Isolation of a Radiation-Mortality Reducing Factor from Spleen

Abstract

THE radiation-mortality reducing action of cell-free extracts obtained from spleens of mice, guinea pigs and dogs has been demonstrated in a series of previous investigations^1,2. The extraction procedure used for preparing spleen extracts has been described elsewhere^2,3. The observation that homologous, as well as the heterologous, spleen extracts were equally effective suggests that a common chemical entity (or entities) may be the therapeutic agent⁴. This is a preliminary report of the isolation and characterization of fractions obtained from dog spleen extracts which contain this factor.