.MICIIKiAN \( ADK.M^ Ol' SCIKNCK. 119 



DISTII.LKI) WATKH A N M* 1 1 V I.OTOX I N . 



W'c have bt'cii able to i)r()duci' aiiaplix loloxiii l>y tlic dilution of sira 

 with distilled water. Thus normal and sensitisicl rat scrum can be made 

 toxic. Normal rat serum diluted one to six ))roduc?s a relatively power- 

 ful anaphylotoxin when incubated 30 minutes at .'JS deorees (". Sensi- 

 tised rat serum, i. e., strum sensitised to e^<>; white when similarly treated, 

 becomes toxic witii five minutes' incubation. Here if any place one might 

 expect to find proteolysis. The results that have been obtained shows 

 a slight increase in the case of sensitised serum but the usual drop when 

 normal rat serum was made anaphylotoxic by dilution with distilled 

 water. 



INULIN. 



Nathan has siu)wn that the polysaccharide, inulin. produces anapiiylo- 

 toxin from normal guinea ])ig serum and tliat its ability to do so de])ends 

 upon its physical state. An inulin suspension produces the toxicity 

 readily while a solution of the same substance fails to initiate such 

 toxicity. A 5% suspension in .85% salt solution was used. The ex])eri- 

 ments were carried out in the usual manner on normal guinea pig serum 

 using as a control untreated serum. 



After 30 minutes' incubation at 38 degrees C. it was noted tliat the 

 toxicity was marked but did not at that time reach its maximum. Coinci- 

 dent with it was a slight increase in amino acids. At 90 minutes the 

 toxicity had reached its maximum but the amino-acid content actually 

 fell, in as great proportion as it had ])reviously increased. So. while 

 there is a primary increase in amino nitrogen it fails entirely to keep 

 pace with the intensity of toxicity. 



Similar experiments carried out on rat serum substantiate this result. 

 In every case no increase has been observed and is markedly less than 

 the control of normal untreated serum. 



Sensitive serum can be made anaphylotoxic by incubation of that serum 

 with its corresponding antigen. Using egg white as antigen one might 

 expect here if ever with an antigen capable of hydrolysis an increase in 

 amino acids if ))roteolysis were involved. Rabbit serum sensitised 

 against egg white was used and incubated with its antigen for various 

 lengths of time. Repeated attemjjts failed to demonstrate any increase 

 in amino acids accompanying toxification. The same was true when 

 guinea pig serum sensitised against egg white was used. Careful search 

 has failed to disclose a shred of evidence that would connect the diges- 

 tion serum proteins with the formation of anaphylotoxin. In two or 

 three instances slight increases in amino nitrogen has been detected at 

 times when tlu' scrum has been toxic. lint in each oi these instances 



