BACTERIOLOGY IN A NUTSHELL. 



Work of 

 Antitoxin a 

 ^Chemical 

 Process. 



Phagocytic 

 Power. 



Bactericidal 

 Province of 

 Serum, 



as a result of injury to the phagocytes. Ehrlich 

 does not take up these points to any great 

 extent, but some of the supporters of his theory- 

 believe that complement exists normally in the 

 blood in the plasma. 



With regard to the action of antitoxins, 

 Metchnikoff affirms that antitoxin stimulates 

 the phagocytes to an increased absorption and 

 destruction of toxins, while Ehrlich holds 

 the opinion that antitoxin combines with toxin 

 by a chemical process only. Metchnikoff 

 believes that all types of immunity are depend- 

 ent, either directly or indirectly, on the activity 

 of phagocytes. Ehrlich's "side-chain" theory 

 does not coincide with this view, yet it does not 

 overlook the importance of phagocytosis in 

 certain infections. 



It has been demonstrated by scientists that 

 recovery from some of the communicable dis- 

 eases (for example, those due to the staphylo- 

 coccus, streptococcus, and pneumococcus infec- 

 tions) is not accompanied by marked antitoxic 

 or antibacterial properties in the serum of the 

 blood. On the contrary, an increase in the num- 

 ber of circulating leucocytes is found, which are 

 known to be cells of bactericidal or phagocytic 

 power. 



In certain other diseases, for example, 

 typhoid fever and diphtheria, just the opposite 

 condition is found. It would seem therefore, 

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