Effect of antiserum on transplantable hematopoietic colony‐forming units during rauscher leukemia development

Abstract

Studies have been carried out to determine the sensitivity of hematopoietic CFU-S from Rauscher leukemic mice to an antiserum against the disease prepared in syngeneic mice. Test of this antiserum against Rauscher virus prior to injection showed it to be effective both in vitro and in vivo. At the same time, normal serum was shown to be without effect either against the CFU-S or against the virus. Spleen CFU-S were obtained from control and leukemic mice over a sequence of days following Rauscher virus injection and assayed by transplantation technique. Prior to transplantation these were incubated in vitro in either normal syngeneic serum or syngeneic antiserum. Incubation with antiserum had no effect on CFU-S obtained from the spleens of normal mice. However, incubation in this antiserum of spleen CFU-S from Rauscher leukemic mice resulted in a reduction of up to 50% in their colony-forming ability. Additional tests with guinea pig complement suggested that the levels of inactivation seen are not complement limited. This antiserum-induced reduction in colony formation was first evident in the second week after the injection of virus, coincident with the onset of splenomegaly in the leukemic mice. Thereafter, sensitivity of CFU-S to the antiserlm could be detected up to the terminal point of the leukemia (44 days).

Effect of chemical carcinogens on hematopoietic stem cells: temporal correlation between methyl methane sulfonate induced depression of CFU-S and potentiation of Friend viral leukemogenesis in vivo. [Mice]

“…These can be called into active cell cycle by a partial destruction of the stem cell pool, such as occurs with radiation, which is known to be a potentiating agent for murine viral leukemia (22,23). Regan Additional mechanisms could possibly be also proposed, but one of these, that of immunosuppression by MMS thereby reducing the animal's ability to destroy leukemogenic virus by antibody action (24,25), does not seem highly probable in view of the fact that the present data indicates that the immunosuppressive effect of MMS on antibody producing PFC does not coincide with the timing for the potentiating effect of the chemical.…”

Stimulation of Immune Response in Hybrid Mice Following Rauscher Virus Infection

“…The data of this paper gives positive evidence that enhancement of the humoral antibody plaque forming cell response can be demonstrated following leukemia virus infection. The significance of this lies in the fact that humoral antibody formation is known to play a role in the induction of immunity to leukemia virus in otherwise sensitive mice following the injection of killed virus and leukemia cells (15)(16)(17). For other strains, including the group to which the C57B1/10 belongs, it has also been established by in vitro studies that one control of resistance to infective oncorna virus rests directly at the level of the target cell, unmediated by immune response (18)(19)(20).…”

Effects of chemical carcinogens on hemopoiesis, immunopoiesis and viral oncogenesis. Three year technical progress report, February 1, 1977-September 30, 1979. [MMS; BP; DMBA; propane sultone; MCA; mice]

“…Too large a dose of virus, when given to the virus sensitive mice, results in 100% incidence of leukemta, with all of the test mice dying rapidly within 20 to 60 days, . Thus any possible potentiating effect of the chemical carcinogen would be obscured by the action of the virus alone.Conversely, too low a dose of virus results in a subthreshold response for leukemogenesis in which not only does no disease develop, but the animals may show an enhanced immune response to the leukemia antigen and possibly build an immunity against the leukemia(10,12,13). Therefere, due to the inherent difficulties in obtaining an exact titer for number of leukemogenically active virus particles, each potentiation experiment must be carefully controlled, and the response to chemical carcinogen plus virus compared each time…”