Enhancing sensitivity of lateral flow assay with application to SARS-CoV-2.

Lateral flow assay (LFA) has long been used as a biomarker detection technique. It has advantages such as low cost, rapid readout, portability, and ease of use. However, its qualitative readout process and lack of sensitivity are limiting factors.

Equine hyperimmune serum protects mice against Clostridium difficile spore challenge.

Clostridium (C.) difficile is a common cause of nosocomial diarrhea in horses. Vancomycin and metronidazole have been used as standard treatments but are only moderately effective, which highlights the need for a novel alternative therapy.

Evaluation of a Mycobacterium avium subsp. paratuberculosis leuD mutant as a vaccine candidate against challenge in a caprine model.

Johne's disease (JD) is prevalent worldwide and has a significant impact on the global agricultural economy. In the present study, we evaluated the protective efficacy of a leuD (Δleud) mutant and gained insight into differential immune responses after challenge with virulent M. avium subsp.

Elastin, a novel extracellular matrix protein adhering to mycobacterial antigen 85 complex.

The antigen 85 complex (Ag85) consists of three predominantly secreted proteins (Ag85A, Ag85B, and Ag85C), which play a key role in the mycobacterial pathogenesis and also possess enzymatic mycolyltransferase activity involved in cell wall synthesis. Ag85 is not only considered to be a virulence factor because its expression is essential for intracellular survival within macrophages, but also because it contributes to adherence, invasion, and dissemination of mycobacteria in host cells. In this study, we report that the extracellular matrix components, elastin and its precursor (tropoelastin) derived from human aorta, lung, and skin, serve as binding partners of Ag85 from Mycobacterium tuberculosis.

Temporal differential proteomes of Clostridium difficile in the pig ileal-ligated loop model.

The impact of Clostridium difficile infection (CDI) on healthcare is becoming increasingly recognized as it represents a major cause of nosocomial diarrhea. A rising number of CDI cases and outbreaks have been reported worldwide. Here, we developed the pig ileal-ligated loop model for semi-quantitative analysis comparing temporal differential proteomes in C.

Immune response and protective efficacy of live attenuated Salmonella vaccine expressing antigens of Mycobacterium avium subsp. paratuberculosis against challenge in mice.

Mycobacterium avium subsp. paratuberculosis (MAP) causes chronic granulomatous enteritis in ruminants that leads to diarrhea and eventually death. Existing vaccines have proven useful in limiting disease progression but have not been effective in preventing infection.

Immunogenicity and protective efficacy of the Mycobacterium avium subsp. paratuberculosis attenuated mutants against challenge in a mouse model.

Johne's disease (JD), caused by Mycobacterium avium subsp. paratuberculosis (MAP), results in serious economic losses worldwide especially in cattle, sheep and goats. To control the impact of JD on the animal industry, an effective vaccine with minimal adverse effects is urgently required.

Evaluation of novel fusion proteins derived from extracellular matrix binding domains of LigB as vaccine candidates against leptospirosis in a hamster model.

Leptospira binds to host extracellular matrix (ECM) through surface exposed outer membrane proteins called adhesin in order to initiate infection. Of various adhesins present on the surface of the spirochete, Leptospira-immunoglobulin like proteins (Lig proteins) and LipL32 are most abundant, widely distributed among pathogenic serovars and well characterized. Various fragments of Lig proteins (Ligcon4, Ligcon4-7.

Analysis of Escherichia coli O157 clinical isolates by multilocus sequence typing.

Background: Although many strain typing methods exist for pathogenic Escherichia coli, most have drawbacks in terms of resolving power, interpretability, or scalability. For this reason, multilocus sequence typing (MLST) is an appealing alternative especially when applied to the typing of temporal and spatially separated isolates. This method relies on an unambiguous DNA sequence analysis of nucleotide polymorphisms in housekeeping genes and has shown a high degree of intraspecies discriminatory power for bacterial and fungal pathogens.

Identification and characterization of OmpA-like proteins as novel vaccine candidates for Leptospirosis.

