Intra-Amniotic Infection with Ureaplasma parvum Causes Preterm Birth and Neonatal Mortality That Are Prevented by Treatment with Clarithromycin

ABSTRACT Intra-amniotic infection is strongly associated with adverse pregnancy and neonatal outcomes. Most intra-amniotic infections are due to Ureaplasma species; however, the pathogenic potency of these genital mycoplasmas to induce preterm birth is still controversial. Here, we first laid out a taxonomic characterization of Ureaplasma isolates from women with intra-amniotic infection, which revealed that Ureaplasma parvum is the most common bacterium found in this clinical condition. Next, using animal models, we provided a causal link between intra-amniotic inoculation with Ureaplasma species and preterm birth. Importantly, the intra-amniotic inoculation of Ureaplasma species induced high rates of mortality in both preterm and term neonates. The in vivo potency of U. parvum to induce preterm birth was not associated with known virulence factors. However, term-derived and preterm-derived U. parvum isolates were capable of inducing an intra-amniotic inflammatory response. Both U. parvum isolates invaded several fetal tissues, primarily the fetal lung, and caused fetal inflammatory response syndrome. This bacterium was also detected in the placenta, reproductive tissues, and most severely in the fetal membranes, inducing a local inflammatory response that was replicated in an in vitro model. Importantly, treatment with clarithromycin, a recently recommended yet not widely utilized antibiotic, prevented the adverse pregnancy and neonatal outcomes induced by U. parvum. These findings shed light on the maternal-fetal immunobiology of intra-amniotic infection. IMPORTANCE Preterm birth is the leading cause of neonatal morbidity and mortality worldwide. Multiple etiologies are associated with preterm birth; however, 25% of preterm infants are born to a mother with intra-amniotic infection, most commonly due to invasion of the amniotic cavity by Ureaplasma species. Much research has focused on establishing a link between Ureaplasma species and adverse pregnancy/neonatal outcomes; however, little is known about the taxonomy of and host response against Ureaplasma species. Here, we applied a multifaceted approach, including human samples, in vivo models, and in vitro manipulations, to study the maternal-fetal immunobiology of Ureaplasma infection during pregnancy. Furthermore, we investigated the use of clarithromycin as a treatment for this infection. Our research provides translational knowledge that bolsters scientific understanding of Ureaplasma species as a cause of adverse pregnancy/neonatal outcomes and gives strong evidence for the use of clarithromycin as the recommended treatment for women intra-amniotically infected with Ureaplasma species.

Download Full-text

Ursodeoxycholic Acid (UDCA) Mitigates the Host Inflammatory Response during Clostridioides difficile Infection by Altering Gut Bile Acids

Infection and Immunity ◽

10.1128/iai.00045-20 ◽

2020 ◽

Vol 88 (6) ◽

Author(s):

Jenessa A. Winston ◽

Alissa J. Rivera ◽

Jingwei Cai ◽

Rajani Thanissery ◽

Stephanie A. Montgomery ◽

...

Keyword(s):

Immune Response ◽

Bile Acid ◽

Inflammatory Response ◽

Innate Immune Response ◽

Innate Immune ◽

Colonization Resistance ◽

Content Type ◽

Clostridioides Difficile

ABSTRACT Clostridioides difficile infection (CDI) is associated with increasing morbidity and mortality posing an urgent threat to public health. Recurrence of CDI after successful treatment with antibiotics is high, thus necessitating discovery of novel therapeutics against this enteric pathogen. Administration of the secondary bile acid ursodeoxycholic acid (UDCA; ursodiol) inhibits the life cycles of various strains of C. difficile in vitro, suggesting that the FDA-approved formulation of UDCA, known as ursodiol, may be able to restore colonization resistance against C. difficile in vivo. However, the mechanism(s) by which ursodiol is able to restore colonization resistance against C. difficile remains unknown. Here, we confirmed that ursodiol inhibits C. difficile R20291 spore germination and outgrowth, growth, and toxin activity in a dose-dependent manner in vitro. In a murine model of CDI, exogenous administration of ursodiol resulted in significant alterations in the bile acid metabolome with little to no changes in gut microbial community structure. Ursodiol pretreatment resulted in attenuation of CDI pathogenesis early in the course of disease, which coincided with alterations in the cecal and colonic inflammatory transcriptome, bile acid-activated receptors nuclear farnesoid X receptor (FXR) and transmembrane G-protein-coupled membrane receptor 5 (TGR5), which are able to modulate the innate immune response through signaling pathways such as NF-κB. Although ursodiol pretreatment did not result in a consistent decrease in the C. difficile life cycle in vivo, it was able to attenuate an overly robust inflammatory response that is detrimental to the host during CDI. Ursodiol remains a viable nonantibiotic treatment and/or prevention strategy against CDI. Likewise, modulation of the host innate immune response via bile acid-activated receptors FXR and TGR5 represents a new potential treatment strategy for patients with CDI.

