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1.
Nurs Womens Health ; 2024 May 18.
Article in English | MEDLINE | ID: mdl-38768647

ABSTRACT

OBJECTIVE: To improve knowledge and competency in providing gender-affirming patient care among newly licensed registered nurses (RNs) working in sexual and reproductive health (SRH). DESIGN: Pilot, pretest/posttest, descriptive design. SETTING AND PARTICIPANTS: Participating RNs were employed at a large academic health center in the southeastern United States. All RNs were providing SRH nursing and participating in the health center's new nurse residency program. METHODS AND INTERVENTION: Participants completed an online synchronous training that introduced topics such as sex versus gender, gender dysphoria, and health disparities. This education was followed by in-person training, where an unfolding case study applied concepts to theoretical patient scenarios specific to reproductive health. Participants completed a 20-item survey with a single assessment retrospective pre-post design to measure change in knowledge and competency. RESULTS: Twelve RNs participated in this pilot study. Fewer than half had previously received instruction on providing care to trans∗ persons. Seven self-perceived knowledge and competency areas were evaluated with paired retrospective pre-post design questions. All areas measured showed increases from pretraining to posttraining. Participants also had the opportunity to respond to open-ended questions. Common themes identified in these responses include participants planning to maintain a greater awareness and intentionality with language and abandoning cisgender assumptions. Several participants also described health care-specific systemic barriers that could prevent a trans∗ patient from feeling comfortable. CONCLUSION: Providing new graduate nurses with education specific to trans∗ patients may help them to feel more knowledgeable and competent when caring for these individuals in SRH settings.

2.
mBio ; 14(3): e0051023, 2023 06 27.
Article in English | MEDLINE | ID: mdl-37052506

ABSTRACT

Microbial components have a range of direct effects on the fetal brain. However, little is known about the cellular targets and molecular mechanisms that mediate these effects. Neural progenitor cells (NPCs) control the size and architecture of the brain and understanding the mechanisms regulating NPCs is crucial to understanding brain developmental disorders. We identify ventricular radial glia (vRG), the primary NPC, as the target of bacterial cell wall (BCW) generated during the antibiotic treatment of maternal pneumonia. BCW enhanced proliferative potential of vRGs by shortening the cell cycle and increasing self-renewal. Expanded vRGs propagated to increase neuronal output in all cortical layers. Remarkably, Toll-like receptor 2 (TLR2), which recognizes BCW, localized at the base of primary cilia in vRGs and the BCW-TLR2 interaction suppressed ciliogenesis leading to derepression of Hedgehog (HH) signaling and expansion of vRGs. We also show that TLR6 is an essential partner of TLR2 in this process. Surprisingly, TLR6 alone was required to set the number of cortical neurons under healthy conditions. These findings suggest that an endogenous signal from TLRs suppresses cortical expansion during normal development of the neocortex and that BCW antagonizes that signal through the TLR2/cilia/HH signaling axis changing brain structure and function. IMPORTANCE Fetal brain development in early gestation can be impacted by transplacental infection, altered metabolites from the maternal microbiome, or maternal immune activation. It is less well understood how maternal microbial subcomponents that cross the placenta, such as bacterial cell wall (BCW), directly interact with fetal neural progenitors and neurons and affect development. This scenario plays out in the clinic when BCW debris released during antibiotic therapy of maternal infection traffics to the fetal brain. This study identifies the direct interaction of BCW with TLR2/6 present on the primary cilium, the signaling hub on fetal neural progenitor cells (NPCs). NPCs control the size and architecture of the brain and understanding the mechanisms regulating NPCs is crucial to understanding brain developmental disorders. Within a window of vulnerability before the appearance of fetal immune cells, the BCW-TLR2/6 interaction results in the inhibition of ciliogenesis, derepression of Sonic Hedgehog signaling, excess proliferation of neural progenitors, and abnormal cortical architecture. In the first example of TLR signaling linked to Sonic Hedgehog, BCW/TLR2/6 appears to act during fetal brain morphogenesis to play a role in setting the total cell number in the neocortex.


