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Mucosal interactions with enteropathogenic bacteria
Published in Phillip D. Smith, Richard S. Blumberg, Thomas T. MacDonald, Principles of Mucosal Immunology, 2020
Nadine Cerf-Bensussan, Pamela Schnupf, Valérie Gaboriau-Routhiau, Philippe J. Sansonetti
In order to adhere to epithelium, enteropathogens express a large variety of cell-surface adhesins, including polymeric fimbriae and afimbrial adhesins. Some pathogens such as Yersinia spp. and Listeria spp. can harness host transmembrane cell-adhesion receptors and trigger intracellular cascades that lead to epithelial cell invasion. Other invasive bacteria, such as Shigella and Salmonella, use their T3SS to inject bacterial effectors and induce the formation of a macropinocytic pocket, which enables phagocytic uptake.
Unexplained Fever Associated with Diseases of the Gastrointestinal Tract
Published in Benedict Isaac, Serge Kernbaum, Michael Burke, Unexplained Fever, 2019
Recently recognized pathogens Yersinia and Campylobacter may cause febrile diarrhea or may simulate inflammatory bowel disease or even acute appendicitis. In Yersinia enteritis45,46 the most important symptoms are fever, abdominal pain, and diarrhea. Fever occurs in approximately 50% of cases and may vary from high temperatures of brief duration to low-grade fever lasting for weeks. Campylobacter enteritis47,48 is characterized by a prodromal stage of fever, malaise, abdominal pain, nausea, and myalgia, followed by diarrhea, which may be bloody. The condition usually subsides in 3 to 4 days, but in debilitated or im-munosuppressed patients, it can become severe and prolonged or relapsing. Other manifestations and methods of diagnosis of these infections are discussed elsewhere (see Chapter 20).
Gastroenterology
Published in Stephan Strobel, Lewis Spitz, Stephen D. Marks, Great Ormond Street Handbook of Paediatrics, 2019
Most commonly, children present with acute selflimiting diarrhoea. γ enterocolitica can cause fever and cramping abdominal pain, mimicking acute appendicitis. It is the commonest bacterial aetiology of intussusception. Ultrasound examination can differentiate between them. Chronic diarrhoea may ensue, possibly with erythema nodosum and arthritis. Infection may mimic CD. Isolation of Yersinia has been difficult, but a PCR-based assay may be feasible. Colonoscopy findings may mimic CD with mucosal thickening of the terminal ileum, aphthous ulcers and nodularity.
Re-establishing the utility of tetracycline-class antibiotics for current challenges with antibiotic resistance
Published in Annals of Medicine, 2022
Kerry L. LaPlante, Abhay Dhand, Kelly Wright, Melanie Lauterio
Tetracycline-class drugs inhibit bacterial protein synthesis by binding to bacterial ribosomes and interacting with the highly conserved 16S ribosomal RNA (rRNA) in the 30S ribosomal subunit [6]. The drug class demonstrates a broad spectrum of activity against a wide range of gram-positive, gram-negative, and atypical pathogens, resulting in the extensive use of the tetracycline class in both humans and animals after the drugs were initially discovered [5]. Indications for treatment of bacterial infections include pneumonia; skin infections; bone and joint infections; sexually transmitted infections including chlamydia, syphilis, and gonorrhoea; intra-abdominal infections; biothreat pathogens, including Yersinia pestis, Bacillus anthracis, and Francisella tularensis; and other specific bacterial pathogens such as Rickettsia spp, Borrelia spp, and nontuberculous mycobacteria. Tetracycline-class agents are recommended as first-line treatment options for many of these indications [7–13].
The relevance of studying insect–nematode interactions for human disease
Published in Pathogens and Global Health, 2022
Zorada Swart, Tuan A. Duong, Brenda D. Wingfield, Alisa Postma, Bernard Slippers
Knowledge on interspecies interactions gained from studying EPN systems is not limited to the field of nematode infections. The symbiotic bacteria of EPN represent as important models to study bacteria-host interactions, as nematode–host interactions [17]. Bacteria from the genera Photorhabdus and Xenorhabdus (the symbionts of Heterorhabditis and Steinernema, respectively) form part of the Enterobacteriaceae [75]. Other members of this family include the common human pathogens, Escherichia coli, Salmonella spp., Yersinia spp. and Proteus spp. In fact, Proteus mirabilis – one of the most common causative agents of urinary tract and hospital-acquired infections [76,77–78] – is the closest phylogenetic relative to Photorhabdus and Xenorhabdus. Therefore, an understanding of pathogenicity in the entomopathogenic bacteria can contribute to a search for similarities in human pathogens. The discovery of such orthologous virulence pathways could reveal strategies for the prevention and treatment of P. mirabilis infection in humans.
Yersinia pseudotuberculosis YopE prevents uptake by M cells and instigates M cell extrusion in human ileal enteroid-derived monolayers
Published in Gut Microbes, 2021
Alyssa C. Fasciano, Gaya S. Dasanayake, Mary K. Estes, Nicholas C. Zachos, David T. Breault, Ralph R. Isberg, Shumin Tan, Joan Mecsas
Even though transcytosis of WT 37°C was less frequent, it was still significantly detected in the presence of M cells compared to the absence, demonstrating that M cell-containing monolayers are required for detectable transcytosis in this model. Murine studies with T3SS mutants, such as yscNU, have shown that these bacteria are able to colonize PP but are far less likely to survive at 24 hours post-infection.39,68 Since the T3SS gives Yptb an advantage upon encountering immune cells,22 it is possible that the rare T3SS-expressing Yptb that breach M cells are ultimately more successful in animal infection. Alternatively, the successful bacteria may be those that are expressing low levels of Yops during encounter with M cells but are ramping up T3SS expression as they travel through the M cell. In fact, consistent with this idea, during infection Yersinia can respond rapidly to environmental cues, such as host cell contact, to increase the copy number of the plasmid carrying the T3SS, which is essential for virulence.71