Preparation of cholera vaccines by fluorocarbon extraction of cholera Vibrio suspensions.

Experimental cholera vaccines were prepared from suspensions of cholera vibrios which were extracted with Genetron-113. These vaccines, when compared with a control preparation which was not treated with Genetron, had a lower nitrogen content and were less toxic for mice but were as effective in protecting mice against infection and in inducing agglutinating and vibriocidal antibody responses in rabbits. This procedure may permit the preparation of cholera vaccines with a higher antigenic content without the corresponding increase in toxic reactions.

Freeze-drying various strains of Shigella.

Of six candidate strains of Shigella prepared in Brain Heart Infusion broth as freeze-dried vaccine, low survival rates were obtained with two of the most promising strains. Survival rates with these two strains were increased to acceptable levels when the organisms were suspended in a medium consisting of 8.2% sucrose, 0.

BACTERIAL VACCINE IN MULTIDOSE TABLET FORM FOR PARENTERAL USE.

Dried typhoid vaccines were prepared by freeze-drying of heat-inactivated phenolized-cell suspensions and by an acetone-killed and dried technique. Portions of the dried powder obtained by each method were compressed into tablets. Tests with the products showed that drying and making of tablets did not affect the ability of the vaccines to protect mice or elicit antibodies in rabbits.

Enzymatic debridement of third-degree burns on guinea pigs by Clostridium histolyticum proteinases.

Webster, Marion E. (Walter Reed Army Institute of Research, Washington, D. C.

Large scale purification of proteinases from Clostridium histolyticum filtrates.

Conklin, David A. (Walter Reed Army Institute of Research, Washington, D. C.

Factors affecting the elaboration by Clostridium histolyticum of proteinases capable of debriding third degree burn eschars on guinea pigs.

Berman, Sanford (Walter Reed Army Institute of Research, Washington, D. C.), Joseph P.