Download Full-text

Filamentous Bacteriophage Produced by Pseudomonas aeruginosa Alters the Inflammatory Response and Promotes Noninvasive Infection In Vivo

Infection and Immunity ◽

10.1128/iai.00648-16 ◽

2016 ◽

Vol 85 (1) ◽

Cited By ~ 36

Author(s):

Patrick R. Secor ◽

Lia A. Michaels ◽

Kate S. Smigiel ◽

Maryam G. Rohani ◽

Laura K. Jennings ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Inflammatory Response ◽

Chronic Infection ◽

Bacterial Invasion ◽

Airway Epithelial ◽

Content Type ◽

Epithelial Cultures ◽

Opportunistic Human Pathogen

ABSTRACT Pseudomonas aeruginosa is an important opportunistic human pathogen that lives in biofilm-like cell aggregates at sites of chronic infection, such as those that occur in the lungs of patients with cystic fibrosis and nonhealing ulcers. During growth in a biofilm, P. aeruginosa dramatically increases the production of filamentous Pf bacteriophage (Pf phage). Previous work indicated that when in vivo Pf phage production was inhibited, P. aeruginosa was less virulent. However, it is not clear how the production of abundant quantities of Pf phage similar to those produced by biofilms under in vitro conditions affects pathogenesis. Here, using a murine pneumonia model, we show that the production of biofilm-relevant amounts of Pf phage prevents the dissemination of P. aeruginosa from the lung. Furthermore, filamentous phage promoted bacterial adhesion to mucin and inhibited bacterial invasion of airway epithelial cultures, suggesting that Pf phage traps P. aeruginosa within the lung. The in vivo production of Pf phage was also associated with reduced lung injury, reduced neutrophil recruitment, and lower cytokine levels. Additionally, when producing Pf phage, P. aeruginosa was less prone to phagocytosis by macrophages than bacteria not producing Pf phage. Collectively, these data suggest that filamentous Pf phage alters the progression of the inflammatory response and promotes phenotypes typically associated with chronic infection.

Download Full-text

Dectin Immunoadhesins and Pneumocystis Pneumonia

Infection and Immunity ◽

10.1128/iai.00136-13 ◽

2013 ◽

Vol 81 (9) ◽

pp. 3451-3462 ◽

Cited By ~ 19

Author(s):

David M. Ricks ◽

Kong Chen ◽

Mingquan Zheng ◽

Chad Steele ◽

Jay K. Kolls

Keyword(s):

Inflammatory Response ◽

Opportunistic Pathogen ◽

Pneumocystis Pneumonia ◽

Carbohydrate Binding ◽

Content Type ◽

Specificity Of Binding ◽

Inflammatory Syndrome ◽

Dependent Mechanism

ABSTRACTThe opportunistic pathogenPneumocystis jiroveciiis a significant cause of disease in HIV-infected patients and others with immunosuppressive conditions.Pneumocystiscan also cause complications in treatment following antiretroviral therapy or reversal of immunosuppressive therapy, as the newly reconstituted immune system can develop a pathological inflammatory response to remaining antigens or a previously undetected infection. To target β-(1,3)-glucan, a structural component of thePneumocystiscell wall with immune-stimulating properties, we have developed immunoadhesins consisting of the carbohydrate binding domain of Dectin-1 fused to the Fc regions of the 4 subtypes of murine IgG (mIgG). These immunoadhesins bind β-glucan with high affinity, and precoating the surface of zymosan with Dectin-1:Fc can reduce cytokine production by macrophages in anin vitrostimulation assay. All Dectin-1:Fc variants showed specificity of binding to the asci ofPneumocystis murina, but effector activity of the fusion molecules varied depending on Fc subtype. Dectin-1:mIgG2a Fc was able to reduce the viability ofP. murinain culture through a complement-dependent mechanism, whereas previous studies have shown the mIgG1 Fc fusion to increase macrophage-dependent killing. In anin vivochallenge model, systemic expression of Dectin-1:mIgG1 Fc significantly reduced ascus burden in the lung. When administered postinfection in a model of immune reconstitution inflammatory syndrome (IRIS), both Dectin-1:mIgG1 and Dectin-1:mIgG2a Fc reduced hypoxemia despite minimal effects on fungal burden in the lung. Taken together, these data indicate that molecules targeting β-glucan may provide a mechanism for treatment of fungal infection and for modulation of the inflammatory response toPneumocystisand other pathogens.

