scholarly journals The Exopolysaccharide of Lactobacillus fermentum UCO-979C Is Partially Involved in Its Immunomodulatory Effect and Its Ability to Improve the Resistance against Helicobacter pylori Infection

2020 ◽  
Vol 8 (4) ◽  
pp. 479
Author(s):  
Valeria Garcia-Castillo ◽  
Guillermo Marcial ◽  
Leonardo Albarracín ◽  
Mikado Tomokiyo ◽  
Patricia Clua ◽  
...  

Lactobacillus fermentum UCO-979C (Lf979C) beneficially modulates the cytokine response of gastric epithelial cells and macrophages after Helicobacter pylori infection in vitro. Nevertheless, no in vivo studies were performed with this strain to confirm its beneficial immunomodulatory effects. This work evaluated whether Lf979C improves protection against H. pylori infection in mice by modulating the innate immune response. In addition, we evaluated whether its exopolysaccharide (EPS) was involved in its beneficial effects. Lf979C significantly reduced TNF-α, IL-8, and MCP-1 and augmented IFN-γ and IL-10 in the gastric mucosa of H. pylori-infected mice. The differential cytokine profile induced by Lf979C in H. pylori-infected mice correlated with an improved reduction in the pathogen gastric colonization and protection against inflammatory damage. The purified EPS of Lf979C reduced IL-8 and enhanced IL-10 levels in the gastric mucosa of infected mice, while no effect was observed for IFN-γ. This work demonstrates for the first time the in vivo ability of Lf979C to increase resistance against H. pylori infection by modulating the gastric innate immune response. In addition, we advanced knowledge of the mechanisms involved in the beneficial effects of Lf979C by demonstrating that its EPS is partially responsible for its immunomodulatory effect.

2020 ◽  
Vol 10 (1) ◽  
pp. 187-192
Author(s):  
O. V. Smirnova ◽  
A. A. Sinyakov

At present, the level of Helicobacter pylori infection is determined by geographic area, gender and age of the examined individuals, and can reach up to 95% of the total population. Environmental adaptation of H. pylori is exhibited in its ability to adhere to the gastric mucosal epithelium and modulated expression of its own virulent factors. Current concepts implicate that H. pylori can survive inside epithelial cells, evading host immune response. Cytokines are produced by immune cells and act to regulate its major stages. A cytokine cascade launched after Helicobacter pylori infection triggers immune reactions, progression of chronic inflammatory and destructive processes in the gastric mucosa. The role of cytokines in precancerous diseases of the stomach is ambiguous because, on the one hand, they activate immune response aimed at eliminating the pathogen, whereas on the other hand, they do contribute to the disease progression. The aim of our study was to examine profile of some cytokines and features of cytokine regulation in H. pylori-infected middle-aged males with chronic gastritis (CG) as well as chronic atrophic gastritis (CAG). In patients with CG with H. pylori, CAG and CAG with H. pylori, an increase in the cytokine IL-2 was observed that might contribute to augmented damaging effect of cytotoxic lymphocytes, as well as implementation of antitumor effect. CAG with H. pylori was featured with IL-8 hyperproduction, which resulted in increased absolute numbers of band neutrophils in peripheral blood and their decreased phagocytic activity evidencing about altered host defense mechanisms. There was increased amount of IFNy involved in recognition of malignantly transformed cells and upregulated expression of the major histocompatibility complex molecules on antigen-presenting cells. In patients with CG with H. pylori and CAG with H. pylori, production of IL-4 was increased, which might serve as a contributing factor to the chronicity of H. pylori-associated diseases. Overproduction of type 1 and type 2 cytokines indicates about activated Th1 and Th2 type immune reactions in H. pylori-associat-ed CG. A potent pro-inflammatory cytokine cascade triggers inflammatory changes in gastric mucosa with developing neutrophil infiltration and lymphocyte activation. Damage and death of epithelial cells upon inflammation form erosive and ulcerative defects, or changes manifested as gastric mucosal atrophy, metaplasia and neoplasia. The data obtained may be used as additional diagnostic criteria in early diagnostics of precancerous stomach diseases.


2021 ◽  
Vol 9 (6) ◽  
pp. 1324
Author(s):  
Fernanda Raya Tonetti ◽  
Mikado Tomokiyo ◽  
Ramiro Ortiz Moyano ◽  
Sandra Quilodrán-Vega ◽  
Hikari Yamamuro ◽  
...  

