PRODUCTION OF ANTIPNEUMOCOCCIC SERUM 547 



sputum now in general use, the former practice of administering a 

 dose of bivalent or polyvalent serum during the period required 

 for type diagnosis is no longer necessary. In view of present-day 

 knowledge, a logical and conservative procedure would be the pro- 

 duction of monovalent Type I serum, bivalent Type II and V, pos- 

 sibly a serum combining Type III and VIII antibody, and either 

 bivalent or polyvalent serums for other closely related types. 



METHODS OF CONCENTRATING SERUM 



The objectives of the processes employed in the concentration 

 and refinement of antipneumococcic serum are to eliminate non- 

 essential and harmful constituents and to reduce the volume of 

 fluid while conserving specific protective substances. In a study of 

 the distribution of immune bodies occurring in antipneumococcic 

 serum, Avery, 32 by chemical methods, demonstrated that the anti- 

 bodies in antipneumococcic serum are associated with the globu- 

 lins and not with the albumin fraction. Gay and Chickering 

 (1915), 508 9 and later Chickering (1915), 223 showed that the pre- 

 cipitate which forms when an extract of pneumococcal cells is 

 mixed with homologous antiserum contains practically all the im- 

 mune substances and that the antibodies can be recovered from the 

 precipitate in a water-clear solution by treatment with dilute al- 

 kali. By a similar method, Huntoon et ah (1921) 665 " 6 ' 668 precipi- 

 tated the specific antibody from antipneumococcic serum by treat- 

 ment with heavy suspensions of pneumococci. Various procedures 

 have since been utilized for the purpose of dissociating the antigen- 

 antibody complex so formed and of preparing for therapeutic use 

 solutions of the specific antibodies so released. 



Biological methods. The biological methods of concentration 

 employed by Gay and Chickering and by Huntoon are of interest 

 in establishing immunological principles. Although, as stated in 

 the Rockefeller Monograph, the products thus obtained were ideal 

 in many ways, there were serious disadvantages in the method. The 



