TETANUS TOXIN E. 125 



It had already been found by TIZZONI and CATTANI that it 

 was precipitated by magnesium sulphate. They had also observed 

 that the globulins that were precipitated by means of weak 

 acids (acetic acid, carbonic acid) or those separated by means of 

 dialysis did not carry down the antitoxine, but only those 

 globulins that were precipitated by means of solid magnesium 

 sulphate at 30 C. 



PICK (loc. cit.) was able to confirm these statements by means 

 of his more delicate methods. According to his results tetanus 

 antitoxine is distributed in exactly the same manner as diphtheria 

 antitoxine; thus, in horse serum, he found it to be combined 

 exclusively with the pseudoglobulin. 



The value of tetanus antitoxine has been calculated by 

 BEHRiNG 1 in the following manner : A "single" serum is taken 

 to be that which will protect 1 grm. of an animal against the 

 action of a certain lethal dose. Thus 1 c.c. of serum of the 

 strength of 1 in a million will protect 50,000 mice of 20 grms. 

 each ; hence a mouse requires ^^Jo^ c.c. or 0-00002 c.c., a sheep 

 of 50 kilos. 0-05 c.c., and a horse of 400 kilos. 04 c.c. Recently, 

 however, the serum has been tested as accurately as diphtheria 

 serum in the Royal Institute for the Investigation and Testing 

 of Serum. Test poisons are standardised upon a test serum that 

 has been kept unaltered, and are then used for the valuation of 

 the sera under examination. 



A fact of the greatest importance for the estimation of the 

 action of antitoxine in the organism was that established by 

 HANS MEYER and RANSOM (loc. cit.) viz., that the antitoxine, 

 unlike the toxine, is not capable of penetrating the axis cylinder. 

 Hence the antitoxine is absolutely powerless against the poison 

 when once the latter is in the nerves. Nor can it penetrate even 

 by way of the blood and lymph tracts into the centres. Thus it 

 can only neutralise the excess of poison in the tissues. And this 

 explains why even highly-immuned animals can be poisoned when 

 the poison is introduced directly into their nerves. MEYER and 

 RANSOM hoped to be able to effect a cure by the direct injection of 

 antitoxine into the nerves. 



1 The values given by BEHRING (Die Elutserumtherapie, ii., 20) do not 

 exactly tally. If 1 c.c. protects 50,000 mice, one mouse requires not 

 0-00005 c.c., but 0-00002 c.c., and a horse of 400 kilos, not -25, but 0'4 c.c. 



