title: The interaction in vitro between human polymorphonuclear leukocytes and Neisseria gonorrhoeae cultivated in the chick embryo.
abstract: Cultivation of Neisseria gonorrhoeae in the allantoic cavity of 10-day chick embryos ensured the following necessary properties for subsequent quantitive in vitro phagocytosis studies of viable gonococci: log phase of growth, resistance to the cidal effect of fresh human serum, maintenance of colonial type, and absence of clumping. Employing a modification of the Maaloe technique, phagocytosis of log-phase type 1 and 2 gonococci by human PMN leukocytes did not occur in the presence or absence of serum. These findings indicate that log-phase type 1 and 2 gonococci possess antiphagocytic surface factors Stationary-phase organisms of the same colonial type were ingested and rapidly killed by human PMN leukocytes under similar experimental conditions, thus emphasizing the necessity to employ log-phase gonococci in the study of phagocytosis and antiphagocytic surface factors. Log-phase type 4 gonococci were ingested and rapidly killed by human PMN leukocytes in the presence of fresh human serum but not heat-inactivated serum or in the absence of serum. Morphologic studies demonstrated that log-phase viable gonococci attach to the surface membrane of human PMN leukocytes. Interiorization of avirulent but not virulent organisms was observed in the presence of fresh human serum. Gonococci-human PMN leukocyte interactions thus provide a model for the investigation of the nonimmunologic and immunologic parameters associated with the attachment and ingestion stages of phagocytosis.
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D002452:Cell Count; D002462:Cell Membrane / Q000276:immunology; D002470:Cell Survival; D002478:Cells, Cultured; D002642:Chick Embryo; D006801:Humans; D007962:Leukocytes / Q000276:immunology*; D008857:Microscopy, Interference; D008858:Microscopy, Phase-Contrast; D009344:Neisseria gonorrhoeae / Q000254:growth & development / Q000276:immunology*; D010587:Phagocytosis; D013210:Staphylococcus / Q000276:immunology