Previously, we demonstrated that the nasal administration of Dolosigranulum pigrum 040417 differentially modulated the respiratory innate immune response triggered by the activation of Toll-like receptor 2 in infant mice. In this work, we aimed to evaluate the beneficial effects of D. pigrum 040417 in the context of Streptococcus pneumoniae infection and characterize the role of alveolar macrophages (AMs) in the immunomodulatory properties of this respiratory commensal bacterium. The nasal administration of D. pigrum 040417 to infant mice significantly increased their resistance to pneumococcal infection, differentially modulated respiratory cytokines production, and reduced lung injuries. These effects were associated to the ability of the 040417 strain to modulate AMs function. Depletion of AMs significantly reduced the capacity of the 040417 strain to improve both the reduction of pathogen loads and the protection against lung tissue damage. We also demonstrated that the immunomodulatory properties of D. pigrum are strain-specific, as D. pigrum 030918 was not able to modulate respiratory immunity or to increase the resistance of mice to an S. pneumoniae infection. These findings enhanced our knowledge regarding the immunological mechanisms involved in modulation of respiratory immunity induced by beneficial respiratory commensal bacteria and suggested that particular strains could be used as next-generation probiotics.


mBio ◽  
2017 ◽  
Vol 8 (4) ◽  
Author(s):  
Alevtina Gall ◽  
Ryan G. Gaudet ◽  
Scott D. Gray-Owen ◽  
Nina R. Salama

ABSTRACT Helicobacter pylori is a bacterial pathogen that colonizes the human stomach, causing inflammation which, in some cases, leads to gastric ulcers and cancer. The clinical outcome of infection depends on a complex interplay of bacterial, host genetic, and environmental factors. Although H. pylori is recognized by both the innate and adaptive immune systems, this rarely results in bacterial clearance. Gastric epithelial cells are the first line of defense against H. pylori and alert the immune system to bacterial presence. Cytosolic delivery of proinflammatory bacterial factors through the cag type 4 secretion system ( cag -T4SS) has long been appreciated as the major mechanism by which gastric epithelial cells detect H. pylori . Classically attributed to the peptidoglycan sensor NOD1, recent work has highlighted the role of NOD1-independent pathways in detecting H. pylori ; however, the bacterial and host factors involved have remained unknown. Here, we show that bacterially derived heptose-1,7-bisphosphate (HBP), a metabolic precursor in lipopolysaccharide (LPS) biosynthesis, is delivered to the host cytosol through the cag -T4SS, where it activates the host tumor necrosis factor receptor-associated factor (TRAF)-interacting protein with forkhead-associated domain (TIFA)-dependent cytosolic surveillance pathway. This response, which is independent of NOD1, drives robust NF-κB-dependent inflammation within hours of infection and precedes NOD1 activation. We also found that the CagA toxin contributes to the NF-κB-driven response subsequent to TIFA and NOD1 activation. Taken together, our results indicate that the sequential activation of TIFA, NOD1, and CagA delivery drives the initial inflammatory response in gastric epithelial cells, orchestrating the subsequent recruitment of immune cells and leading to chronic gastritis. IMPORTANCE H. pylori is a globally prevalent cause of gastric and duodenal ulcers and cancer. H. pylori antibiotic resistance is rapidly increasing, and a vaccine remains elusive. The earliest immune response to H. pylori is initiated by gastric epithelial cells and sets the stage for the subsequent immunopathogenesis. This study revealed that host TIFA and H. pylori -derived HBP are critical effectors of innate immune signaling that account for much of the inflammatory response to H. pylori in gastric epithelial cells. HBP is delivered to the host cell via the cag -T4SS at a time point that precedes activation of the previously described NOD1 and CagA inflammatory pathways. Manipulation of the TIFA-driven immune response in the host and/or targeting of ADP-heptose biosynthesis enzymes in H. pylori may therefore provide novel strategies that may be therapeutically harnessed to achieve bacterial clearance.


Cell Reports ◽  
2017 ◽  
Vol 20 (10) ◽  
pp. 2384-2395 ◽  
Author(s):  
Stephanie Zimmermann ◽  
Lennart Pfannkuch ◽  
Munir A. Al-Zeer ◽  
Sina Bartfeld ◽  
Manuel Koch ◽  
...  

2021 ◽  
Author(s):  
Ana Marina Andrei ◽  
Elena Cristina Andrei ◽  
Elena Camelia Stănciulescu ◽  
Mihaela Cezarina Mehedinți ◽  
Mihaela Jana Țuculină ◽  
...  

Gingivitis and periodontitis are induced by numerous pathogenic microbiota hosted in the subgingival biofilm that first trigger the innate immune response. Innate immune response is part of a homeostatic system which is the first line defence and defines the host inherited resistance to infection. Both genetic and environmental factors are involved in variable individual susceptibility to inflammation of periodontal tissues. That is why, although more than 600 bacterial species have been detected in the periodontal plaque, the type of bacteria incriminated in the development of the inflammation is still unclear. Moreover, in the last decade gene polymorphisms have been largely recognised as important conditions associated with increased susceptibility to periodontal diseases. Manipulating the immune response by the development of drugs that inhibit adverse host reactions and promote beneficial effects might be of therapeutic or prophylactic importance. This work intends to assess the importance of Toll-like receptors as main effectors of the innate immune response in the triggering, maintenance and progression of periodontal inflammation, as well as of the involvement of synthetic molecules targeting TLR signalling pathways in treating periodontal diseases.


