Collodion Sacs 69 
PREPARATION AND USE OF COLLODION SACS IN EXALTING 
MICRO-ORGANISMS. 
CHARLES A. BEHRENS. 
The conception of enhancing the virulence of micro-organisms by 
growing them in vivo in a hermetically sealed permeable membrane 
introduced collodion sacs. By this method the organisms are enabled 
to develop unaffected by the action of the phagocytes and at the same 
time permitting their soluble injurious metabolic products to diffuse 
more or less out while the highly nutritive body fluids of the living 
animal pass in. 
This idea was first attempted in 1893 by Morpurgo and Tirelli* in 
their cultivation experiments with the tubercle bacillus. The bacteria 
were placed in celloidin capsules which were introduced either sub- 
cutaneously or in the peritoneal cavity of rabbits. 
Metchnikoff, Roux and Salimbeni° in 1896 really introduced the 
collodion sac method when they demonstrated that the toxin of the 
cholera germ would very readily diffuse through the walls of these 
sacs when placed in the peritoneal cavity of guinea-pigs. Since then 
this method has received a great deal of attention and notable results 
have been obtained in increasing the virulence of various micro- 
organisms. 
The year of 1898 is rather memorable for its accomplishments along 
these lines. The germ of pleuro-pneumonia was successfully cultivated 
at this time by Nocard and Roux* by utilizing the collodion sac method. 
During this year by using this method Nocard* increased the patho- 
genesis of the tubercle bacillus, which was human in origin, so that it 
proved fatal to chickens. 
At this time Vincent,’ employing the method, pursued his research 
upon converting saprophytic bacilli (B. megaterium and B. mesenteri- 
cus vulgatus) into pathogenic types. 
Podbelsky*® by applying the same principle showed the destruction 
of the spores of the Hay bacillus in vivo. Due to the difficulty of pre- 
paring collodion sacs he made tubes out of reeds. A reed sac, which is 
even more permeable than one prepared of collodion, is made from the 
tubular membrane lining the central canal of the bulrush. 
It is prepared briefly as follows: Common bulrush reeds, if fresh, 
are boiled for about 15 minutes. If dry, they should be autoclaved for 
60 minutes at 115° C. The end of the softened reed is sharpened as 
1 Archives Ital. de Biologie, Vol. XVIII, p. 187—1893. Ref. in Centrabl. f. Bacteriol., 
Bd. XIII, p. 74—1893. 
2 Annales de L’ Institut Pasteur, Vol. X, p. 261—1896. 
3 Annales de L’ Institut Pasteur, Vol. XII, p. 240—1898. 
# Annales de L’ Institut Pasteur, Vol. XII, p. 564—1898. 
> Annales de L’ Institut Pasteur, Vol. XII, p. 787—1898. 
6 Annales de L’ Institut Pasteur, Vol. XII, p. 431—1898. 
