ALBUMINOLYSINS 105 



with trypsin, suggests the possibility, at least, that, even normally, 

 antiferment production occurs in the animal body and renders the 

 conclusion not unwarrantable that these antiferments are essential 

 to the life of the whole organism. 



Antilipoids (Lipoidophilic antibodies}. Still more recent studies 

 have brought to light another interesting class of antibodies which are 

 not "tuned" to any particular cell, so far as our present knowledge 

 goes, but which have the power of reacting with substances belonging 

 to the group of lipoids. Such antibodies have been discovered in 

 patients suffering from syphilis, yaws, frambesia, trypanosomiasis, 

 cancer, leprosy, etc., and may, for the present, be spoken of as 

 antilipoids or lipoidophilic antibodies. Their reaction with the 

 corresponding lipoids is characterized by the fact that if com- 

 plement be present at the time this is fixed to a greater or less 

 degree, so that upon the subsequent addition to the mixture of 

 lipoid, antilipoid, and complement, of washed red corpuscles and a 

 suitable hemolytic amboceptor, hemolysis either does not occur at 

 all, or is more or less impeded. This remarkable phenomenon is 

 the basis of the so-called Wassermann test for syphilis, and as such 

 constitutes one of the most important discoveries of medicine (see 

 Wassermann reaction). 



Albuminolysins. I have pointed out above that upon injecting 

 albumins, either of vegetable or animal origin, into an animal of an 

 alien species, antibodies are formed which are known as precipitins 

 and are characterized by their ability to form a precipitate, when 

 brought together with the corresponding antigenic substances. 

 The allergic state which develops as the result of the injection of 

 foreign albumins can manifest itself in still other ways, however. 

 If a guinea-pig is thus injected with normal horse serum, for example, 

 and an interval of from ten to thirteen days is allowed to elapse, it 

 will be noted that the second injection is followed by most alarm- 

 ing symptoms intense dyspnea and marked drop of tempera- 

 ture ( Theobald Smith phenomenon) which frequently end in death. 

 Corresponding symptoms occur in other animals and may follow 

 the introduction of almost any foreign albumin by parenteral chan- 

 nels. Evidently the first injection sensitizes the animal to, subse- 

 quent injections and the thought naturally suggests itself that here 

 also antibodies may play a role. What these antibodies are is still 

 a matter of surmise. Some investigators have attempted to identify 



