scholarly journals Expansion of Paneth Cell Population in Response to Enteric Salmonella enterica Serovar Typhimurium Infection

2011 ◽  
Vol 80 (1) ◽  
pp. 266-275 ◽  
Author(s):  
Nadine R. Martinez Rodriguez ◽  
Marjannie D. Eloi ◽  
Alexandria Huynh ◽  
Teresa Dominguez ◽  
Annie H. Cheung Lam ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Cell Population ◽  
Salmonella Enterica ◽  
Paneth Cell ◽  
Paneth Cells ◽  
Differentiation Markers ◽  
Gastrointestinal Infections ◽  
Content Type ◽  
Serovar Typhimurium ◽  
Small Intestinal

ABSTRACTPaneth cells residing at the base of the small intestinal crypts contribute to the mucosal intestinal first line defense by secreting granules filled with antimicrobial polypeptides including lysozyme. These cells derive from the columnar intestinal stem cell located at position 0 and the transit amplifying cell located at position +4 in the crypts. We have previously shown thatSalmonella entericaserovar Typhimurium (ST), a leading cause of gastrointestinal infections in humans, effects an overall reduction of lysozyme in the small intestine. To extend this work, we examined small-intestinal tissue sections at various time points after ST infection to quantify and localize expression of lysozyme and assess Paneth cell abundance, apoptosis, and the expression of Paneth cell differentiation markers. In response to infection with ST, the intestinal Paneth cell-specific lysozyme content, the number of lysozyme-positive Paneth cells, and the number of granules per Paneth cell decreased. However, this was accompanied by increases in the total number of Paneth cells and the frequency of mitotic events in crypts, by increased staining for the proliferation marker PCNA, primarily at the crypt side walls where the transit amplifying cell resides and not at the crypt base, and by apoptotic events in villi. Furthermore, we found a time-dependent upregulation of first β-catenin, followed by EphB3, and lastly Sox9 in response to ST, which was not observed after infection with aSalmonellapathogenicity island 1 mutant deficient in type III secretion. Our data strongly suggest that, in response to ST infection, a Paneth cell differentiation program is initiated that leads to an expansion of the Paneth cell population and that the transit amplifying cell is likely the main progenitor responder. Infection-induced expansion of the Paneth cell population may represent an acute intestinal inflammatory response similar to neutrophilia in systemic infection.

scholarly journals Enteric Salmonella Infection Inhibits Paneth Cell Antimicrobial Peptide Expression

2003 ◽  
Vol 71 (3) ◽  
pp. 1109-1115 ◽  
Author(s):  
Nita H. Salzman ◽  
Margaret M. Chou ◽  
Hendrik de Jong ◽  
Lide Liu ◽  
Edith M. Porter ◽  
...  
Keyword(s):  
Type Iii Secretion ◽  
Paneth Cell ◽  
Paneth Cells ◽  
Enteric Pathogens ◽  
Intestinal Lumen ◽  
Oral Inoculation ◽  
Serovar Typhimurium ◽  
Peptide Expression ◽  
Small Intestinal ◽  
Antimicrobial Peptide Expression

ABSTRACT Paneth cells, highly secretory epithelial cells found at the bases of small intestinal crypts, release a variety of microbicidal molecules, including α-defensins and lysozyme. The secretion of antimicrobials by Paneth cells is thought to be important in mucosal host defense against invasion by enteric pathogens. We explored whether enteric pathogens can interfere with this arm of defense. We found that oral inoculation of mice with wild-type Salmonella enterica serovar Typhimurium decreases the expression of α-defensins (called cryptdins in mice) and lysozyme. Oral inoculation with Salmonella serovar Typhimurium strains that are heat killed, lack the PhoP regulon, and lack the SPI1 type III secretion system or with Listeria monocytogenes does not have this effect. Salmonella may gain a specific survival advantage in the intestinal lumen by decreasing the expression of microbicidal peptides in Paneth cells through direct interactions between Salmonella and the small intestinal epithelium.

scholarly journals Genetic Determinants of Salmonella enterica Serovar Typhimurium Proliferation in the Cytosol of Epithelial Cells

