THE MECHANISM OF THE CURATIVE ACTION OF ANTIPNEUMOCOCCUS SERUM.

An active antipneumococcus serum causes agglutination of pneumococci in vitro and in vivo. The antiserum acts in far greater dilution in causing agglutination as determined by the microscopic than by the macroscopic test. The antiserum when injected into the circulation of rabbits suffering from pneumococcus bacteremia causes a rapid disappearance of the diplococci from the blood. This disappearance is brought about by instantaneous clumping of the diplococci in vivo and the removal of the clumps by the liver, spleen, lungs, and possibly other organs.