108 LABORATORY COURSE IN SERUM STUDY 



MATERIALS 

 Each student needs : 

 3.0 c.c. Antihuman serum (1-5). 

 1.0 c.c. Human serum (1-5). 

 4.0 c.c. Guinea pig serum (1-10). 

 4.0 c.c. Sheep cells (1-20). 

 0.5 c.c. Dog, cat, horse or sheep serum (1-5). 

 15 units antisheep-cell amboceptor. 



Salt solution. 

 10 one-c.c. pipettes. 

 15 half-inch test tubes. 

 1 test tube rack. 



LESSON XVIII 

 FORENSIC COMPLEMENT FIXATION 



THE fixation of complement by the specific action of a protein 

 and the serum of an animal immunized against it, is the basis 

 of a forensic test for the identification of blood stains and also for 

 the recognition of meats placed upon the market (for instance, 

 the detection of horse meat in sausages). 



Since the injection of the protein from any organ or tissue of 

 an animal results in antibodies which react with extracts from 

 any other tissue of the identical species (i.e., antibodies which are 

 race-specific and only to a slight degree organ-specific), it is 

 not necessary to produce the antiserum for the detection of meat 

 by injection of meat extract. The injection of serum or of blood 

 of the same species gives quite as useful antibodies and is much 

 more convenient. 



For the preparation of extracts from meat Seiffert recommends 

 the infusion of 30 grams of finely chopped meat in 30 c.c. salt 

 solution ; the mixture is to stand for 12 hours in the cold, and is 

 then filtered through a hard paper. Students prepare extracts 

 of two types of meat given out, 1 extracting 5 grams of chopped 



1 One of these should if possible be horse meat which can usually be ob- 

 tained from a board of health or a veterinary institution. The antihorse serum 

 is prepared in advance by the injection of three rabbits with horse serum. 

 (Lesson I.) If it is not possible to obtain horse flesh, the whole experiment can 

 be done with antisheep serum and mutton obtained from a butcher. 