2016 ◽  
Vol 84 (12) ◽  
pp. 3517-3526 ◽  
Author(s):  
Marie Wrande ◽  
Helene Andrews-Polymenis ◽  
Donna J. Twedt ◽  
Olivia Steele-Mortimer ◽  
Steffen Porwollik ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Salmonella Enterica ◽  
Chloroquine Resistance ◽  
Intestinal Epithelial ◽  
Wild Type ◽  
Genetic Determinants ◽  
Gastrointestinal Infections ◽  
Content Type ◽  
Serovar Typhimurium ◽  
Infectious Cycle

Intestinal epithelial cells provide an important colonization niche forSalmonella entericaserovar Typhimurium during gastrointestinal infections. In infected epithelial cells, a subpopulation ofS. Typhimurium bacteria damage their internalization vacuole, leading to escape from theSalmonella-containing vacuole (SCV) and extensive proliferation in the cytosol. Little is known about the bacterial determinants of nascent SCV lysis and subsequent survival and replication ofSalmonellain the cytosol. To pinpointS. Typhimurium virulence factors responsible for these steps in the intracellular infectious cycle, we screened aS. Typhimurium multigene deletion library in Caco-2 C2Bbe1 and HeLa epithelial cells for mutants that had an altered proportion of cytosolic bacteria compared to the wild type. We used a gentamicin protection assay in combination with a chloroquine resistance assay to quantify total and cytosolic bacteria, respectively, for each strain. Mutants of threeS. Typhimurium genes,STM1461(ydgT),STM2829(recA), andSTM3952(corA), had reduced cytosolic proliferation compared to wild-type bacteria, and one gene,STM2120(asmA), displayed increased cytosolic replication. None of the mutants were affected for lysis of the nascent SCV or vacuolar replication in epithelial cells, indicating that these genes are specifically required for survival and proliferation ofS. Typhimurium in the epithelial cell cytosol. These are the first genes identified to contribute to this step of theS. Typhimurium infectious cycle.

scholarly journals IL-22 receptor signaling in Paneth cells is critical for their maturation, microbiota colonization, Th17-related immune responses, and anti-Salmonella immunity

2020 ◽  
Author(s):  
Stephen J. Gaudino ◽  
Michael Beaupre ◽  
Xun Lin ◽  
Preet Joshi ◽  
Sonika Rathi ◽  
...  
Keyword(s):  
Immune Responses ◽  
Host Defense ◽  
Knockout Mice ◽  
Paneth Cell ◽  
Cell Types ◽  
Paneth Cells ◽  
Lineage Tracing ◽  
Interleukin 22 ◽  
Serovar Typhimurium ◽  
Small Intestinal

Abstract Interleukin-22 (IL-22) signaling in the intestines is critical for promoting tissue-protective functions. However, since a diverse array of cell types (absorptive and secretory epithelium as well as stem cells) express IL-22Ra1, a receptor for IL-22, it has been difficult to determine what cell type(s) specifically respond to IL-22 to mediate intestinal mucosal host defense. Here, we report that IL-22 signaling in the small intestine is positively correlated with Paneth cell differentiation programs. Our Il22Ra1fl/fl;Lgr5-EGFP-creERT2-specific knockout mice and, independently, our lineage-tracing findings rule out the involvement of Lgr5+ intestinal stem cell (ISC)-dependent IL-22Ra1 signaling in regulating the lineage commitment of epithelial cells, including Paneth cells. Using novel Paneth cell-specific IL-22Ra1 knockout mice (Il22Ra1fl/fl;Defa6-cre), we show that IL-22 signaling in Paneth cells is required for small intestinal host defense. We show that Paneth cell maturation, antimicrobial effector function, expression of specific WNTs, and organoid morphogenesis are dependent on cell-intrinsic IL-22Ra1 signaling. Furthermore, IL-22 signaling in Paneth cells regulates the intestinal commensal bacteria and microbiota-dependent IL-17A immune responses. Finally, we show ISC and, independently, Paneth cell-specific IL-22Ra1 signaling are critical for providing immunity against Salmonella enterica serovar Typhimurium. Collectively, our findings illustrate a previously unknown role of IL-22 in Paneth cell-mediated small intestinal host defense.

