asialo-gm1-ganglioside and Fibrosarcoma

Tumor dormancy is a clinical phenomenon related to immune equilibrium during cancer immunoediting. The mechanisms involved in dormant metastases are poorly understood due to the lack of preclinical models. Here, we present a nontransgenic mouse model in which spontaneous metastases remain in permanent immunomediated dormancy with no additional antitumor treatment. After the injection of a GR9-B11 mouse fibrosarcoma clone into syngeneic BALB/c mice, all animals remained free of spontaneous metastases at the experimental endpoints (3-8 months) but also as long as 24 months after tumor cell injection. Strikingly, when tumor-bearing mice were immunodepleted of T lymphocytes or asialo GM1-positive cells, the restraint on dormant disseminated metastatic cells was relieved and lung metastases progressed. Immunostimulation was documented at both local and systemic levels, with results supporting the evidence that the immune system was able to restrain spontaneous metastases in permanent dormancy. Notably, the GR9-B11 tumor clone did not express MHC class I molecules on the cell surface, yet all metastases in immunodepleted mice were MHC class I-positive. This model system may be valuable for more in-depth analyses of metastatic dormancy, offering new opportunities for immunotherapeutic management of metastatic disease.

Topics: Animals; Cell Line, Tumor; Fibrosarcoma; G(M1) Ganglioside; H-2 Antigens; Male; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; T-Lymphocytes

We evaluated the mechanism of the antitumor effects of mouse rIFN-gamma-inducing factor/IL-18 protein on the growth of mouse tumor cell lines in vivo. Mice received IL-18 before or after challenge with CL8-1, a mouse melanoma cell line. Both regimens significantly suppressed tumor growth and reduced the number of mice with growth of tumor from 60% (3/5) to 20% (1/5). Furthermore, IL-18 administered before and after tumor inoculation completely abrogated the establishment of CL8-1 in all animals. IL-18 administration also significantly suppressed the growth of MCA205, a sarcoma cell line, even when treatment was delayed to 7 days following tumor inoculation. Although IL-18/IL-12 combination therapy had the most significant and immediate antitumor effects, many mice so treated succumbed with markedly elevated serum IFN-gamma levels. The antitumor effects of IL-18 were abrogated almost completely when NK cells were eliminated using anti-asialo GM1 Ab administration, but only marginally impaired in IFN-gamma or IL-12 gene-disrupted mice. Immunohistochemical staining revealed that the number of the CD8+ T cells, but not CD4+ T cells, found at the tumor site was reduced in animals treated with IL-18. These results indicate that IL-18 has potent antitumor effects mediated by CD4+ T cells and NK cells, but in IFN-gamma- and IL-12-independent pathways.

Topics: Adjuvants, Immunologic; Animals; Antineoplastic Agents; CD4-CD8 Ratio; CD8-Positive T-Lymphocytes; Cytokines; Cytotoxicity, Immunologic; Fibrosarcoma; G(M1) Ganglioside; Gene Deletion; Growth Inhibitors; Immune Sera; Injections, Intraperitoneal; Interferon Inducers; Interferon-gamma; Interleukin-10; Interleukin-12; Interleukin-18; Killer Cells, Natural; Lymphocyte Depletion; Melanoma, Experimental; Mice; Mice, Inbred C57BL; Mice, Knockout; Neoplasm Transplantation; Sarcoma, Experimental; Tumor Cells, Cultured

A 3-methylcholanthrene-induced fibrosarcoma cell line of BALB/c origin, CMS5j, was co-transfected with cDNA for the p40 and p35 subunits of interleukin-12 (IL-12). Injection of transfected cells producing 5 x 10(3) U IL-12/10(6) cells/ml/day in nude mice with an established fibrosarcoma at a contralateral site efficiently eliminated tumor growth in the early phase (injection on day 0 or 4) but not later (day 8). This effect could be abrogated by simultaneous i.v. injection of antibodies against NK1.1 or ASGM1 (asialoGM1 = ganglio-N-tetraosyl-ceramide), which indicates that natural killer (NK) cells play a major role in tumor eradication or suppression when stimulated by IL-12. In wild-type mice, application of IL-12-secreting CMS5j cells abrogated growth of tumors established 8 days before but not earlier. Based on our experiments with antibody blocking in vivo, all CD4+, CD8+ and ASGM1+ cells are involved in tumor rejection. However, in our system, CD4+ cells or CD8+ cells alone, but not ASGM1+ cells alone, also could lead to tumor rejection. IL-12-engineered fibrosarcoma cells may constitute an efficient and safe system for immunotherapy of cancer.