Download Full-text

Pulsed Electromagnetic Field Stimulation in Osteogenesis and Chondrogenesis: Signaling Pathways and Therapeutic Implications

International Journal of Molecular Sciences ◽

10.3390/ijms22020809 ◽

2021 ◽

Vol 22 (2) ◽

pp. 809

Author(s):

Katia Varani ◽

Fabrizio Vincenzi ◽

Silvia Pasquini ◽

Irene Blo ◽

Simona Salati ◽

...

Keyword(s):

Inflammatory Response ◽

Signaling Pathways ◽

Tissue Repair ◽

Chondrogenic Differentiation ◽

Cartilage Defects ◽

Invasive Treatment ◽

Local Inflammatory Response ◽

Pulsed Electromagnetic

Mesenchymal stem cells (MSCs) are the main cell players in tissue repair and thanks to their self-renewal and multi-lineage differentiation capabilities, they gained significant attention as cell source for tissue engineering (TE) approaches aimed at restoring bone and cartilage defects. Despite significant progress, their therapeutic application remains debated: the TE construct often fails to completely restore the biomechanical properties of the native tissue, leading to poor clinical outcomes in the long term. Pulsed electromagnetic fields (PEMFs) are currently used as a safe and non-invasive treatment to enhance bone healing and to provide joint protection. PEMFs enhance both osteogenic and chondrogenic differentiation of MSCs. Here, we provide extensive review of the signaling pathways modulated by PEMFs during MSCs osteogenic and chondrogenic differentiation. Particular attention has been given to the PEMF-mediated activation of the adenosine signaling and their regulation of the inflammatory response as key player in TE approaches. Overall, the application of PEMFs in tissue repair is foreseen: (1) in vitro: to improve the functional and mechanical properties of the engineered construct; (2) in vivo: (i) to favor graft integration, (ii) to control the local inflammatory response, and (iii) to foster tissue repair from both implanted and resident MSCs cells.

Download Full-text

Arabinoxylans from rice bran and wheat immunomodulatory potentials: a review article

Nutrition & Food Science ◽

10.1108/nfs-06-2017-0111 ◽

2018 ◽

Vol 48 (1) ◽

pp. 97-110 ◽

Cited By ~ 2

Author(s):

Abdulmannan Fadel ◽

Andrew Plunkett ◽

Weili Li ◽

Yazan Ranneh ◽

Vivian Elewosi Tessu Gyamfi ◽

...

Keyword(s):

Molecular Weight ◽

Immune Response ◽

Inflammatory Response ◽

Rice Bran ◽

Mechanism Of Action ◽

Content Type ◽

Method Of Extraction

Purpose The purpose of this study is to discuss recent research on arabinoxylans from rice bran and wheat byproducts and their immunomodulatory potentials. Also, a potential receptor for arabinoxylans is proposed in relation to arabinoxylans structure. Design/methodology/approach This review summarises recent publications on arabinoxylans from rice bran and wheat, classification of arabinoxylans, a brief background on their method of extraction and their immunomodulatory potentials as they induce pro-inflammatory response in vitro, in vivo and in humans. The mechanism of action in which arabinoxylans modulate the immune activity is yet to be discovered, However, the authors have proposed a potential receptor for arabinoxylans in relation to arabinoxylans structure and molecular weight. Findings The effects of arabinoxylans from rice bran and wheat on the immune response was found to cause a pro-inflammatory response in vitro, in vivo and in humans. Also, the immune response depends on arabinoxylans structure, the degree of branching and origin. Originality/value This review paper focuses on the effects of arabinoxylans from rice bran and wheat on immunomodulatory potentials in vitro, in vivo and in humans. A new mechanism of action has been proposed based on the literature and via linking between arabinoxylans and lipopolysaccharide structure, molecular weight and suggested proposed receptor, which might be activated via both of them.