Subject(s)
Hedgehog Proteins , Neocortex , Pregnancy , Female , Humans , Hedgehog Proteins/metabolism , Neocortex/metabolism , Toll-Like Receptor 2/metabolism , Ligands , Toll-Like Receptor 6/metabolism
3.
Vaccines (Basel) ; 9(3)2021 Mar 02.
Article in English | MEDLINE | ID: mdl-33801372

ABSTRACT

Streptococcus pneumoniae (Spn) is a bacterial pathogen known to colonize the upper respiratory tract and cause serious opportunistic diseases such as pneumonia, bacteremia, sepsis and meningitis. As a consequence, millions of attributable deaths occur annually, especially among infants, the elderly and immunocompromised individuals. Although current vaccines, composed of purified pneumococcal polysaccharide in free form or conjugated to a protein carrier, are widely used and have been demonstrated to be effective in target groups, Spn has continued to colonize and cause life-threatening disease in susceptible populations. This lack of broad protection highlights the necessity of improving upon the current "gold standard" pneumococcal vaccines to increase protection both by decreasing colonization and reducing the incidence of sterile-site infections. Over the past century, most of the pneumococcal proteins that play an essential role in colonization and pathogenesis have been identified and characterized. Some of these proteins have the potential to serve as antigens in a multi-valent protein vaccine that confers capsule independent protection. This review seeks to summarize the benefits and limitations of the currently employed vaccine strategies, describes how leading candidate proteins contribute to pneumococcal disease development, and discusses the potential of these proteins as protective antigens-including as a hybrid construct.

4.
Pathogens ; 8(4)2019 Oct 23.
Article in English | MEDLINE | ID: mdl-31652741

ABSTRACT

Pneumococcal vaccine development is driven by the achievement of high activity in a single gatekeeper assay: the bacterial opsonophagocytic killing (OPK) assay. New evidence challenges the dogma that anti-capsular antibodies have only a single function that predicts success. The emerging concept of multi-modal protection presents an array of questions that are fundamental to adopting a new vaccine design process. If antibodies have hidden non-opsonic functions that are protective, should these be optimized for better vaccines? What would protein antigens add to protective activity? Are cellular immune functions additive to antibodies for success? Do different organs benefit from different modes of protection? Can vaccine activities beyond OPK protect the immunocompromised host? This commentary raises these issues at a time when capsule-only OPK assay-based vaccines are increasingly seen as a limiting strategy.

5.
Infect Immun ; 87(10)2019 10.
Article in English | MEDLINE | ID: mdl-31308088

ABSTRACT

Acute otitis media is one of the most common childhood infections worldwide. Currently licensed vaccines against the common otopathogen Streptococcus pneumoniae target the bacterial capsular polysaccharide and confer no protection against nonencapsulated strains or capsular types outside vaccine coverage. Mucosal infections such as acute otitis media remain prevalent, even those caused by vaccine-covered serotypes. Here, we report that a protein-based vaccine, a fusion construct of epitopes of CbpA to pneumolysin toxoid, confers effective protection against pneumococcal acute otitis media for non-PCV-13 serotypes and enhances protection for PCV-13 serotypes when coadministered with PCV-13. Having cross-reactive epitopes, the fusion protein also induces potent antibody responses against nontypeable Haemophilus influenzae and S. pneumoniae, engendering protection against acute otitis media caused by emerging unencapsulated otopathogens. These data suggest that augmenting capsule-based vaccination with conserved, cross-reactive protein-based vaccines broadens and enhances protection against acute otitis media.


Subject(s)
Antibodies, Bacterial/biosynthesis , Haemophilus Infections/prevention & control , Haemophilus influenzae/immunology , Otitis Media/prevention & control , Pneumococcal Vaccines/biosynthesis , Recombinant Fusion Proteins/biosynthesis , Streptococcus pneumoniae/immunology , Acute Disease , Animals , Bacterial Proteins/biosynthesis , Bacterial Proteins/genetics , Cross Protection , Cross Reactions , Female , Gene Expression , Haemophilus Infections/immunology , Haemophilus Infections/microbiology , Haemophilus influenzae/drug effects , Haemophilus influenzae/pathogenicity , Humans , Immunogenicity, Vaccine , Mice , Mice, Inbred BALB C , Otitis Media/immunology , Otitis Media/microbiology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/genetics , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/genetics , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/pathogenicity , Streptolysins/biosynthesis , Streptolysins/genetics , Toxoids/biosynthesis , Toxoids/genetics , Vaccination , Vaccines, Synthetic
6.
mBio ; 8(5)2017 09 19.
Article in English | MEDLINE | ID: mdl-28928207

