Effects of splenectomy on pulmonary metastasis and growth of SC42 carcinoma transplanted into mouse liver

Abstract

The carcinoma SC42 was transplanted into the liver of its syngeneic mice DS, and the immunological integrity of the spleen and the effects of splenectomy on the growth and pulmonary metastasis of the liver tumor were assessed. On day 7 after liver tumor transplantation, the natural killer (NK) activity of the splenocytes was significantly elevated; it subsequently decreased at a later stage of the tumor. The response of the splenocytes to PHA and Con-A decreased significantly from the early stage of the tumor. However, the mixed lymphocyte-tumor cell reaction increased significantly from day 14 to day 28. The survival rate of the mice, which had undergone simultaneous splenectomy and liver tumor transplantation, was significantly lower than that of sham-operated control mice. The number of pulmonary metastases in splenectomized mice was significantly greater than in the control mice. There was, however, no difference between the two groups in the weight of the liver tumor. By contrast, splenectomies performed 14 days before or 14 days after tumor transplantation had no significant influence on the survival of the mice. Splenectomies performed on day 0 and on day 3 after tumor transplantation significantly increased the number of pulmonary metastases. Furthermore, the intravenous injection of anti-asialo GM1 antisera on day 0 and day 3 significantly increased the number of pulmonary metastases, but injection of anti-Thy 1.2 antisera had no effect. These results suggest that splenic NK cells may play an important role in the suppression of pulmonary metastasis at early stages of the liver tumor.

Monocytes control natural killer cell differentiation to effector phenotypes

“…The experiments of our study provide clear evidence for a division of labor among NK-cell subsets and demonstrate that incomplete NK-cell differentiation observed in Txb21-deficient mice may lead to a deficit in effector antitumoral NK-cell subsets. Furthermore, our findings may also explain the increased NK cell-dependent incidence of pulmonary 45 and hepatic 46 metastasis reported in splenectomized mice.…”

Fluorescence-guided Surgery with Splenic Preservation Prevents Tumor Recurrence in an Orthotopic Nude-mouse Model of Human Pancreatic Cancer

“…One of the possible mechanisms is that the activity of natural killer (NK) cells can decrease after splenectomy. Imai et al reported the number of pulmonary metastases in splenectomized mice was significantly greater than in the control group and they suggested that splenic NK cells play an important role in the suppression of pulmonary metastasis in the mouse liver tumor model (17).…”

Inoculation of Human Interleukin-17 Gene-Transfected Meth-A Fibrosarcoma Cells Induces T Cell-Dependent Tumor-Specific Immunity in Mice

“…The cytotoxic activity of splenocytes was tested in a standard 4-hour 51 Cr release assay, as described previously [25]. Cytotoxicity was assessed against the Yac-1 cell line as an NK target and Meth-A cells.…”

“…For depletion of T cells, mice were injected intravenously with 40 µg of anti-thy 1,2 (CD90) mAb (Cedarlane), anti-CD4 mAb (clone H129.19, rat IgG2a; PharMingen, San Diego, Calif., USA) or anti-CD8 mAb (clone 53-6.7, rat IgG2a; PharMingen), and for depletion for NK cells, 100 µl of anti-asialo GM1 antiserum (Wako Pure Chemical Industries Ltd., Osaka, Japan) diluted at 10/1 was injected into each mouse through the caudal vein, 1 day before tumor cell injection, according to the manufacturer’s instructions and previously published methods [25, 26, 27, 28]. …”

“…The mixed lymphocyte tumor cell reaction (MLTR) was assessed as described previously [25]. Splenocytes of BALB/c mice were used as responder cells 1, 2 and 3 weeks after injecting the mice with 1 × 10 4 parental Meth-A, Meth-A/neo or Meth-A/IL-17 cells.…”