Cytotoxic Effect of Mycobacteria on Ehrlich Ascites Cells

Bekierkunst, Adam (Bryn Mawr College, Bryn Mawr, Pa.),and L. Joe Berry . Cytotoxic effect of mycobacteria on Ehrlich ascites cells. J. Bacteriol.89: 205–211. 1965.—Mycobacterium tuberculosis , strains H37 Rv, H37 Ra, and BCG, release into a medium within 3 to 5 hr a substance that is toxic to Ehrlich ascites cells as evidenced by a diminished packed cell volume after 5 to 7 days of growth in the peritoneal cavity of mice. Cell-free extracts of the above strains of mycobacteria display the same type of cytotoxic effect, the strongest action being that of the virulent strain, H37 Rv. The nicotinamide adenine dinucleotidase activity of surviving tumor cells was three to four times greater after treatment with the mycobacterial extracts than that of control cells. The cycotoxicity is probably due to cord factor, because 10 μg of this substance injected intraperitoneally into mice bearing Ehrlich ascites cells inhibited the growth of the cells to 50% of that of control cells. An increase in nicotinamide adenine dinucleotidase activity was found in surviving tumor cells after cord factor treatment.