BLOOD RELATIONSHIP 323 



ing results following such treatment depend in part upon 

 the inappropriate character of the heterologous blood of 

 which the patient can make little use, and which places 

 him under the disadvantage of being compelled to dis- 

 solve and destroy all the formed elements as well as 

 to rid himself of the offensive proteins in the serum. 

 It has been found by experience that physiological salt 

 solution and Ringer's solution are more satisfactory in 

 that they fill the vessels, and enable the heart to con- 

 tinue its work until blood regeneration begins, without 

 introducing anything offensive into the body. But when 

 the corpuscles are essential, and the transfusion is practised 

 for the purpose of supplying the anemic patient with 

 them, human blood, and not heterologous blood, must be 

 employed. Under these circumstances, when the blood 

 of one healthy human being is introduced into the vessels 

 of another, it would seem as though invariable benefit 

 ought to accrue, but the result is riot always so satisfactory 

 as might be expected, because there are individual as well 

 as specific and racial differences, and the normal blood of 

 one human being may prove prejudicial to another. 



Thus, if the introduced corpuscles, instead of being per- 

 mitted to circulate like those normal to the patient, are 

 agglutinated or dissolved, no benefit can be derived from 

 their presence, and the patient may be injured through 

 the occurrence of fever, edema, hemoglobinuria, etc. 



That certain individuals are benefited and others in- 

 jured by human corpuscles vicariously supplied to them 

 has been shown through the researches of Landsteiner, 

 Shattuck, Hektoen, Ottenburg, Moss, Gay, Brem, Lee, 

 Karstner, and others to depend upon the presence or 

 absence in the blood of the recipient of factors called 

 isohemagglutinins and isohemolysins. 



If these factors are absent, the donated corpuscles are 

 uninjured and seem to be utilized as are those fabricated 

 by the patient himself; if they are present, the donated 

 corpuscles are attacked and destroyed. 



As the outcome of the investigations to which reference 

 has been made, human beings can be divided into four 



