Antibodies against Aspergillus fumigatus. I. Standardization of the antigenic composition.

Three different stages were found during growth of Aspergillus fumigatus as characterized by the changes in pH of the medium: (1) An acidic phase (phase I); (2) a second phase (phase II) during which the pH rises till values around pH = 8.5; (3) a third phase (phase III) during which the pH remains constant or drops slightly. During phase I a fast appearance of certain antigenic components was found that is ascribed to an active process of excretion. Additional antigenic components appeared in the culture medium after lysis of the microorganisms (phases II and III). Lysis of the microorganisms and appearance of antigenic components are dependent on the glucose concentration of the medium.