Publications by authors named "Wendy L Picking"

Article Synopsis
  • Bacillary dysentery, caused by Shigella spp., is a severe disease affecting low- and middle-income countries, especially impacting vulnerable groups like infants and the elderly through fecal-oral transmission.
  • Researchers developed a promising vaccine, L-DBF, combining key proteins that showed broad protection in mouse models, particularly for high-risk groups.
  • The study found that intranasal vaccination with L-DBF caused notable changes in the gut microbiota of young and elderly mice, suggesting vaccination can significantly influence gut health and the interaction between the immune system and gut bacteria.
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spp. are responsible for bacillary dysentery or shigellosis transmitted via the fecal-oral route, causing significant morbidity and mortality, especially among vulnerable populations. There are currently no licensed vaccines.

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(Pa) is an opportunistic bacterial pathogen responsible for severe hospital acquired infections in immunocompromised and elderly individuals. Emergence of increasingly drug resistant strains and the absence of a broad-spectrum prophylactic vaccine against both T3SA (type III secretion apparatus) and ExlA/T3SA Pa strains worsen the situation in a post-pandemic world. Thus, we formulated a candidate subunit vaccine (called ExlA/L-PaF/BECC/ME) against both Pa types.

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Shigellosis is a severe gastrointestinal disease that annually affects approximately 270 million individuals globally. It has particularly high morbidity and mortality in low-income regions; however, it is not confined to these regions and occurs in high-income nations when conditions allow. The ill effects of shigellosis are at their highest in children ages 2 to 5, with survivors often exhibiting impaired growth due to infection-induced malnutrition.

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DNA polymerases replicate cellular genomes and/or participate in the maintenance of genome integrity. DNA polymerases sharing high sequence homology with DNA polymerase I (pol I) have been grouped in Family A. Pol I participates in Okazaki fragment maturation and in bacterial genome repair.

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Shigellosis is endemic to low- and middle-income regions of the world where children are especially vulnerable. In many cases, there are pre-existing antibodies in the local population and the effect of prior exposure should be considered in the development and testing of vaccines against infection. Our study shows that L-DBF-induced immune responses are not adversely affected by prior exposure to this pathogen.

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Article Synopsis
  • - Shigellosis, a serious gastrointestinal infection, affects around 90 million people worldwide each year, but there is currently no licensed vaccine available to combat it.
  • - Researchers developed a new vaccine candidate by fusing specific proteins (DBF) from the Shigella bacterium with a mucosal adjuvant (dmLT) to create a more effective protective formulation called L-DBF.
  • - The L-DBF vaccine, when combined with a TLR4 agonist (BECC438), showed remarkable protective efficacy in mouse models, particularly when administered intranasally, resulting in strong immune responses indicated by high secretion of certain immune signaling molecules.
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Toll-like receptor (TLR) agonists are recognized as potential immune-enhancing adjuvants and are included in several licensed vaccines. Monophosphoryl lipid A (MPL®, GlaxoSmithKline) is one such TLR4 agonist that has been approved for use in human vaccines, such as Cervarix and Shingrix. Due to the heterogeneous nature of biologically derived MPL and the need for safer and more potent adjuvants, our groups have developed the novel TLR4 agonist candidates, BECC438 and BECC470 using the Bacterial Enzymatic Combinatorial Chemistry (BECC) platform.

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, a Gram-negative pathogen, has over 2500 serovars that infect a wide range of hosts. In humans, causes typhoid or gastroenteritis and is a major public health concern. In this study, SseB (the tip protein of the pathogenicity island 2 type III secretion system) was fused with the LTA1 subunit of labile-toxin from enterotoxigenic to make the self-adjuvanting antigen L-SseB.

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The opportunistic pathogen Pseudomonas aeruginosa (Pa) causes severe nosocomial infections, especially in immunocompromised individuals and the elderly. Increasing drug resistance, the absence of a licensed vaccine and increased hospitalizations due to SARS-CoV-2 have made Pa a major healthcare risk. To address this, we formulated a candidate subunit vaccine against Pa (L-PaF), by fusing the type III secretion system tip and translocator proteins with LTA1 in an oil-in-water emulsion (ME).

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is an opportunistic pathogen responsible for a wide range of infections in humans. In addition to its innate antibiotic resistance, is very effective in acquiring resistance resulting in the emergence of multi-drug resistance strains and a licensed vaccine is not yet available. We have previously demonstrated the protective efficacy of a novel antigen PaF (Pa Fusion), a fusion of the type III secretion system (T3SS) needle tip protein, PcrV, and the first of two translocator proteins, PopB.

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, causative agent of bacillary dysentery (shigellosis), uses a type III secretion system (T3SS) as its primary virulence factor. The T3SS injectisome delivers effector proteins into host cells to promote entry and create an important intracellular niche. The injectisome's cytoplasmic sorting platform (SP) is a critical assembly that contributes to substrate selection and energizing secretion.

