H. pylori infection has been largely investigated and different reports clearly show that the infected antrum has a marked inflammatory response with a suggestive local production of cytokines. Notwithstanding, a few data are available on the circulating levels of cytokines and gastrin in the asymptomatic people carrying H. pylori infection. Thus, aim of the study was to evaluate circulating proinflammatory cytokines [Interleukin (IL)-8, Interleukin (IL)-10, Interferon (IFN)-γ, and Tumor Necrosis Factor (TNF)-α] and gastrin levels in H. pylori positive asymptomatic subjects vs. H. pylori negative ones. To this end, thirty healthy volunteers with no digestive symptoms or systemic disease were enrolled and H. pylori infection was identified by a [sup 13]C-urea breath test. Plasma levels of gastrin were determined using the RIA kit whereas IL-8, TNF-α, IL-10, and IFN-γ levels in serum were measured with a solid-phase ELISA. Fifteen infected people showed significantly higher gastrin and TNF-α levels than uninfected subjects. On the contrary, IL-8 levels were significantly higher in the uninfected sub- jects than in H. pylori positive ones (P < 0.0422). IFN-γ and IL-10 circulating levels were not affected by H. pylori presence, being not significantly different in the two groups. [ABSTRACT FROM AUTHOR]

In order to characterize T cell responses in human Helicobacter pylori infection, we have examined proliferative responses and cytokine production by CD4+ and CD8+ T cells isolated from duodenal ulcer patients and asymptomatic H. pylori carriers, after activation with some H. pylori antigens that may be important in disease development. For control purposes, T cells from uninfected volunteers were also examined. The different H. pylori antigens induced only modest proliferative responses in circulating CD4+ and CD8+ T cells from both H. pylori-infected and uninfected individuals. However, circulating T cells from H. pylori-infected subjects produced larger amounts of interferon-gamma (IFN-γ) in response to the Helicobacter antigens than did T cells from uninfected volunteers. Furthermore, CD8+ T cells produced larger amounts of IFN-γ than did CD4+ T cells, on a per cell basis. Most IFN-γ-producing cells from both infected and uninfected volunteers appeared to be naive T cells expressing CD45RA. Increased production of IL-4 and IL-5 was, on the other hand, only seen in a few instances after stimulation of isolated CD4+ and CD8+ T cells. Stimulation of freshly isolated gastric T cells with the different H. pylori antigens did not result in increased proliferation or cytokine production. In conclusion, our results show that several different purified H. pylori antigens induce production of IFN-γ, preferentially by CD8+ cells. Therefore, they suggest that IFN-γ-secreting CD8+ cells contribute significantly to the cytokine response induced by H. pylori infection. [ABSTRACT FROM AUTHOR]

Immediately after the Great Hanshin Earthquake in Kobe in 1995, the recurrence rate of peptic ulcer in patients infected with Helicobacter pylori was higher than that in patients in whom H. pylori had been eradicated. We evaluated the influence of H. pylori infection on stress-induced gastric mucosal injury in Mongolian gerbils and C57BL/6 mice. These animals were immersed in water for 30, 120, and 720 min 12 weeks after inoculation with H. pylori, and then killed to assess gastric mucosal damage, and to measure cytokine production (interleukin [IL]-1beta, IL-4, IL-6, and IL-10; interferon [IFN]-gamma; and tumor necrosis factor [TNF]-alpha) in the gastric tissue of the mice. The stress treatment for 30 min resulted in a significantly higher bleeding rate and bleeding index among infected gerbils and mice compared with results in uninfected animals. Conversely, the bleeding and ulcer indexes were significantly higher in uninfected gerbils after 720 min of the stress treatment than in infected gerbils. Prior to the stress treatment, gastric IL-1beta and IFN-gamma production was significantly higher in the infected group than in the uninfected group. After 120 min of the stress treatment, TNF-alpha production was increased in the infected group, and IL-1beta and IL-10 production was increased in the uninfected group. However, the production of these cytokines showed no change at 30 min of the stress treatment. These results suggest that H. pylori infection influences the development of gastric mucosal injury in the early phase of stress exposure; cytokines do not play a major role in this process. [ABSTRACT FROM AUTHOR]

