HOST RESPONSE TO ANTIGENIC ACTION 465 



tive or rarely positive in infants, infrequently positive in child- 

 hood, and positive in a high percentage of adults. 



Finland and Dowling (1935) 442 performed skin tests on pa- 

 tients recovering from lobar pneumonia and also on normal indi- 

 viduals and persons suffering from non-pneumococcal affections. 

 The antigens employed were the capsular polysaccharides of pneu- 

 mococci of Types I, II, and III, and the cellular carbohydrate of 

 Wadsworth and Brown. Immediate cutaneous reactions, similar 

 to those described by Tillett and Francis, were elicited in patients 

 recovering from pneumonia. These reactions were, in general, 

 type-specific and were associated with the homologous antibody in 

 the serum. Similar reactions were obtained with preparations of 

 soluble specific substance and cellular carbohydrate prepared from 

 the same pneumococcal types by the methods of Heidelberger, 

 Goebel, and Avery and those of Wadsworth and Brown, respec- 

 tively. 



Characteristic delayed reactions were seen only with the cellu- 

 lar carbohydrate and were not associated with type-specific anti- 

 bodies. The delayed reactions were most frequently observed fol- 

 lowing the injection of the cellular carbohydrate of the atypical 

 Type I Pneumococcus and of the analogous antigen prepared 

 from the virulent Type I strain. Delayed cutaneous reactions to 

 the cellular carbohydrate of an atypical Type I Pneumococcus 

 were obtained regularly during the febrile stage of a variety of 

 infectious diseases but could not be evoked soon after recovery in 

 these cases. The results are similar to those obtained by Francis 

 and Abernethy 475 with the somatic C Fraction of Tillett and 

 Francis. 



Among the non-pneumonic subjects on whom observations were 

 made, immediate reactions in general were uncommon. They oc- 

 curred most frequently with the cellular carbohydrates of Type I 

 and atypical Type I pneumococci. Delayed reactions with soluble 

 specific substance of any type did not occur, but they were fre- 



