Antigens from Yeast Phase of Histoplasma capsulatum. II. Immunologic Properties of Protoplasm vs. Cell Walls

Abstract

A technique, involving the use of the Mickle tissue disintegrator and the electron microscope, was described for the separation of the cell wall and the internal protoplasm from the cells of the yeast phase of Histoplasma capsulatum. The cell wall contained the antigenic activity associated with the protection of mice against lethal intracerebral challenge, as well as with complement fixation and toxicity. Sensitized animals, on the other hand, showed a delayed type of reaction to either fraction. The protoplasm was more active than the cell wall in the hemolysis of guinea pig erythrocytes.