Bacterial Infection of Pancreatic Necrosis: Role of Bacterial Translocation, Impact of Antibiotic Treatment

Pancreatology ◽  
2001 ◽  
Vol 1 (2) ◽  
pp. 79-89 ◽  
Author(s):  
R. Isenmann ◽  
H.G. Beger
2017 ◽  
Vol 5 (3) ◽  
pp. 397-398
Author(s):  
Anastasiya Atanasova Chokoeva ◽  
Georgi Tchernev

A 28-year-old male patient, presented with a one-week history of pain and itching on the skin of the left upper leg. Erythematous indurated, warm and painful on palpation, subcutaneous plaques and nodules were clinically observed, affecting the skin of the left upper leg, within a recent black-wolf tattoo. The diagnosis of traumatic panniculitis with superposed bacterial infection, provoked by a wolf tattoo was made.  The patient underwent 7-days systemic antibiotic treatment regimen and topical application of iodine povidone unguent under occlusion for 7 days. Significant alleviation of the subjective complaints was achieved within the first week, with a total clinical resolution of the symptoms. The role of the procedure as a source of trauma for subcutaneous inflammation (traumatic panniculitis) and the contamination of the equipment or the staff (infective panniculitis) in simultaneously triggering of the pathogenetic chain of the reported Wolf’s panniculitis could be present.


Cells ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 959 ◽  
Author(s):  
Jefferson Antônio Leite ◽  
Gabriela Pessenda ◽  
Isabel C. Guerra-Gomes ◽  
Alynne Karen Mendonça de Santana ◽  
Camila André Pereira ◽  
...  

Pattern recognition receptors (PRRs), such as Nod2, Nlrp3, Tlr2, Trl4, and Tlr9, are directly involved in type 1 diabetes (T1D) susceptibility. However, the role of the cytosolic DNA sensor, AIM2, in T1D pathogenesis is still unknown. Here, we demonstrate that C57BL/6 mice lacking AIM2 (AIM2−/−) are prone to streptozotocin (STZ)-induced T1D, compared to WT C57BL/6 mice. The AIM2−/− mice phenotype is associated with a greater proinflammatory response in pancreatic tissues, alterations in gut microbiota and bacterial translocation to pancreatic lymph nodes (PLNs). These alterations are related to an increased intestinal permeability mediated by tight-junction disruption. Notably, AIM2−/− mice treated with broad-spectrum antibiotics (ABX) are protected from STZ-induced T1D and display a lower pancreatic proinflammatory response. Mechanistically, the AIM2 inflammasome is activated in vivo, leading to an IL-18 release in the ileum at 15 days after an STZ injection. IL-18 favors RegIIIγ production, thus mitigating gut microbiota alterations and reinforcing the intestinal barrier function. Together, our findings show a regulatory role of AIM2, mediated by IL-18, in shaping gut microbiota and reducing bacterial translocation and proinflammatory response against insulin-producing β cells, which ultimately results in protection against T1D onset in an STZ-induced diabetes model.


Hepatology ◽  
2016 ◽  
Vol 64 (2) ◽  
pp. 508-521 ◽  
Author(s):  
Raluca Wroblewski ◽  
Marietta Armaka ◽  
Vangelis Kondylis ◽  
Manolis Pasparakis ◽  
Henning Walczak ◽  
...  

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yamaguchi R ◽  
◽  
Sakamoto A ◽  
Haraguchi M ◽  
Narahara S ◽  
...  

