238 



INFECTION AND RESISTANCE 



TABLE FOR ISO-AGGLUTININS * 



Sera 



* For this table as well as for much direct information concerning the iso-agglutinins and iso- 

 lysin we are indebted to Dr. Ottenberg of this laboratory. 



cal of the first, the serum having no agglutinin, the cells being ag- 

 glutinated by the serum of any other group. (See table.) It is 

 evident from examining this grouping that the phenomena can be 

 explained (as Landsteiner has suggested) if it is assumed that there 

 are two agglutinins (a and ft) and two corresponding agglutinogens 

 present in the red cells (A and B). The blood of the first group pos- 

 sesses both agglutinins, but no agglutinogens, the blood of the second 

 group possesses agglutinin a ? agglutinogen B, the blood of the third 

 group possesses agglutinin /?, agglutinogen A, the blood of the fourth 

 group possesses no agglutinin but both agglutinogens. 



These agglutinins are present in weak dilution only, being gen- 

 erally active in dilutions only of 1-15 to 1-30. They are separately 

 absorbed from the serum by the suitable red cells (Hektoen). 55 Ot- 

 55 Hektoen. Jour, of Inf. Dis. } 1907, p. 297. 



