title: Influence of Rhodococcus equi on the respiratory burst of resident alveolar macrophages from adult horses.
abstract: Opsonized Rhodococcus equi activated the respiratory burst of resident alveolar macrophages (AM) from adult horses in a logarithmic-linear, mass-related manner. The effect of R equi was not significantly different from that of equal masses of opsonized zymosan A. Therefore, R equi does not appear to attenuate the respiratory burst of equine AM. The stimulatory effect of R equi was not reflected by increased production of superoxide anion (O2-), but increased activity of the hexose monophosphate shunt was observed. These results suggest a similarity between the respiratory burst of AM from horses and that of AM from rabbits. We concluded that resident AM from adult horses do not produce O2- concurrently with an increase in activity of the hexose monophosphate shunt when stimulated with either opsonized zymosan A or opsonized R equi. This suggests that O2- is not an important component of the antibacterial defenses of equine AM. Whether equine AM are incapable of producing O2- or require different stimuli to produce it was not determined.
authors.affiliation: Department of Veterinary Biosciences, College of Veterinary Medicine, University of Illinois, Urbana 61801.
authors.forename: G W
authors.initials: GW
authors.lastname: Brumbaugh
authors.forename: L E
authors.initials: LE
authors.lastname: Davis
authors.forename: J C
authors.initials: JC
authors.lastname: Thurmon
authors.forename: D C
authors.initials: DC
authors.lastname: Savage
mesh_terms: D000818:Animals; D004112:Dimercaprol; D005260:Female; D006736:Horses; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D009895:Opsonin Proteins; D010101:Oxygen Consumption; D010427:Pentose Phosphate Pathway; D012240:Rhodococcus / Q000254:growth & development / Q000502:physiology*; D013997:Time Factors; D015054:Zymosan
chemical_list: D009895:Opsonin Proteins; D004112:Dimercaprol; D015054:Zymosan