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.