In Vitro Sensitivity of Transplantable Leukemias to Endogenous Granuloid (GCE, GI–2) and Lymphoid (T4, T4–1) Inhibitors of Proliferation

Publisher Website
Google Scholar
Abstract
The effect on cell proliferation of crude granulocyte and thymocyte extracts (GCE, T4) and of their target-specific fractions (Gl-2, T4-1) was studied in cultures with transplantable subacute myeloid and lymphoid leukemia (ML, LL). In the dose rage studied (1–500 μg/ml) each factor reduced 3H-TdR incorporation into acid-insoluble DNA of bone marrow, thymus and spleen cells with ML or LL as a function of the dose, approximately linearly. Normal bone marrow proved to be less sensitive to GCE than the ML one: according to parallel line bioassay by a factor of μ = 0.56. The reactivity of LL spleen and thymus is also higher to medium T4-1 concentrations (50–200 μg/ml) than that of normal lymphoid populations. T4-1 inhibits 3H-TdR incorporation into the DNA of LL spleen cells sub-maximally in 90’: this effect lasts for > 7 hours. Because of its more homogeneous cell composition and higher sensitivity, subacute myeloid leukemia is more suitable for screening endógenous granuloid inhibitors than are homologous normal cell cultures.

This publication has 3 references indexed in Scilit: