522 VIBRIO 



absorption of agglutinins tests he believes that the Inaba (original), Hikojima (middle), 

 and Ogawa (variant) strains of V. cholerce, which have been extensively used for' sero- 

 logical work in the East, behave as if their heat-stable O antigens had the general structure 

 AX, ABX, and BX. By means of precipitin tests carried out with sera prepared by the 

 inoculation of rabbits with polysaccharide extracts, he finds that there are at least four 



receptor groups on the smooth polysaccharide of the cholera vibrio. Both the Inaba 

 and the Ogawa strains possess these four groups, two of which are type specific and two 

 of which are common to both types. In each type one of the receptors is alkali-labile 

 and the other alkaU-stable. 



White (1934a, 19356) has described the occurrence of alcohol-soluble protein antigens, 

 which he refers to as Q antigens. There is reason to beUeve that these substances play 

 a part in the non-specific O agglutination of boiled vibrios, described by Gardner and 

 Venkatraman. 



White's studies were interrupted by the war, but it may be worth while summarizing 

 his findings to date. From vibrio bodies he has isolated (1) a heat-labile protein antigen 

 (White 19406) ; (2) a heat-stable protein antigen, possibly associated with a hapten Cy2 

 (White 1940fZ) ; (3) an alcohol-soluble Q protein fraction ; (4) the differential S, R and 

 p antigens with their respective polysaccharide haptens Ca, C/? and Gd ; (5) another hapten 

 Cyl is probably also of somatic origin ; and (6) another, the "rugose " hapten (White 1940ffl), 

 has been derived from the intercellular secretion of rugose variant strains. Antibodies 

 for aU these components may occur in the sera of rabbits immunized with hving cultures 

 of V. cholerce. 



From this brief summary it will be apparent that the findings of Bruce White and 

 of Linton and his colleagues are by no means easy to interpret, and that much further 

 work will have to be done before the antigenic structure of even the cholera vibrio can 

 be expressed in chemical terms. For a review of the chemistry and antigenic structure 

 of the vibrios, see Linton (1940). 



Pathogenicity. — The cholera vibrio causes Asiatic cholera in man. Metchnikoff's 

 vibrio apparently is responsible for a choleraic disease in chickens (Gamaleia 1888a) 

 — not for true chicken cholera, which is due to a member of the Pasteurella group. 

 It is possible that F. pkosphorescens may cause acute gastro-enteritis in man, but 

 this has not been proved conclusively (Jermoljewa 1926). 



A disease simulating cholera may be reproduced in guinea-pigs and new-born 

 rabbits by certain experimental procedures (see Chapter 63). The cholera 

 vibrio when given by mouth, or injected per rectum, is harmless to mice, rabbits, 

 guinea-pigs, and monkeys. Intraperitoneal injection into guinea-pigs is fatal 

 within 24 hours. If a small dose of vibrios — J loopful of an 18-hours' agar 

 culture — is given, the animal dies of toxaemia, and at necropsy the peritoneal 

 cavity is sterile. If a larger dose is given, | loopful, cultures from the peritoneal 

 cavity may be positive ; and if a still larger dose is given, 1 or more loopfuls, the 

 vibrios may be recovered also from the heart blood. Intraperitoneal injection of 

 mice is fatal in 24 to 48 hours. Intravenous injection of young rabbits is fatal in 



1 to 5 days. According to Botman (see van Loghem 1938) the rat is comparatively 

 unaffected by the intraperitoneal inoculation of killed cholera vibrios, whereas it 

 is susceptible to El Tor vibrios. 



Metchnikoff's vibrio is more invasive than the cholera vibrio. Even after a 

 small dose given intraperitoneally to guinea-pigs, the vibrios can be recovered 

 from the heart's blood. It is fatal to guinea-pigs even when given subcutaneously ; 

 under these conditions the cholera vibrio gives rise merely to a local abscess. Both 

 guinea-pigs and chickens can be infected by feeding with V. metchnikovi. Moreover 

 this organism is pathogenic to pigeons, on intramuscular injection, while the cholera 



