1910. | Complement Deviation in. Mouse Carcinoma. 369 
seen that greater complement fixation is obtained in the presence of 
inactivated normal mouse serum than when the tumour extract alone is 
employed. 
Table VII.—Complement Fixation by Mouse Tumour Extract. The contents 
of each tube, after standing at 37° C. for 1 hour were added to 
sensibilised red cells obtained from 0°02 c.c. of a 24-per-cent. suspension 
of the red cells of the rabbit, and the mixture kept, with occasional 
shaking, at 37° C. for a further period of 2 hours. 
Active 0°85 per cent. Heemolysis at end of— 
No. of serum of solution of a ees 
tube. normal sodium a 
mouse. chloride. aan 30 mins. 120 mins. 
Normal Mouse A. 
c.c. Cc: €.c: 
1 0 001 0-02 — Not recognisable Not recognisable 
2 0 003 0 02 —- a ¥ 
3 0 -009 0 02 — Partial Almost complete 
4, 0 027 0 02 — Complete Complete 
5 0-01 — 0 -003 Exceedingly slight Very slight 
6 0°01 — 0 :009 Not recognisable | Exceedingly slight 
Wi 0°01 — 0 :027 $5 Not recognisable 
8 0°01 — 0 054, a i 
Normal Mouse B. 
9 0 -003 0-02 — Very slight Marked 
10 0 009 0 02 — Slight é 
11 0 :027 0-02 — Nearly complete Complete 
12. 0 054 0-02 — * 3 
13 0°01 0°02 0 :003 Slight Nearly complete 
14 0°01 0°02 0 °009 Exceedingly slight Marked 
15 0°05 0-02 0 -003 Marked Complete 
16 0-05 0-02 0-009 Very marked i 
It is also necessary, for the purpose of deciding how much normal mouse 
serum should be employed in the experiments made to determine com- 
plement fixation (Table IX), to ascertain approximately the amount of 
amboceptor corresponding to the antigen contained in the mouse tumour 
extract. It can be seen from Table VIII that the amboceptor present in 
0:01 c.c. of inactivated normal mouse serum,* plus that contained in 0:01 cc. 
of active normal mouse serum, roughly represents the minimum amount 
of amboceptor corresponding to 0°01 c.c. of mouse tumour extract. The 
same relationship appears in Table IX, in which a further series of 
* The same inactivated normal mouse serum, consisting of the mixed sera obtained 
from a number of healthy mice, was used throughout the series of experiments shown in 
Tables VIII to X. 
vious LX Xx X1ll.—B, ok 