scholarly journals Efficiency of Conditionally Attenuated Salmonella enterica Serovar Typhimurium in Bacterium-Mediated Tumor Therapy

mBio ◽  
2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Michael Frahm ◽  
Sebastian Felgner ◽  
Dino Kocijancic ◽  
Manfred Rohde ◽  
Michael Hensel ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Tumor Targeting ◽  
Antitumor Effect ◽  
Treatment Options ◽  
Tumor Therapy ◽  
Therapeutic Benefit ◽  
Industrialized Countries ◽  
Content Type ◽  
Serovar Typhimurium ◽  
Therapeutic Molecules

ABSTRACTIncreasing numbers of cancer cases generate a great urge for new treatment options. Applying bacteria likeSalmonella entericaserovar Typhimurium for cancer therapy represents an intensively explored option. These bacteria have been shown not only to colonize solid tumors but also to exhibit an intrinsic antitumor effect. In addition, they could serve as tumor-targeting vectors for therapeutic molecules. However, the pathogenicS. Typhimurium strains used for tumor therapy need to be attenuated for safe application. Here, lipopolysaccharide (LPS) deletion mutants (ΔrfaL, ΔrfaG, ΔrfaH, ΔrfaD, ΔrfaP, and ΔmsbBmutants) ofSalmonellawere investigated for efficiency in tumor therapy. Of such variants, the ΔrfaDand ΔrfaGdeep rough mutants exhibited the best tumor specificity and lowest pathogenicity. However, the intrinsic antitumor effect was found to be weak. To overcome this limitation, conditional attenuation was tested by complementing the mutants with an inducible arabinose promoter. The chromosomal integration of the respective LPS biosynthesis genes into thearaBADlocus exhibited the best balance of attenuation and therapeutic benefit. Thus, the present study establishes a basis for the development of an applicably cancer therapeutic bacterium.IMPORTANCECancer has become the second most frequent cause of death in industrialized countries. This and the drawbacks of routine therapies generate an urgent need for novel treatment options. Applying appropriately modifiedS. Typhimurium for therapy represents the major challenge of bacterium-mediated tumor therapy. In the present study, we demonstrated thatSalmonellabacteria conditionally modified in their LPS phenotype exhibit a safe tumor-targeting phenotype. Moreover, they could represent a suitable vehicle to shuttle therapeutic compounds directly into cancerous tissue without harming the host.

scholarly journals Whole-Genome Sequence of Salmonella enterica subsp. enterica Serovar Typhimurium Strain UPM 260, Isolated from a Broiler Chicken in Perak, Malaysia

2017 ◽  
Vol 5 (46) ◽  
Author(s):  
Najwa Syahirah Roslan ◽  
Shagufta Jabeen ◽  
Nurulfiza Mat Isa ◽  
Abdul Rahman Omar ◽  
Mohd Hair Bejo ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Salmonella Enterica ◽  
Broiler Chicken ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
Content Type ◽  
Typhimurium Strain ◽  
Serovar Typhimurium

ABSTRACT Salmonella enterica subsp. enterica serovar Typhimurium is one of several well-categorized Salmonella serotypes recognized globally. Here, we report the whole-genome sequence of S. Typhimurium strain UPM 260, isolated from a broiler chicken.

scholarly journals Association of a Protective Monoclonal IgA with the O Antigen of Salmonella enterica Serovar Typhimurium Impacts Type 3 Secretion and Outer Membrane Integrity

2012 ◽  
Vol 80 (7) ◽  
pp. 2454-2463 ◽  
Author(s):  
Stephen J. Forbes ◽  
Daniel Martinelli ◽  
Chyongere Hsieh ◽  
Jeffrey G. Ault ◽  
Michael Marko ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Epithelial Cells ◽  
Outer Membrane ◽  
Salmonella Enterica ◽  
Membrane Integrity ◽  
Effector Proteins ◽  
Content Type ◽  
O Antigen ◽  
Serovar Typhimurium ◽  
Type 3

