Response of a Virus-induced Leukemia in Mice to High Oxygen Tension^*

Effects of repeated short treatments with high pO₂ (oxygen partial pressure), at about 2.5 atm. and administered over a relatively long period, on the course of a leukemia induced by Friend virus were investigated. Treatment with high pO₂ during the first 3 or 6 weeks, or even during the second 3 weeks of the disease, reduced the intensity of leukemic symptoms markedly below those in the untreated inoculated group, but the effect was not permanent.

It is argued that the beneficial effects of high pO₂ treatment should be regarded at least in part as being due to a specific availability of higher than normal tissue pO₂'s, rather than simply to the relief of hypoxia inside tumorous masses.