438 BIOLOGY OF PNEUMOCOCCUS 



cocci with the serum, as recommended by Lamar, Strouse experi- 

 enced no difficulty in obtaining phagocytosis. 



Eggers (1912), 349 by the plate method of determining bacteri- 

 cidal action, found increased antipneumococcal properties devel- 

 oping in the serum of pneumonia patients at or shortly after crisis 

 and lasting for variable periods thereafter. Cases in which the 

 apparently characteristic increase of bactericidal power did not 

 occur presented irregularities either in course or in termination. 

 Dochez (1912) 315 was successful in proving the presence of sub- 

 stances protective for mice in the serum of patients ill with lobar 

 pneumonia. All but one of the serums tested showed the ability to 

 protect, the reactive substance appearing in only a few instances 

 before the time of crisis, while in some other cases the protective 

 power appeared to persist as long as the patient was under obser- 

 vation. In some patients, protective antibodies either became evi- 

 dent at some time after crisis or could not be demonstrated at any 

 period of the disease. Dochez concluded that the appearance of 

 specific protective substances in the serum of patients ill with 

 lobar pneumonia suggested that these bodies might play a part in 

 the mechanism of recovery. 



In the next year, Clough 240 reported the demonstration of 

 protective antibodies, specific for the infecting strain of Pneumo- 

 coccus, in the serum of the majority of patients after crisis or ly- 

 sis. Phagocytic activity of the serum ran closely parallel with pro- 

 tective power for mice. In addition to protective antibodies and 

 opsonins, Lacy and Hartmann (1918) 770 reported that specific 

 agglutinins usually appeared in the serum of pneumonia patients 

 during or shortly after defervescence. In a second report, Clough 

 (1919) 242 stated that the serum of 85 per cent of the patients ill 

 with acute lobar pneumonia whom he had studied showed positive 

 phagocytic activity after crisis or lysis, and that the serum of 79 

 per cent of the cases showed agglutinative activity. In a few in- 

 stances, positive results were obtained twenty-four hours or less 