ABSTRACTInvasion of intestinal epithelial cells bySalmonella entericaserovar Typhimurium is an energetically demanding process, involving the transfer of effector proteins from invading bacteria into host cells via a specialized organelle known as theSalmonellapathogenicity island 1 (SPI-1) type 3 secretion system (T3SS). By a mechanism that remains poorly understood, entry ofS. Typhimurium into epithelial cells is inhibited by Sal4, a monoclonal, polymeric IgA antibody that binds an immunodominant epitope within the O-antigen (O-Ag) component of lipopolysaccharide. In this study, we investigated how the binding of Sal4 to the surface ofS. Typhimurium influences T3SS activity, bacterial energetics, and outer membrane integrity. We found that Sal4 treatment impaired T3SS-mediated translocon formation and attenuated the delivery of tagged effector proteins into epithelial cells. Sal4 treatment coincided with a partial reduction in membrane energetics and intracellular ATP levels, possibly explaining the impairment in T3SS activity. Sal4's effects on bacterial secretion and energetics occurred concurrently with an increase in O-Ag levels in culture supernatants, alterations in outer membrane permeability, and changes in surface ultrastructure, as revealed by transmission electron microscopy and cryo-electron microscopy. We propose that Sal4, by virtue of its ability to bind and cross-link the O-Ag, induces a form of outer membrane stress that compromises the integrity of theS. Typhimurium cell envelope and temporarily renders the bacterium avirulent.

scholarly journals Draft Genome Sequence of Lactobacillus fermentum Lf2, an Exopolysaccharide-Producing Strain Isolated from Argentine Cheese

2018 ◽  
Vol 7 (18) ◽  
Author(s):  
Hugh M. B. Harris ◽  
Elisa C. Ale ◽  
Jorge A. Reinheimer ◽  
Ana G. Binetti ◽  
Paul W. O’Toole
Keyword(s):  
Genome Sequence ◽  
Salmonella Enterica ◽  
Draft Genome ◽  
Protective Role ◽  
Lactobacillus Fermentum ◽  
Draft Genome Sequence ◽  
Content Type ◽  
Serovar Typhimurium ◽  
High Concentrations

Lactobacillus fermentum Lf2, an Argentine cheese isolate, can produce high concentrations of exopolysaccharides (EPS). These EPS were shown to improve the texture and rheology of yogurt, as well as to play a protective role in mice exposed to Salmonella enterica serovar Typhimurium.

scholarly journals Regulation of RamA by RamR in Salmonella enterica Serovar Typhimurium: Isolation of a RamR Superrepressor

2012 ◽  
Vol 56 (11) ◽  
pp. 6037-6040 ◽  
Author(s):  
Vito Ricci ◽  
Stephen J. W. Busby ◽  
Laura J. V. Piddock
Keyword(s):  
Transcription Factor ◽  
Salmonella Enterica ◽  
Fluorescent Protein ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Promoter Sequence ◽  
Palindromic Sequence ◽  
Content Type ◽  
Gfp Reporter ◽  
Serovar Typhimurium ◽  
Green Fluorescent

ABSTRACTRamA is a transcription factor involved in regulating multidrug resistance inSalmonella entericaserovar Typhimurium SL1344. Green fluorescent protein (GFP) reporter fusions were exploited to investigate the regulation of RamA expression by RamR. We show that RamR represses theramApromoter by binding to a palindromic sequence and describe a superrepressor RamR mutant that binds to theramApromoter sequence more efficiently, thus exhibiting aramAinactivated phenotype.

scholarly journals Curcumin Reduces the Motility of Salmonella enterica Serovar Typhimurium by Binding to the Flagella, Thereby Leading to Flagellar Fragility and Shedding

2016 ◽  
Vol 198 (13) ◽  
pp. 1798-1811 ◽  
Author(s):  
Sandhya Amol Marathe ◽  
Arjun Balakrishnan ◽  
Vidya Devi Negi ◽  
Deepika Sakorey ◽  
Nagasuma Chandra ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Binding Assay ◽  
Protein A ◽  
Intestinal Barrier ◽  
Site Directed Mutagenesis ◽  
Content Type ◽  
Serovar Typhimurium ◽  
Flagellar Filament ◽  
Fluorescence Binding ◽  
Fluorescence Binding Assay