ABSTRACT

Obesity is a risk factor for developing severe disease following influenza virus infection; however, the comorbidity of obesity and secondary bacterial infection, a serious complication of influenza virus infections, is unknown. To fill this gap in knowledge, lean and obese C57BL/6 mice were infected with a nonlethal dose of influenza virus followed by a nonlethal dose of Streptococcus pneumoniae Strikingly, not only did significantly enhanced death occur in obese coinfected mice compared to lean controls, but also high mortality was seen irrespective of influenza virus strain, bacterial strain, or timing of coinfection. This result was unexpected, given that most influenza virus strains, especially seasonal human A and B viruses, are nonlethal in this model. Both viral and bacterial titers were increased in the upper respiratory tract and lungs of obese animals as early as days 1 and 2 post-bacterial infection, leading to a significant decrease in lung function. This increased bacterial load correlated with extensive cellular damage and upregulation of platelet-activating factor receptor, a host receptor central to pneumococcal invasion. Importantly, while vaccination of obese mice against either influenza virus or pneumococcus failed to confer protection, antibiotic treatment was able to resolve secondary bacterial infection-associated mortality. Overall, secondary bacterial pneumonia could be a widespread, unaddressed public health problem in an increasingly obese population.IMPORTANCE Worldwide obesity rates have continued to increase. Obesity is associated with increased severity of influenza virus infection; however, very little is known about respiratory coinfections in this expanding, high-risk population. Our studies utilized a coinfection model to show that obesity increases mortality from secondary bacterial infection following influenza virus challenge through a "perfect storm" of host factors that lead to excessive viral and bacterial outgrowth. In addition, we found that vaccination of obese mice against either virus or bacteria failed to confer protection against coinfection, but antibiotic treatment did alleviate mortality. Combined, these results represent an understudied and imminent public health concern in a weighty portion of the global population.


Subject(s)
Coinfection/etiology , Influenza A virus/isolation & purification , Influenza Vaccines/administration & dosage , Obesity/complications , Orthomyxoviridae Infections/complications , Pneumococcal Vaccines/administration & dosage , Animals , Coinfection/microbiology , Coinfection/virology , Comorbidity , Influenza A virus/growth & development , Lung/microbiology , Lung/virology , Mice , Mice, Inbred C57BL , Mice, Obese , Obesity/microbiology , Obesity/virology , Orthomyxoviridae Infections/microbiology , Orthomyxoviridae Infections/prevention & control , Orthomyxoviridae Infections/virology , Pneumococcal Infections/microbiology , Pneumococcal Infections/prevention & control , Pneumococcal Infections/virology , Treatment Failure , Vaccination
7.
Microbiology (Reading) ; 163(8): 1198-1207, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28749326

ABSTRACT

Neuraminidase A (NanA) is an important virulence factor that is anchored to the pneumococcal cell wall and cleaves sialic acid on host substrates. We noted that a secreted allele of NanA was over-represented in invasive pneumococcal isolates and promoted the development of meningitis when swapped into the genome of non-meningitis isolates replacing cell wall-anchored NanA. Both forms of recombinant NanA directly activated transforming growth factor (TGF)-ß, increased SMAD signalling and promoted loss of endothelial tight junction ZO-1. However, in assays using whole bacteria, only the cell-bound NanA decreased expression of ZO-1 and showed NanA dependence of bacterial invasion of endothelial cells. We conclude that NanA secretion versus retention on the cell surface does not influence neurotropism of clinical isolates. However, we describe a new NanA-TGF-ß signalling axis that leads to decreased blood-brain barrier integrity and enhances bacterial invasion.

