Karen M Sipes

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Peroxynitrite is a potent oxidant generated from the reaction of nitric oxide (NO) and superoxide anion (O2-), both of which can be produced in inflammatory tissues. In these studies, we analyzed what direct effect peroxynitrite had on neutrophil (PMN) function. We found that peroxynitrite was an effective priming agent for PMNs, as demonstrated by enhanced(More)
Neutrophils play an essential role in the cellular defense of the bovine mammary gland and compromised leukocyte function has been linked to the development of bovine mastitis. During mastitis, large numbers of leukocytes migrate into the mammary tissues where they become activated, resulting in the assembly of neutrophil membrane and cytosolic proteins to(More)
We characterized the dose response of bovine neutrophils to platelet-activating factor (PAF) with respect to the following functions: calcium flux and membrane potential changes, actin polymerization, degranulation, and the production and/or priming of the oxidative burst. PAF at very low concentrations (10(-10) and 10(-9) M) caused changes in intracellular(More)
OBJECTIVE To analyze surface antigen expression and functional responses of leukocytes from calves heterozygous and homozygous for bovine leukocyte adhesion deficiency (BLAD). ANIMALS 8 clinically normal calves, 4 calves heterozygous for BLAD, and 4 calves homozygous for BLAD. PROCEDURE Surface antigen expression was examined by flow cytometric analysis(More)
Adenosine is a potent inhibitor of reactive oxygen species (ROS) production by the NADPH oxidase in fMLF-stimulated neutrophils. Although much is known about the pharamacology and signal transduction of this effect, it is not known how adenosine affects assembly and localization of the NADPH oxidase components within the neutrophil. We report here that(More)
A prerequisite for studies on bovine neutrophils is a reliable method of neutrophil isolation from blood to obtain highly purified cell populations that are functionally active. Since current techniques of neutrophil isolation fall short of these requirements, we have developed a newer and more effective technique for isolation of bovine neutrophils that(More)
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