Studies on the in vivo and in vitro multiplication of the LDH virus of mice.

In vivo analysis of the virus titer in various loci, 24 hr after infection, showed that a titer similar to that in the blood plasma was found in the ascitic fluid of Erlich ascites cancer-bearing mice, and in lymph nodes, spleen, and thymus, i.e. loci which contain macrophages as a common cell type.

Some properties of the lactic dehydrogenase agent of mice.

The lactic dehydrogenase agent was obtained in quantities sufficient for purification studies by growing the virus in Ehrlich ascites tumor-bearing mice. A rapid method of titration of the agent is described. Subsequent to the standard procedure of concentration of virus by treatment with hyaluronidase and centrifugation, lipids were removed by extraction with PE, without major loss of infectivity.

Selective localization of tetracycline in mitochondria of living cells.

The property of tetracycline to induce fluorescence has been used to determine its localization in living cells. It was found that this antibiotic, as well as the related antibiotics oxytetracycline and chlorotetracycline, specifically combines with the mitochondria of living cells, either in tissue culture or in fresh preparations from various organs.