440 BIOLOGY OF PNEUMOCOCCUS 



such substances could be found at any time during the course of 

 the disease. In a second paper, Sia with Robertson and Woo 1273 

 reported that the same conditions prevailed in pneumonia caused 

 by pneumococci of Types I and II and Group IV. At the critical 

 period, opsonins and agglutinins were also demonstrable in the 

 blood. 



Other evidence of the production of an altered condition related 

 to the immune state developing in the body of pneumonia patients, 

 was the abolition of reactivity of the skin to pneumococcal fil- 

 trates and extracts, as described by Herrold and Traut (1927). 637 

 The serum of patients failing to react to the skin test partly or 

 completely neutralized in vitro the antigenic substance in the ac- 

 tive extracts and conferred protection upon mice. 



The time factor in the appearance of protective substances and 

 agglutinins in the course of lobar pneumonia was investigated by 

 Lord and Nesche (1929). 828 The authors were unable to find these 

 antibodies in the blood of patients before a fall in temperature by 

 crisis or lysis, but could demonstrate their appearance and con- 

 tinued presence as soon as defervescence took place. Lord and 

 Nesche attributed importance to the action of protective anti- 

 bodies in bringing about recovery, since a large proportion of 

 pneumonia patients with these substances in the blood conquered 

 the disease, while the majority of patients without protective anti- 

 bodies in their serum died. However, that immune bodies may be 

 present in the early stages of untreated pneumonia is indicated by 

 the experiments of Ward, 1480 who observed that the phagocytic 

 titer of whole human blood was comparatively high against the in- 

 fecting organism. For Ward, the fact pointed to a local rather 

 than a general lowering of resistance in infection with Pneumo- 

 coccus. 



In 1931, Lord and Persons, 838 continuing the study of the pro- 

 duction of specific antibodies during pneumococcal pneumonia, re- 

 ported that although in general the appearance of protective 

 substance coincided sharply with the fall in temperature of the pa- 