9.
Cell Host Microbe ; 19(3): 388-99, 2016 03 09.
Article in English | MEDLINE | ID: mdl-26962947

ABSTRACT

Maternal infection during pregnancy is associated with adverse outcomes for the fetus, including postnatal cognitive disorders. However, the underlying mechanisms are obscure. We find that bacterial cell wall peptidoglycan (CW), a universal PAMP for TLR2, traverses the murine placenta into the developing fetal brain. In contrast to adults, CW-exposed fetal brains did not show any signs of inflammation or neuronal death. Instead, the neuronal transcription factor FoxG1 was induced, and neuroproliferation leading to a 50% greater density of neurons in the cortical plate was observed. Bacterial infection of pregnant dams, followed by antibiotic treatment, which releases CW, yielded the same result. Neuroproliferation required TLR2 and was recapitulated in vitro with fetal neuronal precursor cells and TLR2/6, but not TLR2/1, ligands. The fetal neuroproliferative response correlated with abnormal cognitive behavior in CW-exposed pups following birth. Thus, the bacterial CW-TLR2 signaling axis affects fetal neurodevelopment and may underlie postnatal cognitive disorders.


Subject(s)
Bacterial Infections/complications , Brain/pathology , Cell Proliferation/drug effects , Cognition Disorders/physiopathology , Maternal-Fetal Exchange , Neurons/drug effects , Peptidoglycan/metabolism , Animals , Behavior, Animal , Brain/drug effects , Cognition Disorders/chemically induced , Female , Mice , Neurons/physiology , Pregnancy , Toll-Like Receptor 2/metabolism
10.
Nat Commun ; 7: 10859, 2016 Feb 29.
Article in English | MEDLINE | ID: mdl-26924467

ABSTRACT

Bacterial pathogens produce complex carbohydrate capsules to protect against bactericidal immune molecules. Paradoxically, the pneumococcal capsule sensitizes the bacterium to antimicrobial peptides found on epithelial surfaces. Here we show that upon interaction with antimicrobial peptides, encapsulated pneumococci survive by removing capsule from the cell surface within minutes in a process dependent on the suicidal amidase autolysin LytA. In contrast to classical bacterial autolysis, during capsule shedding, LytA promotes bacterial survival and is dispersed circumferentially around the cell. However, both autolysis and capsule shedding depend on the cell wall hydrolytic activity of LytA. Capsule shedding drastically increases invasion of epithelial cells and is the main pathway by which pneumococci reduce surface bound capsule during early acute lung infection of mice. The previously unrecognized role of LytA in removing capsule to combat antimicrobial peptides may explain why nearly all clinical isolates of pneumococci conserve this enzyme despite the lethal selective pressure of antibiotics.


Subject(s)
Bacterial Capsules/physiology , Epithelial Cells/physiology , Gene Expression Regulation, Enzymologic/physiology , N-Acetylmuramoyl-L-alanine Amidase/metabolism , Streptococcus pneumoniae/metabolism , Animals , Bacterial Adhesion/physiology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Female , Gene Expression Regulation, Bacterial/physiology , Mice , Mutation , N-Acetylmuramoyl-L-alanine Amidase/genetics , Pneumococcal Infections/microbiology , Pneumonia, Pneumococcal/microbiology , Pneumonia, Pneumococcal/pathology
11.
PLoS One ; 11(1): e0146785, 2016.
Article in English | MEDLINE | ID: mdl-26752283

ABSTRACT

Across bacterial species, metal binding proteins can serve functions in pathogenesis in addition to regulating metal homeostasis. We have compared and contrasted the activities of zinc (Zn2+)-binding lipoproteins AdcA and AdcAII in the Streptococcus pneumoniae TIGR4 background. Exposure to Zn2+-limiting conditions resulted in delayed growth in a strain lacking AdcAII (ΔAdcAII) when compared to wild type bacteria or a mutant lacking AdcA (ΔAdcA). AdcAII failed to interact with the extracellular matrix protein laminin despite homology to laminin-binding proteins of related streptococci. Deletion of AdcA or AdcAII led to significantly increased invasion of A549 human lung epithelial cells and a trend toward increased invasion in vivo. Loss of AdcAII, but not AdcA, was shown to negatively impact early colonization of the nasopharynx. Our findings suggest that expression of AdcAII affects invasiveness of S. pneumoniae in response to available Zn2+ concentrations.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Bacterial Proteins/metabolism , Cation Transport Proteins/metabolism , Nasopharynx/microbiology , Pneumococcal Infections/microbiology , Streptococcus pneumoniae/metabolism , Streptococcus pneumoniae/pathogenicity , Zinc/chemistry , ATP-Binding Cassette Transporters/genetics , Animals , Bacterial Proteins/genetics , Cation Transport Proteins/genetics , Cell Adhesion , Cell Line, Tumor , Extracellular Matrix/metabolism , Female , Gene Expression Regulation, Bacterial , Humans , Laminin/metabolism , Mice , Mice, Inbred C57BL , Mutagenesis , Mutation , Oligonucleotide Array Sequence Analysis , Protein Binding
12.
Bio Protoc ; 6(23)2016 Dec 05.
Article in English | MEDLINE | ID: mdl-28573167

