THE ACTION OF ANTITOXIC SERUM. 745 



on in the blood-stream, thus owe their ability to convert bacteria 

 and their toxins into harmless products to trypsin. 



THE PHYSIOLOGICAL ACTION OF ANTITOXIC SERUM. 



At the end of the previous chapter we stated that, judging 

 from the stage of our analysis then reached, antitoxin con- 

 tained blood-serum, alexins, trypsin, and oxidizing substance. 

 In the light of the data submitted in the foregoing pages, each 

 of the constituents of antitoxin seems to us to have acquired its 

 due position as a physio-chemical agency. 



The oxidizing substance, irrespective of its functions in the 

 blood-stream when it combines with the fibrinogen, subserves 

 all the other functions of the organism. Hence, the plasma 

 must contain and we have seen that it does a constant sup- 

 ply of oxidizing substance over and above that utilized in the 

 blood itself. The fibrinogen granules being supplied by leuco- 

 cytes, they are doubtless distributed in measured quantities, as 

 it were just enough to sustain the blood's normal temperature 

 or raise this if albuminoid poisons are present in the blood- 

 stream. The increase of oxidizing substance insured by the 

 adrenal overactivity which the poison itself causes compensates 

 for extra oxygen used under these circumstances. Still, leuco- 

 cytogenesis being commensurate with the surplus of adrenal 

 activity, it becomes evident that at least the greater part of 

 the oxidizing substance supplied to the blood-stream combines 

 with the excess of fibrinogen formed to liberate heat-energy. 

 It follows, therefore, that, while some oxidizing substance may 

 be present in antitoxin, it cannot be considered as a prominent 

 constituent of the substance. This does not prevent its dis- 

 ruptive influence upon toxics that are converted by oxidation 

 into harmless products. Indeed, we have seen that phagocytic 

 leucocytes absorb plasma, and with it oxidizing substance. As 

 it is these cells which carry drugs, poisons, etc., introduced in 

 the digestive canal, into the body itself, it is within their di- 

 gestive vacuole that the poison first meets its foe. If a bacillus 

 or an albuminoid: a toxin, a vegetable poison, etc., it is at- 

 tacked by the trypsin; if an oxidizable body, by the oxidizing 

 substance. 



Buchner's alexin has likewise suffered from the analysis 