The pathogenesis of pulmonary fibrosis remains unknown. However, bacterial infections in patients with idiopathic pulmonary fibrosis are a serious complication that exacerbate the disease. Serum levels of Surfactant Protein D (SPD) are known to be elevated in patients with pulmonary fibrosis, but the role of SPD in pulmonary fibrosis complicated with bacterial infection is unknown. Lipopolysaccharide upregulates Interleukin (IL)-12p40 expression and IL-12p40 promotes Interferon Gamma (IFNγ) production to induce the T helper cell 1 (Th1) immune response via Signal Transducers and Activators of Transcription 4 (STAT4) signaling. A lack of IFNγ shifts the immune response from Th1 to Th2. IL-4 is a profibrotic Th2 cytokine that activates fibroblasts. Granulocyte-macrophage colony-stimulating factor induced by IL-1 and TNFα during the Th1 immune response upregulates Signal Regulatory Protein α (SIRPα) expression. Interferon Regulatory Factor 1 (IRF1) functions as the promoter activator of IL-12p40 after stimulation with LPS. SPD is a ligand for SIRPα, and SPD/SIRPα ligation activates the Mitogen-Activated Protein Kinase (MAPK)/Extracellular Signal-Related Kinase (ERK) signal cascade; ERK downregulates Interferon Regulatory Factor 1 (IRF1) expression. Consequently, the SPD/SIRPα signaling pathway decreases IL-12p40 production in human macrophages after exposure to LPS. IL-12p40 is a key immunoregulatory factor in bacterial infection that promotes production of IFNγ by T lymphocytes. Pulmonary fibroblasts are activated by IL-4/IL-4R ligation. IFNγ induces IRF1 via STAT1 signaling, and IRF1 acts as the promoter repressor of IL-4 to attenuate its production. IFNγ also inhibits IL-4R expression. A reduction in IFNγ induced by IL-12p40 deficiency via the SPD/SIRPα signaling pathway enhances IL-4 and IL-4R expression to augment the activity of fibroblasts. This finding indicates that pulmonary fibrosis is exacerbated by SPD/SIRPα signaling during bacterial infection.


2001 ◽  
Vol 69 (11) ◽  
pp. 6660-6669 ◽  
Author(s):  
Ichiro Tatsuno ◽  
Masanori Horie ◽  
Hiroyuki Abe ◽  
Takeyoshi Miki ◽  
Kozo Makino ◽  
...  

ABSTRACT Adherence of enterohemorrhagic Escherichia coli (EHEC) to the intestinal epithelium is critical for initiation of a bacterial infection. An in vitro infection study previously indicated that EHEC bacteria initially adhere diffusely and then proliferate to develop MC, a process that is mediated by various secreted proteins, such as EspA, EspB, EspD, Tir, and intimin, as well as other putative adherence factors. In the present study, we investigated the role of a large 93-kb plasmid (pO157) in the adherence of O157:H7 (O157Sakai) and found the toxB gene to be involved in the full adherence phenotype. A pO157-cured strain of O157Sakai (O157Cu) developed microcolonies on Caco-2 cells; however, the number of microcolonies was lower than that of O157Sakai, as were the production and secretion levels of EspA, EspB, and Tir. Introduction of a mini-pO157 plasmid (pIC37) composed of thetoxB and ori regions restored full adherence capacity to O157Cu, including production and secretion of the proteins. In contrast, introduction of a pO157 mutant possessingtoxB::Km into O157Cu could not restore the full adherence phenotype. Expression of truncated versions of His-tagged ToxB also promoted EspB production and/or secretion by O157Cu. These results suggest that ToxB contributes to the adherence of EHEC to epithelial cells through promotion of the production and/or secretion of type III secreted proteins.


2020 ◽  
Author(s):  
Xiao-Ting Zhang ◽  
Yong-Yao Yu ◽  
Hao-Yue Xu ◽  
Zhen-Yu Huang ◽  
Xia Liu ◽  
...  

AbstractThe skin of vertebrates is the outermost organ of the body and serves as the first line of defense against external aggressions. In contrast to mammalian skin, that of teleost fish lacks keratinization and has evolved to operate as a mucosal surface containing a skin-associated lymphoid tissue (SALT). Thus far, IgT representing the prevalent immunoglobulin (Ig) in SALT have only been reported upon infection with a parasite. However, very little is known about the types of B cells and Igs responding to bacterial infection in the teleost skin mucosa, as well as the inductive or effector role of the SALT in such responses. To address these questions, here we analyzed the immune response of trout skin upon infection with one of the most widespread fish skin bacterial pathogens, Flavobacterium columnare. This pathogen induced strong skin innate immune and inflammatory responses at the initial phases of infection. More critically, we found that the skin mucus of fish having survived the infection contained significant IgT-but not IgM- or IgD-specific titers against the bacteria. Moreover, we demonstrate the local proliferation and production of IgT+ B-cells and specific IgT titers respectively within the SALT upon bacterial infection. Thus, our findings represent the first demonstration that IgT is the main Ig isotype induced by the skin mucosa upon bacterial infection, and that because of the large surface of the skin, its SALT probably represents a prominent IgT inductive site in fish.


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