title: Ultrastructural observation on the bacterial capsule of Bacillus anthracis seen in the spleen of a diseased cow.
abstract: The bacterial capsule of Bacillus anthracis seen in the spleen of a cow which had died of anthrax was studied electron microscopically. It was visible around bacteria which had been fixed in a ruthenium red-containing fixative. It was composed of electron-dense spikes and extended outwards from the bacterial surface. It was not found around bacteria which had been treated with a fixative devoid of ruthenium red. Bacteria were seen scattered among blood cells. They were not phagocytized by neutrophils or macrophages.
mesh_terms: D000818:Animals; D000881:Anthrax / Q000382:microbiology / Q000662:veterinary*; D001408:Bacillus anthracis / Q000648:ultrastructure*; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D005260:Female; D013154:Spleen / Q000382:microbiology*