PHAGOLYSOSOMAL PH OF HUMAN-NEUTROPHILS

  • 1 January 1984
    • journal article
    • research article
    • Vol. 63  (1) , 88-95
Abstract
Human neutrophils sequester yeast cells or zymosan particles in 2 classes of phagocytic vacuoles: sealed and unsealed. The pH of sealed vacuoles was measured by a newly devised fluorometric procedure that used fluoresceinated zymosan particles, derived from Saccharomyces cerevisiae, as a pH probe. Five min after initiation of phagocytosis, sealed vacuoles were alkaline, exhibiting a pH of 7.80 .+-. 0.19 (mean .+-. SEM[standard error of the mean]). Their acidity subsequently increased, so that the pH fell to 7.38 .+-. 0.25 after 15 min, 6.35 .+-. 0.35 after 30 min, and 5.68 .+-. 0.26 after 60 min. The implications of these findings for neutrophil microbicidal mechanisms are discussed.