HOST RESPONSE TO ANTIGENIC ACTION 461 



toxin in determining susceptibility or resistance to infection stimu- 

 lated interest in a similar application of pneumococcal antigens. 

 Weil (1916) 1507 employed a saline autolysate of Pneumococcus 

 (usually of Type I) and injected the material intracutaneously in 

 the scapular region. The injection was immediately followed at 

 times in pneumonia patients, and in normal subjects as well, by a 

 superficial, ill-defined, cutaneous blush. If the superficial erythema 

 faded within a few hours, the reaction was considered to be nega- 

 tive. If, however, within twenty-four hours there occurred a well- 

 circumscribed area of erythema, with infiltration and papular 

 elevation of the skin surrounding the point of puncture persisting 

 for twenty-four hours or more, the reaction was called positive. 

 During the course of pneumonia, Weil found the reaction to be 

 negative, but twenty-four hours to two weeks after crisis a con- 

 siderable proportion of patients reacted positively. Normal indi- 

 viduals and subjects suffering from diseases due to organisms 

 other than Pneumococcus might or might not exhibit a reaction. 

 Analogous results were reported by Steinfeld and Kolmer 

 (1917), 1315 who employed saline suspensions of washed organisms 

 of Types I, II, and III heated to 60°. A positive reaction consisted 

 in a definite papule with an area of erythema greater than one 

 centimeter in diameter accompanied by slight edema. Positive re- 

 actions were observed in 30 per cent of patients suffering from 

 lobar pneumonia, but consistently negative results were obtained 

 with normal individuals and with those afflicted with various 

 chronic diseases. All positive reactions noted occurred after crisis 

 or after infection had persisted for a long period of time. Stein- 

 feld and Kolmer stated that there was no constant relation be- 

 tween reactions to the protein of the various types of pneumococci 

 used and the types found in the sputum. Weiss and Kolmer 

 (1918) 1510 employed as antigen hemolytic toxin prepared by dis- 

 solving washed, living pneumococci in sodium choleate. Among 

 adult patients with lobar pneumonia the intracutaneous reaction 

 was elicited as early as the fifth and as late as the thirteenth day 



