Properties of the Causative Agent of a Chicken Tumor

A brief description is given of the main physical and chemical characteristics of active chicken tumor extracts. By special methods constituents have been removed from the active solution: (1) the major part of the tumor-proteins, which are adsorbed on alumina gel and discarded; (2) a carbohydrate, present in large amounts in the tumor extract, is eliminated by precipitation in combination with gelatin. In both cases the tumor principle is not directly affected and largely remains in active form in the solution.