AbstractBackground: Gastric mucosal injury by Helicobacter pylori has been suggested to be mediated by various cytokines induced by this organism. Nitric oxide (NO) is an important effector molecule involved in immune regulation and defence. To clarify the mechanisms by which H. pylori induces gastric mucosal cell injury, we examined whether H. pylori induces gastric epithelial death via NO production. Methods: Cytotoxic and non-cytotoxic strains of H. pylori were used. The death of MKN45 cells caused by H. pylori was examined by the 3-(4,5-dimethyl-thiazole-2yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Aminoguanidine was used to inhibit inducible nitric oxide synthase (iNOS) activity. Expression of iNOS mRNA was determined by the reverse transcriptase–polymerase chain reaction and the DNA fragmentation analysis was performed by using agarose gel electrophoresis. Results: The MTT assay revealed that neither viable H. pylori nor other components of the microorganism induced cell death. Both preincubation of MKN45 cells with interferon-γ for 6 h and coculture with TNF-α significantly increased the cytotoxicity of H. pylori. Both cytotoxic and non-cytotoxic strains of H. pylori induced cell death. Expression of iNOS mRNA was observed in MKN45 cells at 6, 8 and 12 h after H. pylori inoculation. The cytotoxicity of H. pylori was inhibited by aminoguanidine and DNA fragmentation analysis showed that H. pylori induced apoptosis. Conclusions: These findings suggested that viable H. pylori induces apoptosis of gastric epithelial cells via nitric oxide. Our study indicated that iNOS expression plays an important role in gastric cell injury. [ABSTRACT FROM AUTHOR]

Background: Between peripheral blood and tissue-infiltrating lymphocytes there is an intermediate compartment, the blood of the organ-draining vessels, which could show unusual features. The aim of the present study was to analyse the characteristics of the lymphocytes from the stomach-draining vessels and the cytokine secretion by these lymphocytes. The CagA-mediated lymphocyte activation in Helicobacter pylori-infected subjects and the humoral response to this antigen were evaluated and correlated with clinical data. Methods: We studied lymphocyte proliferation either with mitogens or with the CagA antigen and cytokine production and IgG anti-CagA by means of an enzyme-linked immunosorbent assay in peripheral blood and gastric-vein blood obtained during surgical intervention. Results: We showed higher proliferative response and cytokine production in lymphocytes from the gastric vein. The mitogenic response to the CagA antigen was highly specific but poorly sensitive for the H. pylori infection in both the compartments. The overall cytokine profile in our patients affected by non-ulcer disease was of the Th0 type. Conclusions: Gastric-vein-derived lymphocytes seem to show unusual features, as they behave like peripheral blood lymphocytes but show higher responses to all the tested stimuli. It is possible that the interaction of the lymphocytes with the mucosal environment could activate the synthetic mechanisms, making the cells more `responsive' to the stimulation. The CagA antigen is able to induce a specific T-lymphocyte response and is therefore a valid candidate antigen for the development of a vaccine. [ABSTRACT FROM AUTHOR]

Helicobacter pylori infection is associated with chronic infiltration by various cell types, including T cells, whose cytokine production may regulate the inflammatory reaction as well as local immune response to the bacterium. We prospectively analyzed the constituents of the cellular infiltrates and the cytokines produced by T cells in antral biopsies obtained from 73 subjects with and without H. pylori infection, before and after eradication therapy, and compared them with a histological grade of gastritis. We found that T cells predominated in cell number, followed by granulocytes/monocytes and plasma cells in both H. pylori-infected and H. pylori-uninfected subjects. Despite the absence of H. pylori infection, more than 70% of gastric CD4-positive T cells obtained from uninfected tissue produced interferon-gamma (IFN-gamma) in the cytosol. Upon receptor cross-linking of a CD3 and a CD28 molecule, T cells in both infected and uninfected tissue continuously secreted a far greater amount of IFN-gamma than those in peripheral blood mononuclear cell controls for a period of cell culture, whereas the increase in interleukin-4 (IL-4) was very small, and no increase in IL-2 secretion was seen. In H. pylori-infected patients, IFN-gamma secretion was correlated with the grade of mononuclear cell infiltration and decreased to an uninfected control level after eradication therapy. We did not see the effect of eradication on IL-4 secretion. Anti-H. pylori antibody of the IgG2 subclass was remarkably increased in H. pylori-infected subjects. These results together suggest that gastric T cells are already differentiated to produce a large amount of IFN-gamma by a mechanism unrelated to H. pylori infection. H. pylori infection appeared to activate T cells to secrete even more IFN-gamma, which may contribute to maintaining a perpetual inflammation in H. pylori-infected stomach. [ABSTRACT FROM AUTHOR]

