A PROPOSAL FOR PURIFICATION OF SALIVARY POLYMORPHONUCLEAR LEUKOCYTES BY COMBINATION OF NYLON MESH FILTRATION AND DENSITY-GRADIENT METHOD - A VALIDATION BY SUPEROXIDE-GENERATING AND CYCLIC AMP-GENERATING RESPONSES

Isolation and purification of salivary polymorphonuclear leukocytes (S PMNs) from accompanying epithelial cells was presented by using a dens ity-gradient method with Ficoll. SPMNs samples prepared by already est ablished methods (nylon mesh filtration) was compared with SPMNs sampl es after further purification by Ficoll (d=1.083). Microscopically, SP MNs samples after nylon mesh filtration contain higher percentage of e pithelial cells than SPMNs samples after Ficoll centrifugation. In res ponse to stimulation of superoxide generation, both samples showed the same pattern of response. However, in response to forskolin and prost aglandin E1, cyclic AMP levels in samples after nylon mesh purificatio n were significantly higher than in samples after Ficoll purification because of the presence of contaminating epithelial cells. We can conc lude that, although nylon mesh filtration is satisfactory when we need to examine superoxide generation but further purification is necessar y when we want to measure factors like intracellular cyclic AMP format ion.