158 LO(^AL TISSUE REACTIVITY 



of peptone, althoiioh tlic injection o{ sodium chloride or honiol 

 ogoirs or heterologous seriun into the skin alter the j^reliniinary 

 intracutaneous serimi injection remained negative. According to 

 P. Bordet. the preliminary local serum injection increases the 

 skin sensiti\ity to the irritating properties of peptone and milk 

 \vhich cannot be manifested ^vhen injected into the unj)rej)ared 

 skin. The action of the previous serimi injection seems to him to 

 rest in the s^velling or thickening of the skin which it causes. 



The objection \vhich may be raised against liordet's obser\a- 

 tion is that a certain amoinit of bacterial toxic substances may be 

 present in the peptone and milk. Chapoteaiu's peptone is made 

 by the prolonged digestion of stomachs of pigs remoxed after 

 death. Milk, even Avhen drawn under the strictest ase])tic precau- 

 tions, contains \arious numbers and types of bacteria (V^ollum, 



19-^9) ■ 



Freinid (i9^54<'/) reports that when concentrated broth or tur- 

 pentine is introduced into the skin of tubercidous guinea pigs 

 and later typhoid hltrate is injected into the vascidar system, no 

 hemorrhages occtu" in the skin at the site of inflammation. 



Marginesu (1934) exposed the skin of rabbits to ultraviolet 

 radiation following the local congestion. An intravenous provoca- 

 tive injection of B. coli culture filtrate was made. No reactions 

 were obtained at the site of the radiated skin areas. 



The above author also used copper acetate as a skin-prepara- 

 tory agent xvithout success. It is interesting that copper acetate is 

 a strong vascidar poison capable of producing in rabbits exten- 

 sive vascular lesions of the internal organs. 



Freund reported that eel sertmi coidd serve as a skin-prepara- 

 tory agent. Michelazzi (ig'^r^d) , however, prepared the skin with 

 anti-rabbit hemolytic serum and eel serimi with negati\e results. 

 B. coli filtrate xvas used for the provocative injection. 



Fiorito (19-53) prepared the right ear of a rabbit 'with 0.05 c.c. 

 of a 10 per cent solution of turpentine and the left ear xvith an 

 active fjacterial filtrate. Twenty-four hours later, he injected Vib- 

 rio cholerae culture filtrate intravenously. Five rabbits shoxved 

 i-[- reactions and 5 rabbits gave no reactions in the turpentine 

 prepared skin sites. In the 5 rabbits xvhich were negati\e w'lXh 

 turpentine, the ears prepared with the bacterial filtrate showed 

 distinct reactions but of varying intensity. 



Sickles (1931, 1934) found that agar in the fbrm of Hitchen's 

 medium, possessed no skin-preparatory potency. In recent experi- 



