PRACTICAL APPLICATIONS OF METHOD 215 



that the inactivation of the tumor sera greatly diminishes their spe- 

 cific fixation properties, and for this reason he at first advised that 

 the serum be used unheated. He has found recently that the best 

 results are obtained when the serum is heated to 54 C., together with 

 a little sodium hydrate solution. He handles the blood in the fol- 

 lowing way: After being taken from the patient it is allowed to 

 stand 1 to 2 days in the refrigerator ; just before use he adds two parts 

 of an -^5- KaOH solution with one part, of serum* and heats it for half 

 an hour at 54 C. As it is important that the sodium hydrate should 

 contain no sodium carbonate, he advises the .use of the Kahlbaum 

 preparation. In setting up the test he uses graded .quantities of the 

 mixture corresponding to 0.2, 0.1, 0.05, and 0.025 c. c. of the original 

 serum. To each of these quantities he adds the stated quantity, 0.8 

 c. c. antigen preparation described above, and the 0.05 guinea pig 

 complement. Controls must be set up with the antigen alone and 

 with the patient's serum alone to prevent error from independent 

 fixation by these substances. These reactions are allowed to stand 

 three hours at room temperature, and then one cubic centimeter of 

 a 5 per cent, solution of beef blood sensitized with two units of hemo- 

 lytic serum is added (as in the Wassermann reaction). It is im- 

 portant to use a strongly sensitizing serum,'' so that not too nmch of 

 the hemolytic rabbit serum must be added to the tubes. ^Experi- 

 ments done in this way with normal sera usually result in complete 

 hemolysis within one hour, although in certain other diseases, i. e., 

 tuberculosis and syphilis, slight inhibition may result. However, 

 fixation with the patient's serum in quantities of 0.1 c. c. or less is, ac- 

 cording to von Dungern, fairly specific for malignant tumors, since 

 normal sera treated in the way described usually do not cause fixa- 

 tion in quantities of less than 0.2 c. c. and, in syphilis and tubercu- 

 losis, if fixation is at all present, it is usually not evident in quanti- 

 ties less than 0.1 c. c. 



With a reaction so carried out 'von Dungern has examined 244 

 cases. The following tabulation states his results: 



* Taken from von Dungern, "Weichhardt's Jahresbericht," Vol. 8, 1912, p. 174. 