ABSTRACT

Cell wall is a complex biopolymer on the surface of all Gram-positive bacteria. During infection, cell wall is recognized by the innate immune receptor Toll-like receptor 2 causing intense inflammation and tissue damage. In animal models, cell wall traffics from the blood stream to many organs in the body, including brain, heart, placenta and fetus. This protocol describes how to prepare purified cell wall from Streptococcus pneumoniae, detect its distribution in animal tissues, and study the tissue response using the placenta and fetal brain as examples.

13.
Clin Vaccine Immunol ; 22(10): 1079-89, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26245351

ABSTRACT

Immunization with the pneumococcal proteins pneumolysin (Ply), choline binding protein A (CbpA), or pneumococcal surface protein A (PspA) elicits protective responses against invasive pneumococcal disease in animal models. In this study, we used different mouse models to test the efficacy of a variety of multivalent protein-based vaccines that comprised various combinations of full-length or peptide regions of the immunogens Ply, CbpA, or PspA: Ply toxoid with the L460D substitution (referred to herein as L460D); L460D fused with protective peptide epitopes from CbpA (YPT-L460D-NEEK [YLN]); L460D fused with the CD2 peptide containing the proline-rich region (PRR) of PspA (CD2-L460D); a combination of L460D and H70 (L460D+H70), a slightly larger PspA-derived peptide containing the PRR and the SM1 region; H70+YLN; and other combinations. Each mouse was immunized either intraperitoneally (i.p.) or subcutaneously (s.c.) with three doses (at 2-week intervals) of the various antigen combinations in alum adjuvant and then challenged in mouse models featuring different infection routes with multiple Streptococcus pneumoniae strains. In the i.p. infection sepsis model, H70+YLN consistently provided significant protection against three different challenge strains (serotypes 1, 2, and 6A); the CD2+YLN and H70+L460D combinations also elicited significant protection. Protection against intravenous (i.v.) sepsis (type 3 and 6A challenge strains) was largely dependent on PspA-derived antigen components, and the most protection was elicited by H70 with or without L460D or YLN. In a type 4 intratracheal (i.t.) challenge model that results in progression to meningitis, antigen combinations that contained YLN elicited the strongest protection. Thus, the trivalent antigen combination of H70+YLN elicited the strongest and broadest protection in diverse pneumococcal challenge models.


Subject(s)
Bacterial Proteins/immunology , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/immunology , Sepsis/prevention & control , Streptococcus pneumoniae/immunology , Streptolysins/immunology , Animals , Bacterial Proteins/genetics , Disease Models, Animal , Epitopes/genetics , Epitopes/immunology , Immunization Schedule , Immunoglobulin G/blood , Meningitis, Pneumococcal/immunology , Meningitis, Pneumococcal/microbiology , Meningitis, Pneumococcal/prevention & control , Mice, Inbred BALB C , Pneumococcal Infections/immunology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/genetics , Pneumonia, Pneumococcal/immunology , Pneumonia, Pneumococcal/microbiology , Pneumonia, Pneumococcal/prevention & control , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Sepsis/microbiology , Streptococcus pneumoniae/classification , Toxoids/immunology , Vaccination , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology
14.
Infect Immun ; 83(4): 1684-94, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25667262

