334 LOCAL TISSUE REACTIVITY 



may react willi llic aiitii2,c'n injected intraxenously tAveiity-foiir 

 hours later, the complex ol the antigen ^vith the locally lormed 

 aiiliboclies bcin," resj)()iisil)le for the local reaction follo\viiig the 

 intravenous injection. It is, however, readily seen that the ex- 

 perimental e\idence cannot substantiate this hypothesis. 



As already mentioned, skin-preparatory and reacting factors of 

 various biologically and serologically tmrelated microorganisms 

 are alole to substitute for one another pro\ ided they have the 

 power of eliciting the phenomenon for themsehes. 



In the basic experiments described in the introduction, the 

 combined injections of B. typlwsus, meningococcus and B. coli 

 culture filtrates ^vere successfully used. In later experiments, the 

 phenomenon to streptococcus was reproduced by the combined 

 intradermal injection of B. typliosiis or meningococcus "agar 

 washings" filtrates with the intravenous injection of streptococcus 

 cultures or streptococcus cultine filtrates. Combinations of me- 

 ningococcus Avith pneimiococcus and also combinations of B. ty- 

 phosus with B. tuberculosis ctdture filtrates gave positive and 

 consistent results. 



Ecker and Welch (1930) elicited the phenomenon by com- 

 bined intradermal and intravenous injections of heterologous fil- 

 trates of B. typhosus, B. paratyphosus and B. coli cultiu^e, and 

 concluded that heterologous filtrates of the same group of or- 

 ganisms produce the phenomenon in some cases. In some rabbits 

 there was, however, a suggestion of serological group specificity 

 of the reaction. Stolyhwo (1935 and 1936) found that it is pos- 

 sible to produce the phenomenon by combined intradermal in- 

 travenous injections of B. typlwsus and B. paratyphosus culture 

 filtrates. He gained the impression that the employment of homol- 

 ogous skin-preparatory and reacting factors resulted in stronger 

 reactions than in the experiments in which the heterologous fil- 

 trates were employed. 



Burnet (1931) combined the injections of heterologous filtrates 

 derived from such ^videly different organisms as B. typhosus, B. 

 (lyseuteriae flexner, B. pertussis and meningococcus. Strong cross 

 reactions were produced with these materials and in well con- 

 trolled experiments no evidence was obtained of any specificity. 

 According to Linton, Singh and Seal (1935) . combined injections 

 of filtrates obtained from various groups of J'ibrio cholerae are 

 able to elicit the phenomenon for each other. Plant (1932) Avas 

 able to produce the phenomenon by combined injections of 



