Biology subjects

Zangara, M. T.

Publications and source records attributed to Zangara, M. T..

5 recordsLinked to original sources

bioRxiv2026

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↗

bioRxiv2025

A Saccharomyces boulardii synthetic biotic platform for delivery of therapeutic nanobodies to ameliorate gastrointestinal inflammation

Protein-based pharmaceuticals, such as engineered antibodies, form a major drug class of steadily increasing market share. However, these biologic medicines are costly to manufacture, are subject to strict supply chain and storage constraints and often require invasive administration routes. Engineered microbes that secrete bioactive products directly within the microbiome milieu may mitigate these challenges. Here, we describe a cell microfactory platform based on the probiotic yeast Saccharomyces boulardii for the production of nanobody biologics in the gastrointestinal (GI) tract. High-level secretion of nanobodies by S. boulardii was achieved by optimizing promoters, secretion signals, and antibody formats. In mice, oral gavage of S. boulardii allowed efficient and transient colonization of the colonic compartment and in situ production of a therapeutic nanobody directed against tumor necrosis factor (TNF). In a mouse model of chemical-induced colitis, GI-delivery of anti-mTNF nanobody via live S. boulardii improved both survival and disease severity without causing overt perturbation of microbiome composition. These results position S. boulardii as a synthetic biotic platform for the in situ production and delivery of protein-based therapeutics to the GI tract.

synthetic biology↗

bioRxiv2022

N-phosphonacetyl-L-aspartate enhances type I interferon anti-viral responses through activation of non-canonical NOD2 signaling

Type I interferon production and the expression of interferon-stimulated genes (ISGs) are key components of an innate immune response to many microbial pathogens. Dysregulation of this response can result in uncontrolled infection, inflammation, and autoimmune disease. Understanding the molecular mechanisms shaping the strength of type I interferon signaling may provide critical insights into infection control strategies and autoimmune disease therapies. Nucleotide-binding oligomerization domain 2 (NOD2) is an intracellular pattern recognition receptor that acts as both a bacterial sensor protein and a mediator of antiviral responses. Antibacterial functions of NOD2 are enhanced by treatment with the small molecule inhibitor of pyrimidine biosynthesis N-phosphonacetyl-L-aspartate (PALA), though how this might function in the host antiviral response remains unknown. Therefore, we tested the ability of PALA to enhance NOD2-dependent antiviral responses. Alone, PALA treatment of macrophages was not sufficient to induce interferon {beta} (IFN{beta}) production or ISG expression. Instead, PALA synergized with IFN{beta} stimulation to enhance expression and activation of interferon-stimulated gene factor 3 (ISGF3) and induce the upregulation of a subset of ISGs in co-treated cells. Furthermore, PALA treatment of epithelial cells resulted in impaired viral replication of the herpesvirus, human cytomegalovirus. Induction of the PALA-enhanced antiviral response required activation of non-canonical NOD2 signaling mediated by mitochondrial antiviral-signaling protein (MAVS) and interferon response factor 1 (IRF1), rather than the classical receptor-interacting serine/threonine protein kinase 2 (RIP2) pathway or other IRFs previously reported to mediate NOD2 antiviral responses. These findings highlight pyrimidine metabolism enzymes as controllers of antimicrobial responses and suggest novel mechanisms for the modulation of type I interferon responses and antiviral activity. Significance StatementUnderstanding the molecular mechanisms shaping the strength of type I interferon signaling may provide critical insights to improve infection control strategies and autoimmune disease therapies. This work demonstrates that the pyrimidine synthesis inhibitor N-phosphonacetyl-L-aspartate synergizes with type I interferon to enhance antiviral responses through activation of a non-canonical NOD2 signaling pathway. These findings highlight pyrimidine metabolism enzymes as controllers of antimicrobial responses and suggest novel mechanisms for the modulation of type I interferon responses.

molecular biology↗

bioRxiv2021

A 3D printable device allowing fast and reproducible longitudinal preparation of mouse intestines

Accurate and reproducible analysis of mouse small and large intestinal lumen is key for research involving intestinal pathology in preclinical models. Currently, there is no easily accessible, standardized method that allows researchers of different skill levels to consistently dissect intestines in a time-efficient manner. Here, we describe the design and use of the 3D printed "Mouse Intestinal Slicing Tool" (MIST), which can be used to longitudinally prepare murine intestines for further analysis. We benchmarked the MIST against a commonly used procedure involving scissors to make a longitudinal cut along the intestines. Use of the MIST halved the time per mouse to prepare the intestines and outperformed alternative methods in smoothness of the cutting edge and general reproducibility. By sharing the plans for printing the MIST, we hope to contribute a uniformly applicable method for saving time and increasing consistency in studies of the mouse gastrointestinal tract.

pathology↗

bioRxiv2021

Development of a Reproducible Porcine Model of Infected Burn Wounds

Severe burns are traumatic and physically debilitating injuries with a high rate of mortality. Bacterial infections often complicate burn injuries, which presents unique challenges for wound management and improved patient outcomes. Currently, pigs are used as the gold standard of pre-clinical models to study infected skin wounds due to the similarity between porcine and human skin in terms of structure and immunological response. However, utilizing this large animal model for wound infection studies can be technically challenging and create issues with data reproducibility. We present a detailed protocol for a porcine model of infected burn wounds based on our experience in creating and evaluating partial thickness burn wounds infected with Staphylococcus aureus on six pigs. Wound healing kinetics and bacterial clearance were measured over a period of 27 days in this model. Enumerated are steps to achieve standardized wound creation, bacterial inoculation, and dressing techniques. Systematic evaluation of wound healing and bacterial colonization of the wound bed is also described. Finally, advice on animal housing considerations, efficient bacterial plating procedures, and overcoming common technical challenges is provided. This protocol aims to provide investigators with a step-by-step guide to execute a technically challenging porcine wound infection model in a reproducible manner. Accordingly, this would allow for the design and evaluation of more effective burn infection therapies leading to better strategies for patient care. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=103 SRC="FIGDIR/small/456568v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@1d00970org.highwire.dtl.DTLVardef@11bb8caorg.highwire.dtl.DTLVardef@10110d0org.highwire.dtl.DTLVardef@f6d89d_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