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Mr. L. S. Dudgeon. On the Presence of [Feb. 18, 



Hcem-agglviinins in Normal Blood. 



Attention has already been drawn to a statement made in the preliminary 

 communication on this subject. Since then a wide study of hsem-agglutinins 

 in normal blood has been made. It has now been proved that although a 

 certain sample of normal serum may fail to react with one or two specimens 

 of washed normal red cells, yet, if sufficient examples of normal red blood 

 cells are presented to that specimen of normal serum, agglutination will be 

 found to occur in a certain proportion of instances, while some samples of 

 normal serum agglutinate most specimens of normal red cells presented to 

 them. With our wider knowledge we can state that auto-agglutination does 

 not occur, and that the htemolytic agglutinins have not met with, that type 

 of agglutination which is of such interest in typhoid and certain other 

 infections. These results are important because they compel one to realise 

 that the demonstration of mem-agglutination is not necessarily a reaction 

 of pathological significance. 



Auto-agglutination. 



A negro from the West Indies, who had not been out of England for over 

 ten years, showed a blood possessing remarkable properties. He was 

 considered to be a ease of tertiary hepatic syphilis. When blood escaped 

 from his tissues from a single puncture, the red cells could be seen to be 

 clumped in the plasma, and when the bleeding was continued into citrated 

 saline the red cells fell to the bottom of the tube in enormous clumps. This 

 is the only instance met with of a blood showing spontaneous agglutination, 

 and auto-agglutination of such a high degree. In the preliminary com- 

 munication, attention was called to the condition of the blood in a case of 

 long standing epilepsy : here well-marked auto-agglutination was present, but 

 not spontaneous agglutination, and the degree of agglutination was nothing 

 like to the same extent as was obtained with the blood of the negro. On 

 the addition of the immune serum to normal red cells a high degree of 

 agglutination occurred, and it was the true hemolytic type. 



It had previously been shown that if an immune serum is diluted with 

 normal saline, it rapidly loses its power of agglutinating red cells, quite out 

 of proportion to what is observed in the case of the bacterial agglutinins. 

 This sample of immune serum, however, clumped normal red cells when 

 diluted to the extent of 1 in 10 almost as well as the undiluted serum, and 

 some clumping occurred in a dilution of 1 in 500. This is the only instance 

 out of the whole series of sera which have been examined in which such 

 a phenomenon was noted. When the negro's blood was examined about 



