This note is a report of studies undertaken with a view of determining whether specific proteolysins are produced in animals on protein injections, if a procedure simulating the production of specific haemolysins be adhered to.
The question of the presence of specific proteolytic substances in the blood of animals injected with proteins, is an old one and no attempt will be made here to go over the range of literature. Suffice it to recall that the so-called Abderhalden reaction for cancer and pregnancy, which was based on the assumption of the presence of such proteolysins in the blood (2), is now discarded. More recently, Taylor and Hulton (1) also, studied this problem from a biochemical viewpoint. They injected various proteins into rabbits with a view of detecting the presence of proteolytic ferments in the blood of these animals, obtaining negative results.