ABSTRACT
The immunogenicity of the soluble phase I antigen of Coxiella burnetii for guinea pigs was enhanced by a nuclease-resistant complex of polyriboinosinic-polyribocytidylic acid, poly-L-lysine, and carboxymethyl cellulose.
Subject(s)
Antibodies, Bacterial/biosynthesis , Antigens, Bacterial/administration & dosage , Coxiella/immunology , Animals , Bacterial Vaccines/administration & dosage , Carboxymethylcellulose Sodium/administration & dosage , Guinea Pigs , Poly I-C/administration & dosage , Polylysine/administration & dosage , Q Fever/prevention & controlABSTRACT
The pronounced change in the buoyant density of Coxiella burnetii in CsCl gradients that was caused by treatment with formalin or ultraviolet radiation was not observed with Rickettsia rickettsii.
Subject(s)
Coxiella , Rickettsia rickettsii , Centrifugation, Density Gradient , Coxiella/drug effects , Coxiella/radiation effects , Formaldehyde/pharmacology , Rickettsia rickettsii/drug effects , Rickettsia rickettsii/radiation effects , Ultraviolet RaysSubject(s)
Antigens, Bacterial/isolation & purification , Bacterial Vaccines , Coxiella/immunology , Sulfites , Animals , Antibodies, Bacterial/analysis , Antibody Formation , Chemical Precipitation , Complement Fixation Tests , Edetic Acid , Guinea Pigs , Q Fever/prevention & control , Solubility , Trichloroacetic AcidABSTRACT
Coxiella burneti phase I, purified from a formalin-inactivated yolk-sac vaccine, was separated into two bands of morphologically distinct cell types when subjected to sucrose gradient centrifugation. Recycling of the less dense, rod-shaped cells in unbuffered sucrose gradients (pH 5.5 to 6.0) resulted in the formation of bands having the location and appearance of the original two bands. Recycling of the denser band of larger ovoid-shaped cells yielded a single band, suggesting that the larger cell type arose from the smaller cell. In contrast to vaccine-derived rickettsiae, live, cell culture-propagated phase I organisms formed a single band in unbuffered sucrose gradients, at the same density as the upper band of the vaccine preparation. Centrifugation of cell culture-derived rickettsiae for 26 to 48 h in sucrose gradients of pH 5.5 resulted in the formation of a second band, at the same density as the lower band of the vaccine preparation. This did not occur in gradients of pH 7.0. Treatment of cell culture-propagated rickettsiae with formalin or germicidal ultraviolet radiation induced a total shift of the less dense cell population to a zone of higher density when centrifuged isopycnically in CsC1 gradients. This density change did not occur in sucrose gradients, suggesting a difference in the effect of these treatments on the permeability of the cell membrane to sucrose and CsC1.
