STUDIES ON ANTIBLASTIC IMMUNITY

Antipneumococcus serum under certain conditions apparently inhibits or retards the metabolic activities of the homologous pneumococcus. Antipneumococcus serum exhausted of its agglutinin content possesses no inhibitory properties. The degree of inhibitory action of antipneumococcus serum parallels its agglutinating power. No evidence has been found to indicate that the inhibition of the metabolic activities of the pneumococcus by antipneumococcus serum is due to a specific antienzymotic property of the serum. The evidence which has been obtained indicates that the apparent inhibition of metabolic activity that occurs under certain conditions is due to agglutination of the pneumococci by the antipneumococcus serum and their consequent inability to grow in intimate contact with the whole medium. Antistaphylococcus serum inhibits the liquefaction of gelatin and the formation of pigment by Staphylococcus pyogenes aureus. Further experimentation is necessary to determine the mechanism of this inhibitory action. Antistaphylococcus serum does not inhibit those metabolic activities of Staphylococcus pyogenes aureus essential to the growth and multiplication of the organisms.