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Bovine Neutrophil (bovine + neutrophil)
Selected AbstractsCharacterization of bovine neutrophil ,2 -adrenergic receptor functionJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2010T. P. LaBRANCHE LaBranche, T. P., Ehrich, M. F., Eyre, P. Characterization of bovine neutrophil ,2 -adrenergic receptor function. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365-2885.2009.01143.x. This study compares bovine leukocyte ,-adrenergic receptor densities to that of the rat, demonstrates for the first time a functional ,2 -adrenergic receptor signaling pathway in steer neutrophils, and investigates the effect of an inflammatory stimulus on that signaling pathway. The ,1 -/,2 -adrenergic antagonist [3H]CGP-12177 demonstrated that rat lymphocyte specific binding-site density was highest, followed by steer and dairy cow lymphocytes, and lastly steer and dairy cow neutrophils. The ,2 -adrenergic agonist terbutaline stimulated steer neutrophil adenosine 3,5-cyclic monophosphate (cAMP) production, an effect increased by inclusion of ,1 × 10,8 m phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C. Both terbutaline and the nonselective phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) independently decreased steer neutrophil superoxide anion production in a concentration-dependent manner, with 1 × 10,4 m IBMX enhancing both the potency and efficacy of the terbutaline effect (up to 74% reduction in superoxide anion production). Superoxide anion production was also reduced by the synthetic cAMP analog 8-bromo-cAMP, which increased the potency of the IBMX effect on superoxide anion production. Taken together, these data demonstrate the presence of a ,2 -adrenergic receptor signaling pathway in bovine neutrophils much like that described in other animal species, as well as the potential for an inflammatory stimulus to alter its function. [source] Successful Six-Day Kidney Preservation Using Trophic Factor Supplemented Media and Simple Cold StorageAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2002Jonathan F. McAnulty This study examined the effect of trophic factor supplementation [TFS; bovine neutrophil peptide-1 (bactenecin), 1 mg/L; substance P, 2.5 mg/L; nerve growth factor, 20 ,g/L; epidermal growth factor, 10 ,g/L; insulin-like growth factor-1, 10 ,g/L] during cold storage with UW lactobionate solution. Dogs transplanted with kidneys stored for 4 days in TFS-UW had significantly lower peak serum creatinine values (mean 2.9 ± 0.2 mg/dL) and returned to normal values faster (6 days) than kidneys stored for 3 days in unmodified UW solution (4.2 ± 0.3 mg/dL and 14 days, respectively). Kidneys stored for 5 days in TFS-UW (mean peak creatinine 3.7 ± 0.3) functioned equivalently to kidneys stored for 3 days and better than kidneys stored for 4 days in UW alone. Dogs with kidneys stored for 6 days in TFS-UW had mean peak creatinines of 5.7 ± 0.4 mg/dL. These returned to normal creatinine values in 14 days, equal to 3-day stored and significantly better than kidneys stored for 4 days in UW alone (20 days recovery time). This study shows trophic factor deprivation appears to be a critical mechanism of injury in organ preservation with current synthetic storage media, and marks the initial development of a synthetic biologically active preservation solution, the next generation of preservation media. [source] Characterization of bovine neutrophil ,2 -adrenergic receptor functionJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2010T. P. LaBRANCHE LaBranche, T. P., Ehrich, M. F., Eyre, P. Characterization of bovine neutrophil ,2 -adrenergic receptor function. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365-2885.2009.01143.x. This study compares bovine leukocyte ,-adrenergic receptor densities to that of the rat, demonstrates for the first time a functional ,2 -adrenergic receptor signaling pathway in steer neutrophils, and investigates the effect of an inflammatory stimulus on that signaling pathway. The ,1 -/,2 -adrenergic antagonist [3H]CGP-12177 demonstrated that rat lymphocyte specific binding-site density was highest, followed by steer and dairy cow lymphocytes, and lastly steer and dairy cow neutrophils. The ,2 -adrenergic agonist terbutaline stimulated steer neutrophil adenosine 3,5-cyclic monophosphate (cAMP) production, an effect increased by inclusion of ,1 × 10,8 m phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C. Both terbutaline and the nonselective phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) independently decreased steer neutrophil superoxide anion production in a concentration-dependent manner, with 1 × 10,4 m IBMX enhancing both the potency and efficacy of the terbutaline effect (up to 74% reduction in superoxide anion production). Superoxide anion production was also reduced by the synthetic cAMP analog 8-bromo-cAMP, which increased the potency of the IBMX effect on superoxide anion production. Taken together, these data demonstrate the presence of a ,2 -adrenergic receptor signaling pathway in bovine neutrophils much like that described in other animal species, as well as the potential for an inflammatory stimulus to alter its function. [source] New indolicidin analogues with potent antibacterial activity,CHEMICAL BIOLOGY & DRUG DESIGN, Issue 5 2004T.S. Ryge Abstract:, Indolicidin is a 13-residue antimicrobial peptide amide, ILPWKWPWWPWRR-NH2, isolated from the cytoplasmic granules of bovine neutrophils. Indolicidin is active against a wide range of microorganisms and has also been shown to be haemolytic and cytotoxic towards erythrocytes and human T lymphocytes. The aim of the present paper is two-fold. First, we examine the importance of tryptophan in the antibacterial activity of indolicidin. We prepared five peptide analogues with the format ILPXKXPXXPXRR-NH2 in which Trp-residues 4,6,8,9,11 were replaced in all positions with X = a single non-natural building block; N -substituted glycine residue or nonproteinogenic amino acid. The analogues were tested for antibacterial activity against both Staphylococcus aureus American type culture collection (ATCC) 25923 and Escherichia coli ATCC 25922. We found that tryptophan is not essential in the antibacterial activity of indolicidin, and even more active analogues were obtained by replacing tryptophan with non-natural aromatic amino acids. Using this knowledge, we then investigated a new principle for improving the antibacterial activity of small peptides. Our approach involves changing the hydrophobicity of the peptide by modifying the N-terminus with a hydrophobic non-natural building block. We prepared 22 analogues of indolicidin and [Phe4,6,8,9,11] indolicidin, 11 of each, carrying a hydrophobic non-natural building block attached to the N-terminus. Several active antibacterial analogues were identified. Finally, the cytotoxicity of the analogues against sheep erythrocytes was assessed in a haemolytic activity assay. The results presented here suggest that modified analogues of antibacterial peptides, containing non-natural building blocks, are promising lead structures for developing future therapeutics. [source] | ||||||||||