James A. Roth

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A direct, rapid, quantitative colorimetric assay to determine neutrophil primary granule degranulation was adapted for use with bovine neutrophils. The assay measures the exocytosis of myeloperoxidase (MPO) using 3,3',5,5'-tetramethylbenzidine as a substrate. The assay was validated by evaluating the effects of various stimulants and inhibitors of(More)
A collection of swine, fish, and cetacean Erysipelothrix rhusiopathiae strains representing 16 serotypes was analyzed for possession of the three currently recognized surface protective antigen (spa)-types: spaA, spaB, and spaC. Polymerase chain reaction (PCR) assays and Western blotting with a SpaA-specific monoclonal antibody demonstrated that spa-type is(More)
The objective of this report was to characterize the enhanced clinical disease and lung lesions observed in pigs vaccinated with inactivated H1N2 swine δ-cluster influenza A virus and challenged with pandemic 2009 A/H1N1 human influenza virus. Eighty-four, 6-week-old, cross-bred pigs were randomly allocated into 3 groups of 28 pigs to represent(More)
Neutrophils are an important component of host defence against many bacterial, viral and fungal infections, and the evaluation of neutrophil function is valuable for assessment of health status [1]. Some literature is non-specific or contradictory about the classification of leucocyte morphology in fish, since morphology alone can vary by species [2e4].(More)
Lymphocytes from 8 Holstein heifers were evaluated during the periparturient period for mitogen-induced lymphocyte blastogenic responses. Phytohemagglutinin P- and concanavalin A-induced lymphocyte blastogenesis increased 2 and 3 weeks before parturition, respectively. However, by the first week after parturition, lymphocyte blastogenesis was markedly(More)
Interest in the use of recombinant cytokines for immunotherapy is increasing as more information becomes available on the influences of these products on effector cells (e.g., neutrophils) involved in the resistance of the host to disease. This review summarizes the information available on in vitro and in vivo activation of neutrophils by recombinant(More)
A direct, rapid, quantitative colorimetric assay to determine neutrophil primary granule degranulation was adapted for use with fathead minnow kidney neutrophils. The assay measures the exocytosis of myeloperoxidase (MPO) using 3,3',5,5'-tetramethylbenzidine as a substrate. The assay was validated by comparing the total myeloperoxidase content of neutrophil(More)
Neutrophils from 8 Holstein heifers were evaluated for function during the periparturient period. Random migration, ingestion of bacteria, superoxide anion production, native (nonenhanced) chemiluminescence, iodination, and antibody-dependent, cell-mediated cytotoxicity by neutrophils were determined. Foremilk samples were evaluated for bacteria.(More)
The early pathogenic effects of bovine immunodeficiency-like virus (BIV) were studied in calves experimentally inoculated with BIV. All animals inoculated with BIV R29-infected cells seroconverted by 6 weeks postinoculation, and BIV was recoverable from each animal at 2 weeks postinoculation. However, levels of BIV replication in vivo appeared to be low. In(More)
Five methods for measurement of phagocytosis and respiratory burst activity of bovine blood polymorphonuclear leukocytes (PMNs) were evaluated. Eight cows were repeatedly sampled over a two week period and parallel samples tested in all five assays to assess the repeatability and stability of the methods. In the flow cytometric phagocytosis assay, ingestion(More)