Leptospira is an important infectious Gram-negative bacterium causing Leptospirosis in mammals. Outer membrane proteins (OMPs) are key molecules in the interface between the cell and its environment. A group of putative leptospiral outer membrane proteins with an OmpA-like domain, comprising Lp0056, Lp0222, Lp3615, Lp3685, Lp4337 and Lbp328, were identified by bioinformatic methods and expressed as GST-tag fusion proteins.

Evaluation of immune responses and protective efficacy in a goat model following immunization with a coctail of recombinant antigens and a polyprotein of Mycobacterium avium subsp. paratuberculosis.

The protective efficacy of four recombinant antigens (85A, 85B, superoxide dismutase [SOD], and a fusion polypeptide [Map74F]) of Mycobacterium avium subsp. paratuberculosis (MAP) along with the adjuvant dimethydioctadecyl ammonium bromide (DDA) was assessed in a goat challenge model. Animals were immunized with the four antigens with adjuvant DDA (Group I, eight goat kids) or without the adjuvant (Group II, eight goat kids) or adjuvant only (Group III, nine goat kids).

Immunization with a DNA vaccine cocktail induces a Th1 response and protects mice against Mycobacterium avium subsp. paratuberculosis challenge.

Several antigens of Mycobacterium avium subsp. paratuberculosis have been studied as vaccine components and their immunogenicity has been evaluated. Previously, we reported that 85 antigen complex (85A, 85B, and 85C), superoxide dismutase (SOD), and 35kDa protein could induce significant lymphocyte proliferation as well as the elaboration of Th1-associated cytokines including interferon gamma (IFN-gamma), interleukin-2 (IL-2), IL-12 and tumor necrosis factor alpha (TNF-alpha).

Vaccination with recombinant Mycobacterium avium subsp. paratuberculosis proteins induces differential immune responses and protects calves against infection by oral challenge.

We previously reported the in vitro cellular immune responses to recombinant antigens (rAgs) of Mycobacterium avium subsp. paratuberculosis (MAP). Here we report the differential immune responses and protective efficacy of four rAgs of MAP (85A, 85B, 85C, and superoxide dismutase (SOD)) used with two adjuvants (monophosphoryl lipid A (MPLA) containing synthetic trehalose dicorynomycolate, cell wall skeleton (MPLA) and bovine IL-12), against MAP challenge in calves.

Immune responses in mice to Mycobacterium avium subsp. paratuberculosis following vaccination with a novel 74F recombinant polyprotein.

Johne's disease (JD) is a chronic infectious disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). Here, we report the cloning and expression of a 74kDa recombinant polyprotein (Map74F) and its protective efficacy against MAP infection in mice.

Molecular characterization of Listeria monocytogenes from natural and urban environments.

Characterization of 80 Listeria monocytogenes isolates from urban and natural environments differentiated 7 and 26 EcoRI ribotypes, respectively. Whereas the majority of isolates from the natural environment represented L. monocytogenes lineage II (12 of 13 isolates), urban isolates grouped evenly into lineages I and II (32 and 33 isolates, respectively) and included two lineage III isolates.

Evaluation of risk factors for the spread of low pathogenicity H7N2 avian influenza virus among commercial poultry farms.

Objective: To identify risk factors associated with the spread of low pathogenicity H7N2 avian influenza (AI) virus among commercial poultry farms in western Virginia during an outbreak in 2002.

Design: Case-control study.

Procedure: Questionnaires were used to collect information about farm characteristics, biosecurity measures, and husbandry practices on 151 infected premises (128 turkey and 23 chicken farms) and 199 noninfected premises (167 turkey and 32 chicken farms).

Survey of antimicrobial susceptibility testing practices of veterinary diagnostic laboratories in the United States.

Objective: To describe antimicrobial susceptibility testing practices of veterinary diagnostic laboratories in the United States and evaluate the feasibility of collating this information for the purpose of monitoring antimicrobial resistance in bacterial isolates from animals.

Design: Cross-sectional study.

Procedures: A questionnaire was mailed to veterinary diagnostic laboratories throughout the United States to identify those laboratories that conduct susceptibility testing.