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comprises four species of human-restricted pathogens causing bacillary dysentery. While possesses multiple genetic loci contributing to virulence, a type III secretion system (T3SS) is its primary virulence factor. The T3SS nanomachine consists of four major assemblies: the cytoplasmic sorting platform; the envelope-spanning core/basal body; an exposed needle; and a needle-associated tip complex with associated translocon that is inserted into host cell membranes.

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Infections caused by the opportunistic pathogen can be difficult to treat due to innate and acquired antibiotic resistance and this is exacerbated by the emergence of multi-drug resistant strains. Unfortunately, no licensed vaccine yet exists to prevent infections. Here we describe a novel subunit vaccine that targets the type III secretion system (T3SS).

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Many Gram-negative bacterial pathogens use type III secretion systems (T3SS) to inject proteins into eukaryotic cells to subvert normal cellular functions. The T3SS apparatus (injectisome) shares a common architecture in all systems studied thus far, comprising three major components - the cytoplasmic sorting platform, envelope-spanning basal body and external needle with tip complex. The sorting platform consists of an ATPase (SctN) connected to "pods" (SctQ) having six-fold symmetry via radial spokes (SctL).

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Shigella ssp cause bacillary dysentery (shigellosis) which has high global morbidity in young children and the elderly. The virulence of Shigella relies upon a type III secretion system (T3SS) which injects host altering effector proteins into targeted intestinal cells. The Shigella T3SS contains two components, invasion plasmid antigen D (IpaD) and invasion plasmid antigen B (IpaB), that were previously identified as broadly protective antigens.

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Many Gram-negative bacteria use type III secretion systems (T3SSs) to inject virulence effector proteins into eukaryotic cells. The T3SS apparatus (T3SA) is structurally conserved among diverse bacterial pathogens and consists of a cytoplasmic sorting platform, an envelope-spanning basal body, and an extracellular needle with tip complex. The sorting platform is essential for effector recognition and powering secretion.

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causes a severe enteric infection in infants and young children. There is no vaccine approved for use in humans. We investigated the immunogenicity and protective capacity of YopB, a conserved type III secretion system protein, alone or combined with LcrV in adult mice immunized intranasally.

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Bacterial type III secretion systems (T3SS) are used to inject proteins into mammalian cells to subvert cellular functions. The Shigella T3SS apparatus (T3SA) is comprised of a basal body, cytoplasmic sorting platform and exposed needle with needle "tip complex" (TC). TC maturation occurs when the translocator protein IpaB is recruited to the needle tip where both IpaD and IpaB control secretion induction.

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Nontyphoidal serotypes (NTS) are the leading cause of hospitalization and death due to foodborne illnesses. NTS are the costliest of the foodborne pathogens and cause ∼$4 billion annually in health care costs. In Africa, new invasive NTS are the leading cause of bacteremia, especially in HIV-positive children and adults.

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Lumazine synthase (LS) is an oligomeric enzyme involved in the biosynthesis of riboflavin in microorganisms, fungi, and plants. LS has become of significant interest to biomedical science because of its critical biological role and attractive structural properties for antigen presentation in vaccines. LS derived from Bacillus anthracis (BaLS) consists of 60 identical subunits forming an icosahedron.

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Numerous Gram-negative pathogens infect eukaryotes and use the type III secretion system (T3SS) to deliver effector proteins into host cells. One important T3SS feature is an extracellular needle with an associated tip complex responsible for assembly of a pore-forming translocon in the host cell membrane. spp.

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Polyvalent antigen display is an effective strategy to enhance the immunogenicity of subunit vaccines by clustering them in an array-like manner on a scaffold system. This strategy results in a higher local density of antigens, increased high avidity interactions with B cells and other antigen presenting cells, and therefore a more effective presentation of vaccine antigens. In this study, we used lumazine synthase (LS), an icosahedral symmetry capsid derived from Bacillus anthracis, as a scaffold to present 60 copies of a linear B cell epitope (PB10) from the ricin toxin fused to the C terminus of LS via four different linkers.

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Reducing the promiscuous tropism of native adenovirus by using fiberless adenovirus is advantageous toward its use as a gene therapy vector or vaccine component. The removal of the fiber protein on native adenovirus abrogates several undesirable interactions; however, this approach decreases the particle's physical stability. To create stable fiberless adenovirus for pharmaceutical use, the effects of temperature and pH on the particle's stability profile must be addressed.

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Shigellosis, a potentially severe bacillary dysentery, is an infectious gastrointestinal disease caused by Shigella spp. Shigella invades the human colonic epithelium and avoids clearance by promoting apoptosis of resident immune cells in the gut. This process is dependent on the Shigella type III secretion system (T3SS), which injects effector proteins into target cells to alter their normal cellular functions.

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