ABSTRACT

In bacteria, the intracellular levels of metals are mediated by tightly controlled acquisition and efflux systems. This is particularly true of copper, a trace element that is universally toxic in excess. During infection, the toxic properties of copper are exploited by the mammalian host to facilitate bacterial clearance. To better understand the role of copper during infection, we characterized the contribution of the cop operon to copper homeostasis and virulence in Streptococcus pneumoniae. Deletion of either the exporter, encoded by copA, or the chaperone, encoded by cupA, led to hypersensitivity to copper stress. We further demonstrated that loss of the copper exporter encoded by copA led to decreased virulence in pulmonary, intraperitoneal, and intravenous models of infection. Deletion of copA resulted in enhanced macrophage-mediated bacterial clearance in vitro. The attenuation phenotype of the copA mutant in the lung was found to be dependent on pulmonary macrophages, underscoring the importance of copper efflux in evading immune defenses. Overall, these data provide insight into the role of the cop operon in pneumococcal pathogenesis.


Subject(s)
Bacterial Proteins/genetics , Cation Transport Proteins/genetics , Copper/metabolism , Pneumococcal Infections/pathology , Streptococcus pneumoniae/pathogenicity , Animals , Bacteremia/genetics , Bacteremia/pathology , Bacterial Adhesion , Cell Line , Gene Deletion , Gene Expression Regulation, Bacterial , Humans , Lung/immunology , Lung/microbiology , Macrophages/immunology , Mice , Mice, Inbred BALB C , Molecular Chaperones/metabolism , Pneumococcal Infections/genetics , Streptococcus pneumoniae/genetics , Streptococcus pneumoniae/immunology
15.
PLoS Pathog ; 10(9): e1004383, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25232870

ABSTRACT

Hospitalization of the elderly for invasive pneumococcal disease is frequently accompanied by the occurrence of an adverse cardiac event; these are primarily new or worsened heart failure and cardiac arrhythmia. Herein, we describe previously unrecognized microscopic lesions (microlesions) formed within the myocardium of mice, rhesus macaques, and humans during bacteremic Streptococcus pneumoniae infection. In mice, invasive pneumococcal disease (IPD) severity correlated with levels of serum troponin, a marker for cardiac damage, the development of aberrant cardiac electrophysiology, and the number and size of cardiac microlesions. Microlesions were prominent in the ventricles, vacuolar in appearance with extracellular pneumococci, and remarkable due to the absence of infiltrating immune cells. The pore-forming toxin pneumolysin was required for microlesion formation but Interleukin-1ß was not detected at the microlesion site ruling out pneumolysin-mediated pyroptosis as a cause of cell death. Antibiotic treatment resulted in maturing of the lesions over one week with robust immune cell infiltration and collagen deposition suggestive of long-term cardiac scarring. Bacterial translocation into the heart tissue required the pneumococcal adhesin CbpA and the host ligands Laminin receptor (LR) and Platelet-activating factor receptor. Immunization of mice with a fusion construct of CbpA or the LR binding domain of CbpA with the pneumolysin toxoid L460D protected against microlesion formation. We conclude that microlesion formation may contribute to the acute and long-term adverse cardiac events seen in humans with IPD.


Subject(s)
Macaca/microbiology , Myocardium/pathology , Pneumococcal Infections/immunology , Pneumococcal Infections/microbiology , Streptococcus pneumoniae/pathogenicity , Adhesins, Bacterial/metabolism , Animals , Bacterial Proteins/metabolism , Female , Immunization , Interleukin-1beta/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Myocardium/immunology , Platelet Membrane Glycoproteins/metabolism , Pneumococcal Infections/metabolism , Receptors, G-Protein-Coupled/metabolism , Receptors, Laminin/metabolism , Streptolysins/metabolism
16.
Cell Host Microbe ; 15(5): 587-599, 2014 May 14.
Article in English | MEDLINE | ID: mdl-24832453

ABSTRACT

Sickle cell disease (SCD) patients are at high risk of contracting pneumococcal infection. To address this risk, they receive pneumococcal vaccines, and antibiotic prophylaxis and treatment. To assess the impact of SCD and these interventions on pneumococcal genetic architecture, we examined the genomes of more than 300 pneumococcal isolates from SCD patients over 20 years. Modern SCD strains retained invasive capacity but shifted away from the serotypes used in vaccines. These strains had specific genetic changes related to antibiotic resistance, capsule biosynthesis, metabolism, and metal transport. A murine SCD model coupled with Tn-seq mutagenesis identified 60 noncapsular pneumococcal genes under differential selective pressure in SCD, which correlated with aspects of SCD pathophysiology. Further, virulence determinants in the SCD context were distinct from the general population, and protective capacity of potential antigens was lost over time in SCD. This highlights the importance of understanding bacterial pathogenesis in the context of high-risk individuals.


