512 INFECTION AND IMMUNITY, 



them on a good basis, although some favorable re- 

 ports have been given. 



serum of The serum of Eoemer is obtained by immuniz- 

 ing different kinds of animals with several strains 

 of pneumococci. The receptor apparatus of differ- 

 ent strains probably differ ; hence, a serum obtained 

 by immunization with several strains probably 

 would be effective against a large variety of pneu- 

 mococci. Furthermore, since different animals 

 may respond to immunization with a given organ- 

 ism by the formation of amboceptors with different 

 complementophilous haptophores, a theoretical ad- 

 vantage is to be gained by mixing immune serums 

 from several animals. The amboceptors of one or 

 more of the serums may be susceptible to activa- 

 tion by the complement of the patient's body, 

 whereas if only one serum were used the chance of 

 such activation would be decreased. Passler, in 

 summing up the results obtained in the treatment 

 of 24 cases with this serum, finds the course of the 

 disease shortened, the temperature reduced and a 

 tendency to limit the extension of the disease to 

 other parts of the lungs. According to Neufeld 

 and Haendel the disadvantage of the various anti- 

 serums lies in the fact that they cannot readily be 

 given in large enough doses to be effective. 



The serum of pneumonia patients shows an in- 

 ation. crease( j agglutinating power for the pneumococcus. 

 The maximum is reached at or near the time of 

 crisis, but rarely has a higher value than 1 to 50 

 to 1 to 60 (Neufeld, Eosenow). It disappears 

 quickly after recovery. In immunized animals the 

 agglutinating power may be pushed to much higher 

 limits. Not all strains yield agglutinins equally, 

 and not all are agglutinated equally by the same 



