242 ANTITOXINS 



PRODUCTION OF POLLEN ANTITOXIN 



The pollen of certain plants is markedly toxic for susceptible in- 

 dividuals. In America the pollen of the golden-rod and of rag weed 

 frequently produce a syndrome of distressing symptoms known as 

 " autumnal catarrh." The onset and character of the symptoms of 

 pollen intoxication are strongly suggestive of an anaphylactic reaction. 

 Dunbar has studied pollen toxins quite extensively, and considers them 

 the etiologic factor in the production of hay-fever. 



Pollen antitoxin has been prepared by immunizing susceptible horses, 

 the toxin being isolated by mixing the ground pollen with 5 per cent, 

 sodium chlorid solution and 0.5 per cent, phenol at 37 C. for ten hours. 

 In the form of a proteid, it is then precipitated by adding eight to ten 

 volumes of 96 per cent, alcohol, dissolving the resultant white precipi- 

 tate in physiologic salt solution (Citron). 



THE MEASURE OF ANTITOXINS 



Antitoxin Unit. A unit is the definite measure of antitoxin in any 

 serum or solution that will neutralize a certain amount of toxin. As pre- 

 viously stated, the United States Government has established a definite 

 unit for the standardization of diphtheria and tetanus antitoxins, and 

 frequently examines the serums made by various licensed manufacturers. 

 Officers of the Public Health and Marine-Hospital Service purchase 

 from reliable pharmacists several grades of antitoxins made by each 

 manufacturer, which are then sent to the Hygienic Laboratory at Wash- 

 ington, where they are tested for potency, freedom from contamination 

 by bacteria, chemical poisons, especially tetanus toxin, and for excessive 

 amounts of preservative. Delinquencies are reported immediately, and 

 steps are taken to withdraw that particular lot of serum from the market. 



A unit of diphtheria antitoxin may be defined as the li amount of anti- 

 toxin that will just neutralize 100 minimal fatal doses of toxin for a 250- 

 gram guinea-pig." 



A unit of tetanus antitoxin may be defined as the "amount of antitoxin 

 which will just neutralize 1000 minimal fatal doses of toxin for a 350- 

 gram guinea-pig." 



The standardization of these serums is useful as a guide to their ad- 

 ministration, especially when given for prophylactic purposes, where 

 experience has taught that so many units usually confer protection; it 

 also serves for purposes of record. In the treatment of diphtheria and 



