Yarkoni E, Rapp H J
Cancer Res. 1980 Apr;40(4):975-8.
The influence of Tween 80 content on the antitumor activity of emulsified mycobacterial components administered intralesionally was studied in mice. The number of treated animals in which there was complete regression of tumor depended on the concentration of Tween in each of the emulsions. An additional variable was the size distribution of the mineral oil droplets, which depended on whether the emulsions were prepared by ultrasonication or by mechanical grinding. Emulsions of mycobacterial components (cell walls of Bacillus Calmette-Guérin and trehalose-6,6'-dimycolate) prepared by ultrasonication contained smaller oil droplets than did those prepared by grinding. Ground emulsions retained antitumor activity over a wider range of Tween concentrations than did ultrasonically prepared emulsions. The latter required Tween at concentrations in an optimal range above which the tumor-regressive potency was diminished. Emulsions of trehalose-6,6'-dimycolate containing the lowest concentration of Tween needed to produce a relatively stable preparation contained larger oil droplets and were immunotherapeutically less active than were those prepared with an optimal concentration of Tween. Emulsions of B. Calmette-Guérin cell walls retained antitumor activity even in the absence of added Tween.