Author(s):  
R. I. Khlynova ◽  
O. M. Khromtsova ◽  
R. B. Berdnikov ◽  
I. B. Khlynov

The aim is to study the effect of Helicobacter pylori infection on risk of developing gastroesophageal reflux disease. Materials and methods - cross-sectional observational study of 1007 patients with dyspepsia syndrome who underwent videoesophagogastroduodenoscopy with biopsy and histological examination of biopsy specimens of the gastric mucosa by OLGA-system. The age, gender, overweight, cigarette smoking, presence of Helicobacter pylori infection and gastritis stage were assessed. Results - the study showed a significant decrease in the incidence of gastroesophageal reflux disease in patients with positive H. Pylori status by 4% (RR 0,68; 95% CI, 0.49-0.94, p=0,041). The risk of developing gastroesophageal reflux disease significantly higher in overweight (RR 2,62; 95% CI 2,0-3,56; р<0,001) men (RR 1,76; 95% CI 1,33-2,32; р=0,0046) who smoked cigarettes (RR 3,23; 95% CI 2,45-4,24; р<0,001) and was not associated with the patient’s age and the stage of gastritis (р>0,05). Conclusion - a significant reduction in the frequency and risk of developing gastroesophageal reflux disease in patients with Helicobacter pylori infection is demonstrated.


2018 ◽  
Vol 9 (5) ◽  
pp. 829-841 ◽  
Author(s):  
V. Garcia-Castillo ◽  
H. Zelaya ◽  
A. Ilabaca ◽  
M. Espinoza-Monje ◽  
R. Komatsu ◽  
...  

Helicobacter pylori infection is associated with important gastric pathologies. An aggressive proinflammatory immune response is generated in the gastric tissue infected with H. pylori, resulting in gastritis and a series of morphological changes that increase the susceptibility to cancer development. Probiotics could present an alternative solution to prevent or decrease H. pylori infection. Among them, the use of immunomodulatory lactic acid bacteria represents a promising option to reduce the severity of chronic inflammatory-mediated tissue damage and to improve protective immunity against H. pylori. We previously isolated Lactobacillus fermentum UCO-979C from human gastric tissue and demonstrated its capacity to reduce adhesion of H. pylori to human gastric epithelial cells (AGS cells). In this work, the ability of L. fermentum UCO-979C to modulate immune response in AGS cells and PMA phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 (human monocytic leukaemia) macrophages in response to H. pylori infection was evaluated. We demonstrated that the UCO-979C strain is able to differentially modulate the cytokine response of gastric epithelial cells and macrophages after H. pylori infection. Of note, L. fermentum UCO-979C was able to significantly reduce the production of inflammatory cytokines and chemokines in AGS and THP-1 cells as well as increase the levels of immunoregulatory cytokines, indicating a remarkable anti-inflammatory effect. These findings strongly support the probiotic potential of L. fermentum UCO-979C and provide evidence of its beneficial effects against the inflammatory damage induced by H. pylori infection. Although our findings should be proven in appropriate experiments in vivo, in both H. pylori infection animal models and human trials, the results of the present work provide a scientific rationale for the use of L. fermentum UCO-979C to prevent or reduce H. pylori-induced gastric inflammation in humans.


2020 ◽  
Vol 88 (6) ◽  
Author(s):  
Jenessa A. Winston ◽  
Alissa J. Rivera ◽  
Jingwei Cai ◽  
Rajani Thanissery ◽  
Stephanie A. Montgomery ◽  
...  

ABSTRACT Clostridioides difficile infection (CDI) is associated with increasing morbidity and mortality posing an urgent threat to public health. Recurrence of CDI after successful treatment with antibiotics is high, thus necessitating discovery of novel therapeutics against this enteric pathogen. Administration of the secondary bile acid ursodeoxycholic acid (UDCA; ursodiol) inhibits the life cycles of various strains of C. difficile in vitro, suggesting that the FDA-approved formulation of UDCA, known as ursodiol, may be able to restore colonization resistance against C. difficile in vivo. However, the mechanism(s) by which ursodiol is able to restore colonization resistance against C. difficile remains unknown. Here, we confirmed that ursodiol inhibits C. difficile R20291 spore germination and outgrowth, growth, and toxin activity in a dose-dependent manner in vitro. In a murine model of CDI, exogenous administration of ursodiol resulted in significant alterations in the bile acid metabolome with little to no changes in gut microbial community structure. Ursodiol pretreatment resulted in attenuation of CDI pathogenesis early in the course of disease, which coincided with alterations in the cecal and colonic inflammatory transcriptome, bile acid-activated receptors nuclear farnesoid X receptor (FXR) and transmembrane G-protein-coupled membrane receptor 5 (TGR5), which are able to modulate the innate immune response through signaling pathways such as NF-κB. Although ursodiol pretreatment did not result in a consistent decrease in the C. difficile life cycle in vivo, it was able to attenuate an overly robust inflammatory response that is detrimental to the host during CDI. Ursodiol remains a viable nonantibiotic treatment and/or prevention strategy against CDI. Likewise, modulation of the host innate immune response via bile acid-activated receptors FXR and TGR5 represents a new potential treatment strategy for patients with CDI.


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