Download Full-text

Inhibitory effects of epimedium herb water extract on the inflammatory response in vitro and in vivo

Planta Medica ◽

10.1055/s-0036-1596615 ◽

2016 ◽

Vol 81 (S 01) ◽

pp. S1-S381

Author(s):

YC Oh ◽

YH Jeong ◽

WK Cho ◽

SJ Lee ◽

JY Ma

Keyword(s):

Inflammatory Response ◽

Water Extract ◽

Inhibitory Effects

Download Full-text

Repurposing N,N-Dimethylacetamide (DMA), a Pharmaceutical Excipient, as a Prototype Novel Anti-inflammatory Agent for the Prevention and/or Treatment of Preterm Birth

Current Pharmaceutical Design ◽

10.2174/1381612824666180130121706 ◽

2018 ◽

Vol 24 (9) ◽

pp. 989-992 ◽

Cited By ~ 4

Author(s):

Samir Gorasiya ◽

Juliet Mushi ◽

Ryan Pekson ◽

Sabesan Yoganathan ◽

Sandra E. Reznik

Keyword(s):

Preterm Birth ◽

Ex Vivo ◽

The United States ◽

Occurrence Rate ◽

Pharmaceutical Excipient ◽

Ongoing Work ◽

Exciting Line ◽

Pregnant Mice

Background: Preterm birth (PTB), or birth that occurs before 37 weeks of gestation, accounts for the majority of perinatal morbidity and mortality. As of 2016, PTB has an occurrence rate of 9.6% in the United States and accounts for up to 18 percent of births worldwide. Inflammation has been identified as the most common cause of PTB, but effective pharmacotherapy has yet to be developed to prevent inflammation driven PTB. Our group has discovered that N,N-dimethylacetamide (DMA), a readily available solvent commonly used as a pharmaceutical excipient, rescues lipopolysaccharide (LPS)-induced timed pregnant mice from PTB. Methods: We have used in vivo, ex vivo and in vitro approaches to investigate this compound further. Results: Interestingly, we found that DMA suppresses cytokine secretion by inhibiting nuclear factor-kappa B (NF-κB). In ongoing work in this exciting line of investigation, we are currently investigating structural analogs of DMA, some of them novel, to optimize this approach focused on the inflammation associated with PTB. Conclusion: Successful development of pharmacotherapy for the prevention of PTB rests upon the pursuit of multiple strategies to solve this important clinical challenge.

Download Full-text

Imidazolidinyl urea activates mast cells via MRGPRX2 to induce non-histaminergic allergy

Toxicology Research ◽

10.1093/toxres/tfab035 ◽

2021 ◽

Author(s):

Jiapan Gao ◽

Delu Che ◽

Xueshan Du ◽

Yi Zheng ◽

Huiling Jing ◽

...

Keyword(s):

Contact Dermatitis ◽

Mast Cells ◽

Pharmaceutical Products ◽

Drug Induced ◽

Inflammatory Infiltration ◽

Local Inflammatory Response ◽

Allergic Contact ◽

G Protein Coupled

Abstract Imidazolidinyl urea (IU) is used as an antimicrobial preservative in cosmetic and pharmaceutical products. IU induces allergic contact dermatitis, however, the mechanism has not yet been elucidated. Mas-related G protein-coupled receptor-X2 (MRGPRX2) triggers drug-induced pseudo-allergic reactions. The aims of this study were to determine whether IU activated mast cells through MRGPRX2 to further trigger contact dermatitis. Wild-type (WT) and KitW-sh/HNihrJaeBsmJNju (MUT) mice were treated with IU to observe its effects on local inflammation and mast cells degranulation in vivo. Laboratory of allergic disease 2 cells were used to detect calcium mobilization and release of inflammatory mediators in vitro. WT mice showed a severe local inflammatory response and contact dermatitis, whereas only slight inflammatory infiltration was observed in MUT mice. Thus, MRGPRX2 mediated the IU-induced activation of mast cells. However, histamine, a typical allergen, was not involved in this process. Tryptase expressed by mast cells was the major non-histaminergic inflammatory mediator of contact dermatitis. IU induced anaphylactic reaction via MRGPRX2 and further triggering non-histaminergic contact dermatitis, which explained why antihistamines are clinically ineffective against some chronic dermatitis.

