552 INFECTION AND IMMUNITY. 



extent, of the conjunctiva, where the meningococ- 

 cus and the Micro coccus catarrhalis may be en- 

 countered. 



Phagocytosis. In the purulent stage of a gonorrheal infection 

 the cocci are found almost entirely within the leu- 

 cocytes, whereas in earlier stages, when the dis- 

 charge is slight and of a mucous character, and 

 also during convalescence, when the secretion 

 again becomes mucous, they are largely extracel- 

 lular. They are never within the nuclei. The 

 process is one of active phagocytosis in which the 

 cocci play a passive role. They occur not only on 

 the surface of the epithelium, but penetrate be- 

 tween and beneath the epithelial cells, and even 

 into the adjacent connective tissue. 

 Cultivation In culture media growth is slow and scant, and 



and Resist- , . ITT n i 



cultures rarely live longer than one or two weeks, 

 unless they are transplanted to suitable fresh media. 

 On the latter they may be carried through many 

 generations without losing their virulence. When 

 dried they die very quickly, but may live for some 

 hours on linen (towels) or the skin, and for 

 twenty-four hours in warm water. They are very 

 susceptible to temperatures above 42 or 43 C. 

 and show very little resistance to antiseptics, par- 

 ticularly the silver salts. 



The gonococcus secretes no soluble toxin, but 

 contains an endotoxin or toxic "protein" which 

 causes local and general symptoms in both man 

 and animals. Dead cultures produce an inflamma- 

 tory exudate in the peritoneal cavity of guinea- 

 pigs and mice, resulting in death if the dose is 

 sufficiently large, and when injected into the 

 urethra of man a temporary inflammation results. 

 An actual infection of any sort can not be pro- 



ance. 



