100 



THE PRINCIPLES OF IMMUNOLOGY 



Inasmuch as the Moss classification has been widely adopted we 

 include the chart of that system so as to show the relation of the 

 two systems of grouping : 



Moss CLASSIFICATION 



Sera 

 I. II. III. IV. 



I. 4- + + 



5 II. - + + 



HI. + + 



IV. 



It is of the utmost importance that when the groups are deter- 

 mined in any individual the method of classification should be 

 clearly stated. 



The incidence of the groups varies somewhat, according to the 

 figures of different investigators, and there is probably a factor of 

 error due to " random sampling," in spite of the large number of 

 individuals examined. Selected figures follow, according to the 



Jansky classification : 



Groups 



ii. 



in. 



IV. 



i. 



Von Dungern 

 Hirschfeld 



Moss 43. 



Olmstead . 

 Karsner . . . 

 Koeckert . 



Average 42.84 per cent. 41.38 per cent. 10.36 per cent. 5.42 per cent. 



The table shows that about four-fifths of all individuals fall in 

 Groups I and II, about equally divided between the two groups, the 

 next most frequent being Group III, and the least frequent being 

 Group IV. 



Characters of Iso-hemagglutinins. The iso-hemagglutinins are 

 neither filterable nor dialyzable, and are destroyed by heat of 62 to 

 66 C. for thirty minutes, depending on concentration, i.e., the agglu- 

 tinins in high dilutions (1-32, 1-64) disappear at 62 C., and in the 

 undiluted sera at 65 to 66 C. They are present in transudates and 

 exudates as well as in the plasma and serum, the serum showing a 

 greater concentration than the plasma. In serum the titer is usu- 

 ally between 1-16 and 1-32, although it may be as low at 1-2, and 

 has been reported as high as 1-320, irrespective of group. There is 

 variation of agglutinin content and probably of agglutinability of 

 cells at different times in the same individual. 



The fact that a blood contains an iso-agglutinin does not nec- 

 essarily mean that it will similarly dissolve corpuscles, but the 

 converse is true ; namely, that if a serum shows iso-hemolytic prop- 

 erties it is also iso-hemagglutinative ; the group relationship prevails 

 in both agglutination and hemolysis. In fact, agglutination always 

 precedes hemolysis. In spite of this generally accepted view, 

 Kolmer claims recently to have demonstrated the presence of iso- 

 hemolysins independent of iso-agglutinins. 



