524 IMMUNOLOGY 



Terplan reports the anatomical incidence of tuberculosis among 

 312 white children whose ages are between one month and six 

 years as 4 per cent; in 52 individuals ranging in age from seven 

 to eighteen years, it is 20 per cent; while for the age groups twenty 

 to forty and forty-one to eighty years, it is 60 and 95.7 per cent, 

 respectively. Terplan calls attention to the close agreement be- 

 tween the incidence of 20 per cent having tuberculous lesions de- 

 termined at autopsy for the age group seven to eighteen years and 

 the 20 to 25 per cent positive reactors to tuberculin (Mantoux 

 test) among the school children of Buffalo. It should be remem- 

 bered that the majority of the anatomical tuberculous lesions were 

 healed. In this study Terplan found some primary lesions in all 

 age groups. In discussing this report Long remarks that Terplan 

 has offered definite evidence that adults who escape primary tuber- 

 culosis infection in childhood are not likely to break down with 

 massive primary tuberculosis as was formerly thought to occur. 

 Apparently primary tuberculosis in adults tends to pursue a course 

 similar to that observed in children. 



Tissue Response to Various Fractions of the Tubercle Bacillus. 



— The effect on the allergic animal of various fractions of the 

 tubercle baciUus injected into the tissues has been studied exten- 

 sively by Sabin and her associates. They report that the phosphatid 

 fraction stimulates the formation of epithelioid and giant cells 

 while the acetone-soluble fat causes the proliferation of connective 

 1 issue and blood vessels and also causes hemorrhages. The waxlike 

 constituents stimulate fibroblast proliferation, and the carbohydrate 

 fraction is both chemotactic and toxic for leucocytes. When the 

 tubercular protein fraction is injected, both fever and the prolifera- 

 tion of plasma cells result. 



The Necessary Factors for the Development of Tuberculin 

 Allergy. — Wliile one can produce antilwdies for and render a 

 guinea pig anai^hylactic to tuberculin protein, it is interesting to 

 note that tuberculin hypersensitiveness or allergy as previously 

 described in this chapter does not result from the injection of 

 tuberculin OT or any of the others described by Koch (Baldwin, 

 1910, Fleischner, Meyer and Shaw, 1919, Zinsser, 1931). The 

 necessary factor for its production is the formation of a tubercle 

 containing living or dead tubercle bacilli or a tuberculin that 

 is antigenic; e.g., MA-100 within the tissues of a susceptible 



