ON THE ANTITOXIN CONTENT OF SOME GAS GANGRENE SERA USED IN THE LATER STAGES O F THE WAR.*

By HERBERT HENRY, M.D.

( A Report to the Medical Research Conznc-ittee from the Wellconae Physiological Research Laboratories, Herne Hill.)

SPECIMENS of gas gangrene sera were captured in the German lines by British troops for the first time in the autumn of 1917. These earlier specimens were prepared a t the well-known Hoechst works of Meister Lucius and Bruning, and were used in German field hospital units both prophylactically and therapeutically.

The examination of these sera was a matter of more than usual interest from the fact that enemy bacteriologists had described, as the causal agent in human gas gangrene, a new bacillus which so far had not been encountered by Allied workers. It is now certain that Conradi and Bieling, Aschoff and others, were dealing with mixed cultures in the belief that they were pure, and that these mixed cultures contained species of anaerobes which were already clearly defined in the literature published by Allied investigators.

It was found that the German sera contained agglutinins to certain types of Bcicilhs sporogenes and of Yibrion septique, a fact which proved that whole cultures or washed suspensions of these organisms were used at some period in the immunisation of the horses. The sera, however, had no protective value when tested in guinea-pigs against a lethal dose of V, septigue culture or of B. welchii culture. On the other hand, they did establish protection against a lethal combination of B. sporoyenes with B. welchii. We found that the amount of B. welchii in such a fatal combination need be no more than & to 2g of the lethal dose of a pure B. welchii culture. It appeared possible, therefore, that the B. sporogenes agglutinin by itself might play some part in the protection afforded by these sera. Accordingly, high titre agglutinat- ing sera against 3. sporogenes were prepared in a sheep and in a goat ; but these sera, when tested, yielded no evidence of protection against the W elchii-sporogenes combination. Later, we found that these earlier Hoechst sera contained a small amount of antitoxin to B. welchii, which was not sufficient to check infection by a pure culture of the

Received January 5 , 1920.

ANTITOXIN CONTENT OB GAS GANGRENE SERA 271

0 ! : 0

I 0 0 0 0 0 0

100 100 100 100 250

organism, but which was capable of inhibiting the development of the small amount of B. welchii present in the Welchii-sporogenes combination.

At a later period, in 1918, large quantities of serum were found in captured German lines, and numerous specimens were sent to us for examination. At this time we had acquired a certain amount of information in regard to the toxins produced by the organisms which are mainly responsible for gas gangrene in man, and we were in a position t o estimate the antitoxin content of the German serum. These later specimens of serum came from three different sources :-

1. The Hoechst works of Meister Lucius and Bruning. 2. The Ludwig Wilhelm Gans laboratory a t Oberursel. 3. The Behringwerke a t Bremen and Marburg.

The unitage of each antitoxin has been measured on the following basis :-

A. The unit of E. zvelchii antitoxin is twice the smallest amount of serum that is sufficient to neutralise two minimal lethal doses of toxin in a 20-grm. mouse, the mixture of toxin and serum being kept in contact for one hour a t room temperature before inoculation.

B. The unit of V. septipue antitoxin is the smallest amount of serum which will neutralise the lethal effect of one minimal lethal dose of V. septipue toxin given intravenously to a full-grown rabbit, the mixture of toxin and serum being kept at room temperature for one hour before inoculation. I n practice, one uses a multiple of the lethal dose in the toxin-antitoxin mixture.

C. The unit of E. adematiens serum is the smallest amount of serum which will neutralise 1 0 0 minimal lethal doses of B. adernatiens toxin in a 20-grm. mouse, the mixture of toxin and antitoxin being kept a t room temperature for one hour before inoculation.

Table I. THE ANTITOXIN CONTENT OF SOME GERMAN GAS CEDEMATIENS SERA.

B. welchii Units. I Serum.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

V. septique Units.

< 40

< 40 <40

... < 40

80 < 40

40 < 40 < 40

250 260 150 200 200

B. adematiens Units.

0 0 0

0 5

...

...

...

... 0

...

...

...

... 0

272 ANTITOXIN CONTENT OF GAS GANGRENE SERA.

It will be seen from Table I. that in the matter of antitoxin content the Hoechst and Gans sera were of little value. The i? septipe antitoxin titration was not carried to end-points because it was not deemed necessary to sacrifice aninials for this purpose. The Behring sera contaiued a moderate value in V. septique antitoxin, but were very poor in 5’. welclzii antitoxin and destitute of B. cedematiens antitoxin.

The British sera in use during the later stages of the war were made by O’Brien and his staff a t the Wellcome Physiological Research Laboratories.

Table 11. THE ANTITOXIN COXTEST OF THE BRITISH GAS GANGRENE SERA.

Seruiii.

G 2 . . . . G 3 . . . . G 1 7 . . . . G18 . . , . G I 9 . . . . G 2 2 . . . . G 4 4 . . . . G 5 3 . . . . Weinberg’s, 810 . .

8. u e l c h i i .

2000

1000

1000

500

500

2000

2500

1000

1250

V . septique.

0

80

80

80

80

0

. 300

800

750

~

B. mlematiens.

0

0

0

0

0

0

0

0

8000

These sera showed a very good B. welcki i antitoxin content, and the later batelies in the series contained, in addition, a large amount of I? septique antitoxin. The unitage of the British sera has been estimated on the same basis as that which obtained in the titration of the German sera, so that the figures are strictly comparable.

With the exception of Weinberg’s serum, 810, we have had no opportunity of examining the French sera. This particular serum shows a remarkably high amount of each antitoxiu. It is a single- horse serum, and was therefore not available in large amounts.