FLOW-CYTOMETRIC STUDIES OF THE PHAGOCYTIC CAPACITIES OF EQUINE NEUTROPHILS

Citation
A. Johannisson et al., FLOW-CYTOMETRIC STUDIES OF THE PHAGOCYTIC CAPACITIES OF EQUINE NEUTROPHILS, Acta veterinaria Scandinavica, 36(4), 1995, pp. 553-562
Citations number
25
Categorie Soggetti
Veterinary Sciences
ISSN journal
0044605X
Volume
36
Issue
4
Year of publication
1995
Pages
553 - 562
Database
ISI
SICI code
0044-605X(1995)36:4<553:FSOTPC>2.0.ZU;2-P
Abstract
Methodological aspects of flow-cytometric evaluation of the phagocytic properties of equine neutrophils were elucidated. The kinetics of att achment and ingestion were studied, and the phagocytic process was mor e rapidly completed when serum-opsonized yeast cells were used than wi th use of IgG-opsonized yeast cells. Trypan blue was successfully used to quench fluorescence of non-ingested yeast cells. There were only m inor differences in the kinetics of phagocytosis between quenched and unquenched samples, indicating that attachment is rapidly followed by ingestion. Trypan blue quenching caused loss of cells with light scatt ering properties of granulocytes, although this did not affect the det ermined frequencies of truly phagocytic neutrophils. Aggregation of ye ast cells proved to be a disturbance but not an obstacle to the determ ination of frequencies of actively phagocytic cells. Flow cytometry is well suited for studies of phagocytosis of yeast cells by equine neut rophils, and the trypan blue quenching provides a means of eliminating false-positive events due to aggregation of yeast cells. The main adv antage of the flow-cytometric method is the possibility of rapid proce ssing of a large number of samples, making the method useful for studi es of herds.