r.AOTi'nnoiuAL substances in fibrin. 175 



After one and one-half hours at room temperature no ]i£emol3fsis liaviug 

 occurred in any of the tubes, all of them were centrifugalized and the 

 fluid poured off. To each of the tubes were then added 1/10 cubic 

 centimeter of normal rabbit serum and 1 cubic centimeter of physiological 

 salt solution. After two hours at 37° C. and twenty hours at room 

 temperature, in series A complete solution had taken place in the tube 

 containing 4/10 cubic centimeter of fibrin extract; 2/10 cubic centimeter 

 had produced strong solution, 1/10 cubic centimeter none. In series B 

 complete solution had been produced by 1/lGO and 1/320 cubic centimeter 

 of serum, almost complete solution by 1/640 cubic centimeter, and very 

 strong sok;tion by 1/1280 cubic centimeter of serum. 



The entire amount of fibrin, therefore, in 50 cubic centimeters of the 

 blood of rabbit No. 21 had yielded a quantity of hagmolytic immune-body 

 equivalent to that possessed by 1/25 cubic centimeter of the same animal's 

 serum. 



Tlwrnugglutinins hi fibrin. — Rabbit No. 11 was given the washed 

 corpuscles of 10 cubic centimeters of chicken's blood into the ear-vein 

 and ten days later was bled from the jugular vein; for the following 

 experiment the fibrin from 30 cubic centimeters of the blood was obtained 

 by whipping. For the extraction, which lasted twenty-four hours, 10 

 cubic centimeters of salt solution were used. 



It was found that whereas 1/20 cubic centimter of the inactivated 

 serum produced comj^lete agglutination of 1 cubic centimeter of a 5 per 

 cent suspension of chicken's blood corpuscles, it required 1.6 cubic centi- 

 meters of the extract to agglutinate completely 1 cubic centimeter of 

 the same suspension, while 0.8 cubic centimeter agglutinated slightly and 

 0.4 cubic centimeter not at all. 



Therefore the amount of agglutinins available in the fibrin from 30 

 cubic centimeters of this blood equaled that found in about 1/3 cubic 

 centimeter of the same animal's blood-serum. 



These experiments and others of the same nature were often repeated 

 and always with the same result, namely, that there is an incomparably 

 greater quantity of the substances under consideration in the serum 

 than in the fibrin of the same specimen of blood. Consequently, the 

 logical conclusion of this study is, that if the benefit derived from fibrin 

 injections is dependent upon the classes of substances under investigation, 

 it must be considerably more advantageous to use the corresponding 

 sera for the purpose of treatment. However, when we remember how 

 unsatisfactory, as yet, the treatment has been with antistreptococcic and 

 antistaphylococcic sera, and it is the microorganisms with which these 

 sera are prepared which are chiefly responsible for the local inflam- 

 mations, it becomes apparent that if the injected fibrin does prove to 

 be efficacious in the cases mentioned, it will not be because it carries 

 bactericidal substances. 



86321 3 