Subject(s)
Anemia, Sickle Cell/complications , Bacterial Proteins/genetics , Host-Pathogen Interactions , Pneumococcal Infections/microbiology , Streptococcus pneumoniae/genetics , Adaptation, Physiological , Adolescent , Child , Child, Preschool , Female , Genomics , Humans , Infant , Male , Molecular Sequence Data , Phylogeny , Pneumococcal Infections/etiology , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/administration & dosage , Prospective Studies , Streptococcus pneumoniae/classification , Streptococcus pneumoniae/isolation & purification , Streptococcus pneumoniae/physiology
17.
EMBO Mol Med ; 6(1): 141-54, 2014 01.
Article in English | MEDLINE | ID: mdl-24408968

ABSTRACT

Acute otitis media (AOM) caused by Streptococcus pneumoniae remains one of the most common infectious diseases worldwide despite widespread vaccination. A major limitation of the currently licensed pneumococcal vaccines is the lack of efficacy against mucosal disease manifestations such as AOM, acute bacterial sinusitis and pneumonia. We sought to generate a novel class of live vaccines that (1) retain all major antigenic virulence proteins yet are fully attenuated and (2) protect against otitis media. A live vaccine candidate based on deletion of the signal recognition pathway component ftsY induced potent, serotype-independent protection against otitis media, sinusitis, pneumonia and invasive pneumococcal disease. Protection was maintained in animals coinfected with influenza virus, but was lost if mice were depleted of CD4(+) T cells at the time of vaccination. The live vaccine induced a strong serum IgG2a and IgG2b response that correlated with CD4(+) T-cell mediated class switching. Deletion of genes required for microbial adaptation to the host environment is a novel live attenuated vaccine strategy yielding the first experimental vaccine effective against pneumococcal otitis media.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Otitis Media/prevention & control , Pneumococcal Vaccines/immunology , Acute Disease , Animals , CD4-Positive T-Lymphocytes/cytology , Chinchilla , Disease Models, Animal , Immunoglobulin Class Switching , Immunoglobulin G/blood , Mice , Mice, Inbred BALB C , Otitis Media/mortality , Otitis Media/pathology , Serotyping , Sinusitis/microbiology , Sinusitis/mortality , Sinusitis/prevention & control , Streptococcus pneumoniae/metabolism , Survival Rate , Vaccines, Attenuated/immunology , Virulence Factors/immunology
18.
J Infect Dis ; 209(7): 1116-25, 2014 Apr 01.
Article in English | MEDLINE | ID: mdl-24041791

ABSTRACT

BACKGROUND: Pneumococcus, meningococcus, and Haemophilus influenzae cause a similar spectrum of infections in the ear, lung, blood, and brain. They share cross-reactive antigens that bind to the laminin receptor of the blood-brain barrier as a molecular basis for neurotropism, and this step in pathogenesis was addressed in vaccine design. METHODS: Biologically active peptides derived from choline-binding protein A (CbpA) of pneumococcus were identified and then genetically fused to L460D pneumolysoid. The fusion construct was tested for vaccine efficacy in mouse models of nasopharyngeal carriage, otitis media, pneumonia, sepsis, and meningitis. RESULTS: The CbpA peptide-L460D pneumolysoid fusion protein was more broadly immunogenic than pneumolysoid alone, and antibodies were active in vitro against Streptococcus pneumoniae, Neisseria meningitidis, and H. influenzae. Passive and active immunization protected mice from pneumococcal carriage, otitis media, pneumonia, bacteremia, meningitis, and meningococcal sepsis. CONCLUSIONS: The CbpA peptide-L460D pneumolysoid fusion protein was broadly protective against pneumococcal infection, with the potential for additional protection against other meningeal pathogens.