Download Full-text

Exogenous Alginate Protects Staphylococcus aureus from Killing by Pseudomonas aeruginosa

Journal of Bacteriology ◽

10.1128/jb.00559-19 ◽

2019 ◽

Vol 202 (8) ◽

Cited By ~ 2

Author(s):

Courtney E. Price ◽

Dustin G. Brown ◽

Dominique H. Limoli ◽

Vanessa V. Phelan ◽

George A. O’Toole

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Physical Space ◽

Late Time ◽

Protective Effects ◽

Content Type ◽

Alginate Production ◽

The Impact

ABSTRACT Cystic fibrosis (CF) patients chronically infected with both Pseudomonas aeruginosa and Staphylococcus aureus have worse health outcomes than patients who are monoinfected with either P. aeruginosa or S. aureus. We showed previously that mucoid strains of P. aeruginosa can coexist with S. aureus in vitro due to the transcriptional downregulation of several toxic exoproducts typically produced by P. aeruginosa, including siderophores, rhamnolipids, and HQNO (2-heptyl-4-hydroxyquinoline N-oxide). Here, we demonstrate that exogenous alginate protects S. aureus from P. aeruginosa in both planktonic and biofilm coculture models under a variety of nutritional conditions. S. aureus protection in the presence of exogenous alginate is due to the transcriptional downregulation of pvdA, a gene required for the production of the iron-scavenging siderophore pyoverdine as well as the downregulation of the PQS (Pseudomonas quinolone signal) (2-heptyl-3,4-dihydroxyquinoline) quorum sensing system. The impact of exogenous alginate is independent of endogenous alginate production. We further demonstrate that coculture of mucoid P. aeruginosa with nonmucoid P. aeruginosa strains can mitigate the killing of S. aureus by the nonmucoid strain of P. aeruginosa, indicating that the mechanism that we describe here may function in vivo in the context of mixed infections. Finally, we investigated a panel of mucoid clinical isolates that retain the ability to kill S. aureus at late time points and show that each strain has a unique expression profile, indicating that mucoid isolates can overcome the S. aureus-protective effects of mucoidy in a strain-specific manner. IMPORTANCE CF patients are chronically infected by polymicrobial communities. The two dominant bacterial pathogens that infect the lungs of CF patients are P. aeruginosa and S. aureus, with ∼30% of patients coinfected by both species. Such coinfected individuals have worse outcomes than monoinfected patients, and both species persist within the same physical space. A variety of host and environmental factors have been demonstrated to promote P. aeruginosa-S. aureus coexistence, despite evidence that P. aeruginosa kills S. aureus when these organisms are cocultured in vitro. Thus, a better understanding of P. aeruginosa-S. aureus interactions, particularly mechanisms by which these microorganisms are able to coexist in proximal physical space, will lead to better-informed treatments for chronic polymicrobial infections.

Download Full-text

In Vitro Synergy and In Vivo Activity of Tigecycline-Ciprofloxacin Combination Therapy against Vibrio vulnificus Sepsis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00310-19 ◽

2019 ◽

Vol 63 (10) ◽

Author(s):

Seong Eun Kim ◽

Hee Kyung Kim ◽

Su-Mi Choi ◽

Yohan Yu ◽

Uh Jin Kim ◽

...

Keyword(s):

Survival Rate ◽

Mortality Rate ◽

Combination Therapy ◽

Combination Treatment ◽

Vibrio Vulnificus ◽

Antibiotic Regimen ◽

Content Type ◽

Time Kill

ABSTRACT The mortality rate associated with Vibrio vulnificus sepsis remains high. An in vitro time-kill assay revealed synergism between tigecycline and ciprofloxacin. The survival rate was significantly higher in mice treated with tigecycline plus ciprofloxacin than in mice treated with cefotaxime plus minocycline. Thus, combination treatment with tigecycline-ciprofloxacin may be an effective novel antibiotic regimen for V. vulnificus sepsis.

Download Full-text