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Biology subjects

Tertigas, D.

Publications and source records attributed to Tertigas, D..

3 recordsLinked to original sources

Peyer's patches are a niche for antibiotic-driven expansion of Crohn's disease-associated adherent-invasive Escherichia coli

Antibiotic exposure is a significant risk factor for Crohns disease, yet the tissue-specific consequences of antibiotic-driven dysbiosis remain poorly defined. Adherent-invasive Escherichia coli (AIEC), a pathobiont enriched in Crohns disease, expands following antibiotic treatment, but whether discrete mucosal niches support this expansion is unknown. Peyers patches are specialized lymphoid structures that coordinate mucosal immunity and are frequently associated with early disease lesions, suggesting they may represent a vulnerable site for pathobiont colonization. Here, we show that vancomycin disrupts the Peyers patch-associated microbiome, creating a permissive niche that is selectively exploited by AIEC and associated with focal inflammation. Antibiotic treatment markedly increased AIEC burden within Peyers patches. AIEC localized within the lymphoid follicle was accompanied by focal tissue pathology and a distinct cytokine signature. In contrast, expansion of resident E. coli in the absence of AIEC did not elicit comparable inflammation, indicating that the pathogenic traits of AIEC are required to trigger disease-relevant responses in this niche. Supporting this, genetic disruption of flagellin, long polar fimbriae, or antimicrobial peptide resistance in AIEC attenuated Peyers patch colonization or inflammation, revealing separable mechanisms governing niche access and immunopathology. Together, these findings identify Peyers patches as a previously unrecognized reservoir for antibiotic-driven AIEC expansion and define a localized host-microbe interaction that links dysbiosis to focal intestinal inflammation. These results provide a mechanistic framework for understanding how antibiotic exposure may precipitate site-specific pathology in Crohns disease. Further, these findings highlight that mucosal lymphoid tissues should be considered when evaluating microbiome-targeted therapeutic interventions in Crohns disease.

microbiology↗

Cis-aconitate therapy protects against influenza mortality by dual targeting of viral polymerase and ERK/AKT/NF-κB signaling

Influenza virus poses a significant global health challenge, causing approximately 500,000 deaths annually. Its ability to evade antiviral treatments and vaccine-induced immunity underscores the need for novel therapeutic approaches. Our study identifies cis-aconitate (cis-aco), a mitochondria-derived metabolite, as a potent dual-action agent against influenza, independently of its metabolic derivative, itaconate. Cis-aco impairs viral polymerase activity, suppressing viral mRNA expression and protein synthesis to inhibit replication across a range of influenza subtypes. This antiviral efficacy is confirmed in ex vivo human airway and lung organotypic models. Beyond its antiviral properties, cis-aco exhibits potent anti-inflammatory effects, disrupting key inflammatory cascades and reducing the secretion of inflammatory mediators. In a mouse model of influenza pneumonia, cis-aco mitigates viral replication, inflammation, and immune cell activation, significantly improving survival. Notably, its efficacy persists even when administered at later stages of infection, when oseltamivir/Tamiflu(R) is no longer effective. These findings position cis-aco as a promising influenza treatment, combining antiviral and anti-inflammatory benefits within a clinically relevant timeframe.

immunology↗

In mouse and gut-on-a-chip models, pre-colonoscopy bowel preparation promotes pathogen colonization of the gut and translocation to other organs

In the United States an estimated 14 million colonoscopies are performed yearly, each requiring patients to undergo bowel preparation, a laxative cleansing of the intestines luminal contents. Despite its widespread use, the effects of bowel preparation on gut physiology and susceptibility to pathogens remains poorly understood, particularly in individuals with compromised gut health. Using mouse and in vitro models, we found that bowel preparation with the laxative polyethylene glycol (PEG) rapidly disrupts, transiently increasing susceptibility to infection by Salmonella Typhimurium, including a non-motile mutant, and by gut pathobionts derived from ulcerative colitis microbiota. Bowel preparation also facilitated bacterial translocation to extraintestinal sites (mesenteric lymph nodes, liver, and spleen) and exacerbated inflammation in a chemically-induced colitis model. Although these findings are preclinical, they suggest that bowel preparation may have underappreciated risks in vulnerable populations, and warrant further clinical investigation.

microbiology↗