﻿420 STRONG. 



high bactericidal serum by the injection of the prophylactic just described. 

 However, the question arises whether such a serum in man really repre- 

 sents an immunity against the disease Asiatic cholera — that is, does it 

 protect the individual against intestinal infection? This question ap- 

 parently resolves itself chiefly into one as to whether the organisms which 

 give rise to the symptoms of the disease actually come into contact with 

 the fluids of the body. 



All articles upon the pathologic histology of cholera agree that the 

 spirilla are found in the superficial layers of epithelial cells of the 

 mucosa, and, sometimes in large numbers, penetrate well into the sub- 

 mucous lining. Exfoliation of the epithelium is almost a constant 

 occurrence in severe infections, and in cases of longer standing the 

 organisms are sometimes encountered in large numbers at the bases 

 of erosions or ulcerations which have resulted in the large intestine. 

 In addition, the mucosa is usually distinctly cedematous, and there ob- 

 viously is no doubt but that the bacteria in any of these situations would 

 come into contact with whatever immunizing substances might exist 

 in the blood serum, and if bactericidal substances were present in suffi- 

 cient strength, the bacteria would be destroyed. However, we know that 

 very large numbers of the cholera spirilla remain in the lumen of the 

 intestine in the rice-water discharges and do not invade the intestinal 

 coats. We do not know whether these organisms which so remain in 

 the bowel give rise to the symptoms of the disease, since satisfactory 

 evidence that the cholera spirillum produces a soluble toxin has not yet 

 been presented; but even granting for the moment that they do, then 

 what influence if any would bactericidal substances in the blood serum 

 exert upon them? We are aware that one of the most common and 

 striking findings at post-mortem examinations in Asiatic cholera is the 

 so-called "rice-water" contents of the small intestine. The characteristics 

 of the rice-water stool are due to the flakes of mucus and the epithelial 

 cells which appear in suspension in the liquid contents. If we examine 

 these floccules of mucus bacteriologically we find that the spirilla are 

 usually most abundant in them, sometimes in almost pure culture. 

 However, this mucus is largely a secretion of the epithelial cells of 

 the intestine, although it is usually also mixed with a certain amount of 

 serum and such a secretion will probably possess the same bactericidal 

 substances as the blood serum itself, just as the sweat, the tears, and 

 the milk of immunized individuals contain these antibodies. Indeed, 

 it seems very probable that the intestinal epithelial cells which give 

 rise to the mucus are perhaps particularly able to produce these immuniz- 

 ing substances, since there is probably a special affinity or combining 

 power between these cells and the cholera organism, which is demon- 

 strated by the production of toxic substances in far greater amount in 



