Vaccination against strontium-90-induced bone tumors.

The thesis was tested that immunization against a murine osteosarcoma virus can reduce the incidence of bone tumors induced by 90Sr. C57BL/6J female mice (190) were divided into three sets of 2 groups. Each set consisted of a control group and an experimental group treated ip with 1.0 muCi 90Sr at 66 days of age. The three sets of groups received the following additional treatments: none (controls), 6 injections of Formalin-inactivated FBJ osteosarcoma virus (vaccinated group), or 6 injections of active FBJ virus (active virus controls). Only 1 bone tumor developed in a mouse not treated with 90Sr in the active virus controls. In 90Sr-treated mice, vaccination reduced bone tumor deaths during the first 600 days from 9 of 36 in controls to 1 of 33 in vaccinated mice (P less than .01), but bone tumor deaths during the entire life-span, 10 of 36 and 5 of 33, respectively, were not significantly different (P = .07). Thus the vaccination procedure delayed the development of bone tumors. In contrast, injection of active virus into 90Sr-treated mice increased the lifetime incidence of bone tumors from 10 of 36 in controls to 19 of 32 (P = .01).