Characterization of camel leukocytes by flow cytometry and microscopic evaluation of granulocyte phagocytosis of fluorescent bacteria.

Peripheral blood was obtained from four lactating camels (Camelus bactrianus) and flow cytometry was used to characterize cell populations. The ability of the granulocytes to engulf fluorescent bacteria was studied in vitro using fluorescence microscopy. Three clusters of blood cells (mononuclear cells, neutrophils and eosinophils) were identified by flow cytometry and fluorescent microscopy. Milk, on the other hand, was dominated by cell fragments and no distinct cluster formation was found. The mean yield of blood granulocytes and monocytes isolated on Ficoll gradient was 92.2 +/- 5.4% and 7.9 +/- 5.7%, respectively. Cell viability was 95%. The mean percentage of phagocytic cells was 71.8 +/- 5.9% at 10 min and increased to 97.3 +/- 0.5% at 60 min when observation was terminated. The average number of bacteria per phagocyte was 8.7 +/- 2.1 and 13.1 +/- 0.9 at 10 and 60 min incubation time.