The titration of scarlet fever antitoxin in rabbits / by H.J. Parish and C.C. Okell.

  • Parish, H. J. (Henry James)
Date:
1927?]
Catalogue details

Licence: In copyright

Credit: The titration of scarlet fever antitoxin in rabbits / by H.J. Parish and C.C. Okell. Source: Wellcome Collection.

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    Reprinted from The Lancet, Jan. 8th, 1927, p. 71. i1 ir THE TITRATION OF SCARLET FEVER ANTITOXIC IN RABBITS. By H. J. PARISH, M.D., M.R.C.P. Edin., AND C. C. OKELL, M.C., M.B. Camb., M.R.C.P. Lond. (From, the Wellcome Physiological Research Laboratories.) It is generally admitted that one of the most urgent needs in connexion with recent work on scarlet fever is a method of titrating toxin and anti¬ toxin by some means other than on human subjects. Up to now the only promise of an animal test has come from the researches on goats of Kirkbride and Wheeler,1 but the work has not yet been generally confirmed and the method is complicated by many difficulties. Many attempts have been made in the past to measure in various laboratory animals, particularly mice and rabbits, the protective value of antibacterial sera against living cultures of streptococci. The results of most of this work in our own and other workers’ experience have been disappointing. It has been found, however, that rabbits could be killed with reasonable regularity by the intravenous injection of the “ Dochez ” streptococcus and certain other scarlet fever strains. If the rabbits were injected intravenously 4 to 6 hours previously with an adequate amount of scarlet fever antitoxin, death did not take place or was delayed beyond the sixth day. 10 c.cm. of a 20-hour tryptic digest broth culture of the Streptococcus scarlatince, given intravenously, killed in successive experiments 70 per cent, of 63 rabbits of medium weight within 48 hours and 92 per cent, within six days. 5 c.cm. of uncon¬ centrated and 1 c.cm. or less of concentrated scarlet antitoxin protected the great majority of rabbits. The protected animals, which survived for a longer 1 Kirkbride, Mary B., and Wheeler, Mary W. : Proc. Soc„ Exper. Biol, and Med., 1924, xxii., 86.