A whole inactivated H. pylori bacterium preparation was found to stimulate blood mononuclear cells from both antibody-positive and antibody-negative subjects, but the antibody-positive subjects tended to have lower proliferation responses. The present study was designed to characterize T cell activation further by measuring several components of the response. Eighty-seven subjects (80 dyspeptic patients and seven healthy persons from the laboratory staff) with or without antibodies to H. pylori were studied by measuring the DNA synthesis induced by several H. pylori concentrations (1-23 μg/ml) and the control stimulants PPD, tetanus toxoid and pokeweed mitogen (PWM). H. pylori-induced secretion of interleukin-2 (IL-2), tumour necrosis factor-alpha (TNF-α), interleukin-4 (IL-4), soluble CD8 and IL-2 receptor (IL-2R) molecules and H. pylori- and PPD-induced appearances of IL-2R+ and HLA-DR+ T cells were measured in a smaller number of subjects. H. pylori-induced DNA synthesis was again lower in the antibody/bacterium-positive subjects, while no differences between the two groups were found in cultures stimulated by unrelated antigens or PWM. Soluble IL-2R and TNF-α were detectable in cultures with H. pylori from all subjects, while the amount of IL-2 did not differ from that in the background culture. No differences were found in the amounts of IL-2 or soluble IL-2R between the antibody-positive and negative subjects; while the former tended to secrete more soluble CD8 molecules, a difference which was significant with the smaller H. pylori concentration used (P < 0.01). The numbers of HLA-DR+ and IL-2R+ T cells increased in cultures with H. pylori or PPD from all the subjects, the majority of both cells having the CD4 phenotype. Numbers of DR+ and IL-2R+ T cells were similar in the cultures of the antibody-positive and negative subjects, but the respective CD8 subsets were increased in the former. The confirmed decrease in proliferation in the antibody-positive subjects does not seem to be connected with lower IL-2/IL-2R responses but may involve CD8 cell activation. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori infection contributes to hypergastrinemia and hypersecretion of acid by blocking inhibitory reflex pathways to gastrin and parietal cells normally activated by antral distention. Our aim was to investigate whether a similar blockade of inhibitory responses could be provoked by inducing gastritis with aspirin, thus implicating a common inflammatory component, possibly a proinflammatory cytokine(s). Methods: We studied the effects of antral distention on stimulated acid secretion and gastrin release in H. pylori-negative volunteers, before and after 3 days of aspirin therapy (2 g daily). Immediately before the examinations, the severity of gastric mucosal injury was evaluated macroscopically and histologically, and the production of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ was determined by immunohistochemistry. Results: Most subjects had severe gastric injury after aspirin therapy, resulting in a substantially increased production of IL-1β, IL-6, and IL-8 but not of TNF-α and IFN-γ in the antral mucosa. In these subjects the acid-inhibitory response was abolished or markedly reduced. Conversely, aspirin therapy failed to affect the gastrin release in all subjects studied. Conclusions: The disinhibition of acid secretion in response to antral distention is a joint feature of the gastritis induced by aspirin and H. pylori infection, possibly related to the increased production of IL-1β, IL-6, and IL-8. The H. pylori-related hypergastrinemia apparently has a different background. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is the cause of chronic type B gastritis and occurs in almost all patients with duodenal ulcers. Infection with H. pylori is characterized by an increased production of several inflammatory cytokines. Increasing evidence suggests a central role of these cytokines in the pathogenesis of H. pylori-associated gastritis and peptic ulcer disease. Cytokines may be crucial in the recruitment and activation of inflammatory cells and in stimulation of gastrin release. In addition to their proinflammatory properties, cytokines may also inhibit the ulcer occurrence by stimulation of prostaglandins and somatostatin release and by direct impairment of acid secretion. The balance of these factors may determine the clinical outcome of H. pylori infection. [ABSTRACT FROM AUTHOR]