ABSTRACTOne of the important virulence properties of the pathogen is its ability to travel to a favorable environment, cross the viscous mucus barrier (intestinal barrier for enteric pathogens), and reach the epithelia to initiate pathogenesis with the help of an appendage, like flagella. Nonetheless, flagella can act as an “Achilles heel,” revealing the pathogen's presence to the host through the stimulation of innate and adaptive immune responses. We assessed whether curcumin, a dietary polyphenol, could alter the motility ofSalmonella, a foodborne pathogen. It reduced the motility ofSalmonella entericaserovar Typhimurium by shortening the length of the flagellar filament (from ∼8 μm to ∼5 μm) and decreasing its density (4 or 5 flagella/bacterium instead of 8 or 9 flagella/bacterium). Upon curcumin treatment, the percentage of flagellated bacteria declined from ∼84% to 59%. However, no change was detected in the expression of the flagellin gene and protein. A fluorescence binding assay demonstrated binding of curcumin to the flagellar filament. This might make the filament fragile, breaking it into smaller fragments. Computational analysis predicted the binding of curcumin, its analogues, and its degraded products to a flagellin molecule at an interface between domains D1 and D2. Site-directed mutagenesis and a fluorescence binding assay confirmed the binding of curcumin to flagellin at residues ASN120, ASP123, ASN163, SER164, ASN173, and GLN175.IMPORTANCEThis work, to our knowledge the first report of its kind, examines how curcumin targets flagellar density and affects the pathogenesis of bacteria. We found that curcumin does not affect any of the flagellar synthesis genes. Instead, it binds to the flagellum and makes it fragile. It increases the torsional stress on the flagellar filament that then breaks, leaving fewer flagella around the bacteria. Flagella, which are crucial ligands for Toll-like receptor 5, are some of the most important appendages ofSalmonella. Curcumin is an important component of turmeric, which is a major spice used in Asian cooking. The loss of flagella can, in turn, change the pathogenesis of bacteria, making them more robust and fit in the host.

scholarly journals Role of sapA and yfgA in Susceptibility to Antibody-Mediated Complement-Dependent Killing and Virulence of Salmonella enterica Serovar Typhimurium

2017 ◽  
Vol 85 (9) ◽  
Author(s):  
Edna M. Ondari ◽  
Jennifer N. Heath ◽  
Elizabeth J. Klemm ◽  
Gemma Langridge ◽  
Lars Barquist ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Protein Translocation ◽  
Invasive Disease ◽  
Immune Serum ◽  
Insertion Mutant ◽  
Content Type ◽  
Serovar Typhimurium ◽  
Serum Killing ◽  
Increased Sensitivity

ABSTRACT The ST313 pathovar of Salmonella enterica serovar Typhimurium contributes to a high burden of invasive disease among African infants and HIV-infected adults. It is characterized by genome degradation (loss of coding capacity) and has increased resistance to antibody-dependent complement-mediated killing compared with enterocolitis-causing strains of S. Typhimurium. Vaccination is an attractive disease-prevention strategy, and leading candidates focus on the induction of bactericidal antibodies. Antibody-resistant strains arising through further gene deletion could compromise such a strategy. Exposing a saturating transposon insertion mutant library of S. Typhimurium to immune serum identified a repertoire of S. Typhimurium genes that, when interrupted, result in increased resistance to serum killing. These genes included several involved in bacterial envelope biogenesis, protein translocation, and metabolism. We generated defined mutant derivatives using S. Typhimurium SL1344 as the host. Based on their initial levels of enhanced resistance to killing, yfgA and sapA mutants were selected for further characterization. The S. Typhimurium yfgA mutant lost the characteristic Salmonella rod-shaped appearance, exhibited increased sensitivity to osmotic and detergent stress, lacked very long lipopolysaccharide, was unable to invade enterocytes, and demonstrated decreased ability to infect mice. In contrast, the S. Typhimurium sapA mutants had similar sensitivity to osmotic and detergent stress and lipopolysaccharide profile and an increased ability to infect enterocytes compared with the wild type, but it had no increased ability to cause in vivo infection. These findings indicate that increased resistance to antibody-dependent complement-mediated killing secondary to genetic deletion is not necessarily accompanied by increased virulence and suggest the presence of different mechanisms of antibody resistance.

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