A variety of heat-killed bacteria were tested for their capacity to induce regressions of established line 10 hepatocarcinomas in syngeneic guinea pigs. Multiple intralesional injections of heat-killed Escherichia coli, Streptococcus mutans, Listeria monocytogenes, and Propionibacterium acnes resulted in complete regression of the tumor in a majority of guinea pigs. Repeated injections of heat-...

1. Rabbits vaccinated with tubercle bacilli killed by exposure to formalin (0.4 per cent) did not show any acquired resistance to subsequent infection with bovine tubercle bacilli, while rabbits vaccinated with tubercle bacilli which had been killed by heating to 70 degrees for 1 hour survived more than half as long again as their controls. 2. Intraperitoneal injection of either the formalin-ki...

Doering, Alice McGovern (University of Pennsylvania School of Medicine, Philadelphia), Miekie Jansen, and Seymour S. Cohen. Polymer synthesis in killed bacteria: lethality of 2',3'-dideoxyadenosine. J. Bacteriol. 92:565-574. 1966.-We studied the metabolic capabilities of cells that had lost the ability to multiply under a variety of lethal treatments. Cultures of a polyauxotrophic mutant of Esc...