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Updated: Jun 19, 2026
Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens
Published on: April 5, 2019
IMMUNOLOGICAL PROPERTIES OF A TYPICAL (S-PRODUCING) AND A DEGRADED (NON-S-PRODUCING) STRAIN OF TYPE II PNEUMOCOCCUS
E L Gaspari1, W L Fleming, J M Neill
1Department of Bacteriology and Immunology, Vanderbilt University Medical School, Nashville.
The loss of the specialized function of S production by Type II pneumococcus was accompanied by a loss of the antigenic properties involved in both active and passive protection of mice. Absorption of Type II serum with S-producing pneumococci removed all the protective antibodies, as well as the type-specific agglutinins and S precipitins. The same absorption treatment of the serum by non-S-producing pneumococci failed entirely to remove the type-specific antibodies and did not affect the protective value of the serum. Absorption with bacteria-free culture fluids containing the reactive carbohydrate removed the protective antibodies as completely as absorption with the whole bacterial cells of type-specific strains. The results taken as a whole indicate that the antibodies involved in the usual protection of mice against Type II pneumococci are closely related, if not identical, to the specific anticarbohydrate precipitin.
The loss of the specialized function of S production by Type II pneumococcus was accompanied by a loss of the antigenic properties involved in both active and passive protection of mice. Absorption of Type II serum with S-producing pneumococci removed all the protective antibodies, as well as the type-specific agglutinins and S precipitins. The same absorption treatment of the serum by non-S-producing pneumococci failed entirely to remove the type-specific antibodies and did not affect the protective value of the serum. Absorption with bacteria-free culture fluids containing the reactive carbohydrate removed the protective antibodies as completely as absorption with the whole bacterial cells of type-specific strains. The results taken as a whole indicate that the antibodies involved in the usual protection of mice against Type II pneumococci are closely related, if not identical, to the specific anticarbohydrate precipitin.
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