Immune response of mice to sarcoma I allograft studied by adoptive transfers of spleen, thymus, and lymph node cells to secondary recipients

Abstract

Thymus, spleen, and lymph node cells from different periods of Sarcoma I allograft development in untreated (Sa I) or xenogeneic antithymocyte serum-treated (ATS-Sa I) B10 mice were adoptively transferred to secondary B10 recipients. While in sublethally (4.3 Gy) irradiated recipient mice the tumor destructing activity was predominantly expressed, in untreated recipients of transferred cells it was mostly the tumor enhancing activity. Therefore, in further studies directed at the detection of tumor enhancing activity, the adoptive transfers were only performed in untreated recipients. Thymus cells both of Sa I and ATS-Sa I mice showed a tumor enhancing activity all through the followed period, with a peak between days 7 and 21, then it decreased. Also the spleen cells of both groups had a tumor enhancing effect all the time, with a peak of activity on day 7. Spleen and thymus cells of progressors enhanced the tumor growth slightly more strongly than did those of the regressors. The tumor enhancing activity of spleen cells was in the beginning period confined mainly to the polystyrene nonadherent fraction of cells, at later times, in the progressors it was manifested in the adherent as well as in the nonadherent fractions. In the population of lymph node cells, at the start of tumor regression (in Sa I mice on day 7, in ATS-Sa I mice on day 14), a tumor destructing activity was observed. In both groups this activity was at later times followed by a tumor enhancing activity. The interpretation of the tumor enhancing activity of thymus and spleen cells of Sa I and ATS-Sa I mice is complicated by the tumor enhancing activity of cells of normal mice without tumor (N).