EFFECT OF CYTOPHILIC IGG2 ON PHAGOCYTOSIS BY OVINE POLYMORPHONUCLEAR LEUKOCYTES

  • 1 January 1976
    • journal article
    • research article
    • Vol. 31  (2) , 159-165
Abstract
Non-lactating, multiparous ewes were immunized either by s.c. infection with live Staphylococcus aureus (17 ewes) or by i.m. injections of a killed S. aureus-oil adjuvant vaccine (17 ewes). Polymorphs which were subsequently collected from the mammary glands of the animals were used in in vitro phagocytosis assays against Pseudomonas sp. or S. aureus. There was no difference between polymorphs from the 2 groups of ewes in their ability to phagocytose Pseudomonas. Polymorphs from the infected ewes showed significant phagocytic superiority over cells from ewes given the killed vaccine when S. aureus was the target organism. This phagocytic superiority could be abrogated by removal of cytophilic immunoglobulin [Ig] from polymorphs and restored by replacement of cytophilic Ig. Staining of polymorphs with FITC[fluorescein isothiocyanate]-conjugated anti-Ig sera showed that cytophilic Ig on the surface of polymorphs belonged to the IgG2 class. When neutral polymorphs (from non-immunized ewes) were coated with IgG2 purified from the sera of infected ewes, they exhibited enhanced phagocytosis of staphylococci compared with neutral polymorphs carrying IgG2 from the sera of ewes given the killed vaccine.