98 



Tlie vaiiouw liaemolytic tests of the serum from the infused animals 

 were made o]i the corpuscles of live horses and five mules. Whilst 

 from the horses, mules, and donkeys, treated subcutaneously with blood 

 and serum, all gave rise to isolysines in their serum, there were 

 amongst the infused horses only o7'5 per cent., amongst the infused 

 mules J:,S'5 per cent., with isolytic serum. The transfusion i^roved to be 

 the best method of hyperimmunisation against horse-sickness, hence it 

 was chosen for the future. 



The majority of the sera of the various horses infused with horse 

 blood, and mules with mule blood, was more liaemolytic lor horses than 

 for mules. 



There were a greater number of mule sera more liaemolytic for 

 mule than tor horse blood corpuscles. 



The question ai'ises whether the greater liaemolytic index of the 

 majority of horse and mule sera fcjr horse than for mule blood is due to 

 a proiuinent sensibility of the horse erythrocN^tes or whether there are 

 in an isolytic serum two different isolysines for horse and mule blood. 

 If this latter should be the case the isolysines for horse blood would be 

 in excess. 



The quantities of isolysines in the various horses and mules after 

 immunising by subcutaneous injection or infusion are quite different. 

 There again seems to be no I'elation between the number of injections, 

 the quantity injected or the number and amount of bleedings and the 

 liaemolytic potence of the serum. 



One would think that the individual properties of the blood used 

 for ijijection or infusion have an influence on the quantity of the 

 produced haemolysines : but it was not possible to find any cj[uantitative 

 similarly in the liaemolytic action of the sera of those animals which 

 were injected with the same blood. We must therefore consider that 

 the main factor ruling the quantity (and quality) of the isolysines is the 

 individuality of the injected animal. 



Temxierature reaction of an animal after hyjperimmunisation would 

 be an expression of its sensibility ; it has to be taken into considera- 

 tion that the degree of hyperthermia might be an indicator for the 

 production of antibodies, in our case isolysines. Indeed, it was found 

 that the majority of animals showing a temperature reaction after in- 

 fusion and the minority of those not reacting contained isolysines in 

 their blood : but at the same time a considerable number of sera derived 

 from lioises or mules showing thermo reaction was not liaemolytic, 

 whilst some of those without rise in temi)erature was haemolj'tic. 



These facts proved that fever reaction after hyperimmunisation is 

 not always a sign of the production of antiliodies and that immune 

 substances also arise, though no alteration of temperature followed the 

 injections. 



