Upon an anti-cholera serum / by Allan Macfadyen, M.D. Edin, Fullerian professor of physiology, Royal Institution.

  • Macfayden, Allan, 1860-1907
Date:
[1906?]
Catalogue details

Licence: In copyright

Credit: Upon an anti-cholera serum / by Allan Macfadyen, M.D. Edin, Fullerian professor of physiology, Royal Institution. Source: Wellcome Collection.

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    body for the cholera endotoxin. It was also evident that one was dealing with an active toxin. The further immunising experiments were carried out on the goat and the intravenous method of injection was employed. This animal is highly susceptible to the action of the cholera endotoxin, as will be seen from the figures already given, and a careful method of dosage is necessary for successful immunisation. A goat received intravenously at intervals of a week x£oth, 55th, TVth, Jth, and Jth cubic centimetre of toxic cell juices. The animal was ill after the first injection and the subsequent doses produced' distinct reactions. The serum was tested after the sixth injection. The results are given in the accompanying table :— Guinea-pig. Dose. Result. 1 2 c.c. toxin + 2 c.c. serum. Alive. 2 2 c.c. „ +1 c.c. „ Dead. 3 2 c.c. 99 *}“ 2 c.c* 99 Alive. 4 1 c.c. „ +2 c.c. „ II 5 1 c.c. 99 + 1 c.c. 99 99 6 1 C.C. „ + 5 C.c. „ 91 The cell juice contained four ascertained lethal doses in one cubic centimetre. The figures therefore show that one- half cubic centimetre of the serum protected against eight lethal doses of the endotoxin. It had been previously ascer¬ tained that one cubic centimetre normal goat’s serum will not protect against two lethal doses of the poison, nor, as a matter of fact, was there any appreciable action in two cubic centimetres of normal serum. A second goat was treated more deliberately and for a longer period, beginning with sublethal initial doses of the endotoxin, and tolerance was established to otherwise fatal amounts. The weekly injections made were T£7th, T£<yth, bV^, sjj-th, ^yth, -30th, jfoth, 2Joth, ^th, TVth, t^th, TVth, T2th, rs^h, and ^rd cubic centimetre. The animal was ill after the first injections of ^th, -gVth, ^yth, and Tjth cubic centimetre. The total amount injected was about one cubic centimetre, or 10 milligrammes, of solid matter. The injections extended over four months, the animal at the end of that time being alive and well. In the case of this goat the neutralising power of its serum was always tested against the same amount of toxic cell juice— viz., one cubic centimetre, and containing from three to five