Simple Summary: Glioblastoma (GBM) is the most lethal type of brain cancer. It is well known that the malignancy of cancers is dependent not only on the oncogenic properties of the tumor cells, but also on the composition of the tumor microenvironment, which includes macrophages of the immune system. The prevalence of M2 type macrophages usually promotes tumor progression as opposed to tumor-suppressing function of M1 type macrophages. In our previous studies, we identified Musashi-1 (MSI1) RNA-binding protein as a principal oncogenic factor in GBM. In this study, in a pursuit of finding secreted factors that may alter tumor microenvironment in GBM, we identified MIF1 cytokine to be positively regulated by MSI1. Moreover, we found that MSI1-mediated MIF1 secretion promotes differentiation of macrophages into pro-oncogenic M2 phenotype. The oncogenic role of MSI1/MIF1/M2 macrophage regulatory axis was also confirmed in GBM mouse models, which makes it a promising target for novel drug discovery. Glioblastoma (GBM) is the most malignant brain tumor which is characterized by high proliferation and migration capacity. The poor survival rate has been attributed to limitations of the current standard therapies. The search for novel biological targets that can effectively hamper tumor progression remains extremely challenging. Previous studies indicated that tumor-associated macrophages (TAMs) are the abundant elements in the tumor microenvironment that are closely implicated in glioma progression and tumor pathogenesis. M2 type TAMs are immunosuppressive and promote GBM proliferation. RNA-binding protein Musashi-1 (MSI1) has recently been identified as a marker of neural stem/progenitor cells, and its high expression has been shown to correlate with the growth of GBM. Nevertheless, the relationship between MSI1 and TAMs in GBM is still unknown. Thus, in our present study, we aimed to investigate the molecular interplay between MSI1 and TAMs in contributing to GBM tumorigenesis. Our data revealed that the secretion of macrophage inhibitory factor 1 (MIF1) is significantly upregulated by MSI1 overexpression in vitro. Importantly, M2 surface markers of THP-1-derived macrophages were induced by recombinant MIF1 and reduced by using MIF1 inhibitor (S,R)-3-(4-hHydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid (ISO-1). Furthermore, GBM tumor model data suggested that the tumor growth, MIF1 expression and M2 macrophage population were significantly downregulated when MSI1 expression was silenced in vivo. Collectively, our findings identified a novel role of MSI1 in the secretion of MIF1 and the consequent polarization of macrophages into the M2 phenotype in promoting GBM tumor progression. [ABSTRACT FROM AUTHOR]

Simple Summary: Malignant pleural mesothelioma (MPM) is a rare, biologically extremely aggressive tumor with an infaust prognosis. In this retrospective study, we aimed to assess the role of tumor-infiltrating immune cells and their activity in the respective histologic subtypes. We confirmed a substantial difference between epithelioid and sarcomatoid mesothelioma regarding the host's anti-cancer immune reaction. Whereas antigen processing and presentation to resident cytotoxic T cells as well as phagocytosis is highly affected in sarcomatoid mesothelioma, cell–cell interaction via cytokines seems to be of greater importance in epithelioid cases. Our work reveals the specific role of the immune system within the different histologic subtypes of MPM, providing a more detailed background of their immunogenic potential. This is of great interest regarding therapeutic strategies addressing immunotherapy in mesothelioma. Malignant pleural mesothelioma (MPM) is an aggressive malignancy associated with asbestos exposure. Median survival ranges from 14 to 20 months after initial diagnosis. As of November 2020, the FDA approved a combination of immune checkpoint inhibitors after promising intermediate results. Nonetheless, responses remain unsatisfying. Adequate patient stratification to improve response rates is still lacking. This retrospective study analyzed formalin fixed paraffin embedded specimens from a cohort of 22 MPM. Twelve of those samples showed sarcomatoid, ten epithelioid differentiation. Complete follow-up, including radiological assessment of response by modRECIST and time to death, was available with reported deaths of all patients. RNA of all samples was isolated and subjected to digital gene expression pattern analysis. Our study revealed a notable difference between epithelioid and sarcomatoid mesothelioma, showing differential gene expression for 304/698 expressed genes. Whereas antigen processing and presentation to resident cytotoxic T cells as well as phagocytosis is highly affected in sarcomatoid mesothelioma, cell–cell interaction via cytokines seems to be of greater importance in epithelioid cases. Our work reveals the specific role of the immune system within the different histologic subtypes of MPM, providing a more detailed background of their immunogenic potential. This is of great interest regarding therapeutic strategies including immunotherapy in mesothelioma. [ABSTRACT FROM AUTHOR]