ANTISERA 



PREPARATION OF ANTISERA— INDICATIONS FOR THERA- 

 PEUTIC USE OF ANTISERA 



Therapeutic antisera for protective and cui^ative 

 passive immunization fall into two general classes: 

 (a) antitoxic sera, and (b) antibacterial sera, accord- 

 ing to the mode of action of the bacteria against which 

 they are directed. 



Antitoxic sera are sera which are applied to the 

 group of bacteria whose deleterious action depends 

 upon the toxins separated from them in the process of 

 growth. The best examples of this class of bacteria 

 are the bacillus of diphtheria and the bacillus of 

 tetanus. 



Antibacterial sera are employed particularly in in- 

 fections by those bacteria whose toxins are contained 

 within the bacterial protoplasm (endotoxins). They 

 act by destroying the bacteria themselves. Generally 

 speaking, passive immunization has not been so suc- 

 cessful in dealing with infections by bacteria belong- 

 ing to this group, as with those whose action depends 

 on separated or extracellular toxins. 



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