Subject(s)
Bacterial Proteins/immunology , Carrier State/prevention & control , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/immunology , Streptolysins/immunology , Toxoids/immunology , Animals , Antibodies, Bacterial/blood , Bacterial Proteins/genetics , Cross Protection , Disease Models, Animal , Female , Haemophilus influenzae/immunology , Mice , Mice, Inbred BALB C , Neisseria meningitidis/immunology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Streptococcus pneumoniae/immunology , Streptolysins/genetics , Toxoids/genetics , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology
19.
J Bone Miner Res ; 27(12): 2429-37, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22991313

ABSTRACT

The Osteosarcoma Surveillance Study, an ongoing 15-year surveillance study initiated in 2003, is a postmarketing commitment to the United States (US) Food and Drug Administration to evaluate a potential association between teriparatide, rhPTH(1-34), a recombinant human parathyroid hormone analog (self-injectable medication to treat osteoporosis), and development of osteosarcoma in response to a finding from preclinical (animal) studies. Incident cases of primary osteosarcoma diagnosed in adults (aged ≥40 years) on or after January 1, 2003, are identified through population-based state, regional, and comprehensive cancer center registries in the US. Information on possible prior treatment with teriparatide, on demographics, and on risk factors is ascertained by patient or proxy telephone interview after patient consent. Between June 2004 and September 30, 2011, 1448 cases (diagnosed 2003 to 2009) were identified by participating cancer registries (estimated to be 62% of all adult cases in the US for that time period); 549 patients or proxies were interviewed. Interviewed patients were similar to noninterviewed patients with regard to mean age, sex, race, and geographical distribution and tumor type and site of tumor. Mean age of those interviewed was 61 years, 46% were female, 86% were white, and 77% were alive when the case was reported to the study investigators. Data collected in the study provide descriptive information on a large number of adults with osteosarcoma, an uncommon malignant bone tumor. After 7 years of the study, there were no osteosarcoma patients who had a prior history of teriparatide treatment. Thus, approximately halfway through this 15-year study, the study has not detected a pattern indicative of a causal association between teriparatide treatment and osteosarcoma in humans.


Subject(s)
Osteosarcoma/chemically induced , Product Surveillance, Postmarketing , Teriparatide/adverse effects , Adult , Aged , Bone Neoplasms/chemically induced , Female , Humans , Male , Middle Aged , Osteoporosis/drug therapy , Osteosarcoma/epidemiology , Parathyroid Hormone/adverse effects , Parathyroid Hormone/therapeutic use , Registries , Teriparatide/therapeutic use , United States/epidemiology
20.
PLoS Pathog ; 8(7): e1002788, 2012.
Article in English | MEDLINE | ID: mdl-22807675

ABSTRACT

Small noncoding RNAs (sRNAs) play important roles in gene regulation in both prokaryotes and eukaryotes. Thus far, no sRNA has been assigned a definitive role in virulence in the major human pathogen Streptococcus pneumoniae. Based on the potential coding capacity of intergenic regions, we hypothesized that the pneumococcus produces many sRNAs and that they would play an important role in pathogenesis. We describe the application of whole-genome transcriptional sequencing to systematically identify the sRNAs of Streptococcus pneumoniae. Using this approach, we have identified 89 putative sRNAs, 56 of which are newly identified. Furthermore, using targeted genetic approaches and Tn-seq transposon screening, we demonstrate that many of the identified sRNAs have important global and niche-specific roles in virulence. These data constitute the most comprehensive analysis of pneumococcal sRNAs and provide the first evidence of the extensive roles of sRNAs in pneumococcal pathogenesis.


Subject(s)
Pneumococcal Infections/microbiology , RNA, Bacterial/genetics , RNA, Small Untranslated/genetics , Streptococcus pneumoniae/genetics , Streptococcus pneumoniae/pathogenicity , Animals , Base Sequence , Gene Expression Regulation, Bacterial , Gene Knockout Techniques , Humans , Mice , Nucleic Acid Conformation , Pneumococcal Infections/pathology , RNA, Bacterial/chemistry , RNA, Bacterial/metabolism , RNA, Small Untranslated/chemistry , RNA, Small Untranslated/metabolism , Sequence Analysis, RNA
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