A Study on Immune Response to Cryptococcus Neoformans Antigens in Rabbits

Abstract

A study on immune response to Cryptococcus neoformans antigens was done in rabbits.  Three different doses of encapsulated C. neoformans antigens, 1.5x10⁷, 1.5x10⁸ and 1.5x10⁹ cells/milliliter respectively, were injected intravenously via ear vein.  Results showed that the concentration of 1.5x10⁸ cells/milliliter stimulated high agglutination titers of antibody i.e., 1024 in one rabbit and 32768 in the other.  For comparison, the titer of antiserum obtained from rabbits immunized with 1.5x10⁷ cells/milliliter did not exceed 64, while the dose of 1.5x10⁹ cells/milliliter killed rabbits.  Results suggested that a high quantity of anti-C. neoformans antiserum could be prepared in rabbits.  This antiserum would be an important reagent in the development of the serological test kit for Cryptococcal diagnosis.

KEY WORD : Cryptococcus neoformans, Antibody response.