Oxidative metabolism of chicken polymorphonuclear leucocytes during phagocytosis

Abstract

The oxidative response to phagocytosis by chicken polymorphonuclear leucocytes was investigated as compared to guinea pig polymorphonuclear leucocytes. The polymorphs from both species respond to phagocytosis with an increased oxygen consumption, an increased generation of O2 and H2O2, and an increased oxidation of glucose through the hexose monophosphate shunt. The rate of oxygen consumption, and generation of O2- and H2O2 by phagocytosing chicken polymorphonuclear leucocytes is considerably lower than with phagocytosing guinea pig polymorphonuclear leucocytes. By contrast, the extent of hexose monophosphate shunt stimulation in chicken polymorphs is comparable to that of guinea pig polymorphs. Evidence is presented suggesting that H2O2 is preferentially degraded in chicken cells through the glutathione cycle, whereas catalase and myeloperoxidase are the two main H2O2 degrading enzymes in guinea pig cells. The 20,000 g fraction of the postnuclear supernatant of chicken polymorphs contains a cyanide-insensitive NADPH oxidizing activity which is stimulated during phagocytosis. Similar properties for the NADPH oxidizing activity of guinea pig polymorphs have been previously reported. It is concluded that the metabolic burst of phagocytosing chicken polymorphonuclear leucocytes is qualitatively similar to that of guinea pig polymorphonuclear leucocytes, but the latter cells are more active in all the biochemical parameters that have been measured. The difference in the H2O2 degradation pathways between the two species is accounted for by the lack of myeloperoxidase and catalase in chicken polymorphs.

Neutrophil-endothelial cell interaction. Evidence for and mechanisms of the self-protection of bovine microvascular endothelial cells from hydrogen peroxide-induced oxidative stress.

“…Performed on total cell homogenate, these assays used aliquots of the suspension of freshly isolated MEC or PMN that were washed twice and resuspended in ice-cold KRP. Homogenization was then performed as previously described for polymorphonuclear leukocytes (11). The homogenate was diluted in KRP and immediately assayed for enzymatic activities at 370C.…”

Cellular immune response of pigeons in the conditions of endotoxin fever and pyrogenic tolerance

“…In response to LPS the enhanced production of oxygen reactive forms, i.e. superoxide radical or hydrogen peroxide, by avian polymorphonuclear leucocytes is also present, similarly to mammalian counterparts (Dri et al 1978). Therefore both heterophils and macrophages are probably involved in the first-line host defence (Cadenas 1989, Ziprin 1997.…”