Topics: Animals; Antibodies; Cell Division; Female; Fibrosarcoma; G(M1) Ganglioside; Immunization, Passive; Interleukin-12; Killer Cells, Natural; Methylcholanthrene; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; T-Lymphocyte Subsets; Transfection; Tumor Cells, Cultured

We studied the effect of protein-bound polysaccharide PSK on metastatic colonization of BALB/c mice after intravenous injections of different syngeneic murine H-2 positive and H-2 negative tumor clones. The tumor lines used were different clones from chemically induced fibrosarcomas (GR9.B9, an H-2 negative clone from GR9 tumor, and B7.1.B4, an H-2 positive clone from B7.1 tumor). These clones were selected because of their different sensitivity to NK cytotoxicity, which was related to MHC class I expression. Pretreatment of mice with PSK inhibited metastatic colonization derived from B9 H-2 negative tumor cells. In contrast, lung colonization of PSK treated mice injected with B7.1.B4 H-2 positive tumor cells was higher, and differences in the number of colonies between untreated and PSK treated mice were small. In several experiments the effect of PSK was attenuated to a greater degree when high numbers of cells were injected. Abrogation of NK cells with anti-asialo GM1 serum significantly increased (in all tumors and at different cell doses) the number of metastatic colonies in comparison with untreated mice injected with tumors, regardless of the cell dose used. These results clearly suggest that NK cell activation in vivo by the protein bound polysaccharide PSK abrogates metastasis formation in mice. Abrogation was dependent on the H-2 phenotype even when pretreatment consisted of a single dose of PSK. This effect, related to the NK sensitivity of the tumor target, can be used to predict the effect of PSK in vivo.

Topics: Animals; Antibiotics, Antineoplastic; Clone Cells; Cytotoxicity, Immunologic; Dose-Response Relationship, Immunologic; Fibrosarcoma; G(M1) Ganglioside; H-2 Antigens; Immune Sera; Injections, Intravenous; Killer Cells, Natural; Kinetics; Lung Neoplasms; Lymphocyte Subsets; Mice; Mice, Inbred BALB C; Neoplasm Transplantation; Proteoglycans; Sarcoma, Experimental; Spleen; Tumor Cells, Cultured

The role of different tilorone analogs in the abrogation of the metastatic spread of H-2 positive and H-2 negative tumor clones was studied. Pre-treatment of BALB/c mice with RMI 10,874DA compound completely abolished lung colonization of an H-2 negative (GR9.B9) MCA-induced fibrosarcoma clone in an experimental metastasis assay. This effect was also evident when clones were treated with other tilorone analogs (R11,567DA or R11,513DA). Other H-2 positive and H-2 negative chemically induced fibrosarcoma clones were also tested. The effect was not due to direct toxicity of the tilorone analog on tumor cells, but instead was dependent on NK cells; this was suggested by the finding that treatment of mice with anti-asialo GM1 abrogated the effect of the tilorone analog (RMI 10,874DA compound). Interestingly, the inhibition of lung colonization after intravenous injection was again observed regardless of the H-2 phenotype of the tumor clones, and H-2+ and H-2- clones were similarly inhibited. In vitro assays of NK sensitivity of tumor clones showed that lysis varied depending on the H-2 phenotype of tumor clones, indicating an absence of correlation between in vivo and in vitro results.

Topics: Animals; Cytotoxicity, Immunologic; Fibrosarcoma; G(M1) Ganglioside; H-2 Antigens; Immune Sera; Killer Cells, Natural; Lung Neoplasms; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Tilorone

In the present study, the respective roles of T cells and their subpopulations as well as of NK (natural killer) cells in antitumor immune responses were followed using the SaI (H-2a) allograft model. The development of this tumor in B10 (H-2b) mice was evaluated after pretreatment of the recipients with xenogeneic antithymocyte serum (ATS). Anti-Thy 1.2, anti-Lyt 2.2 and anti-L3T4 monoclonal antibodies were used in order to determine T lymphocyte phenotypes and to assess the frequency of TC/S and TH subpopulations at various periods of tumor development. Rabbit polyclonal anti-asialo GM1 antiserum was used for the identification of NK cells. In a previous work it was suggested that the first week following transplantation, the cells predominantly involved in the growth regulation of SaI belong to the TS subclass. Our results based on the use of anti-Lyt 2.2 monoclonal antibodies have further supported this finding. The application of anti-Thy 1.2 on the 3rd and 5th day has hampered a secondary tumor growth while anti-Lyt 2.2 was effective when given on day 5. The depletion of Lyt. 2.2+ cells on day 3 resulted in the inhibition of both primary and secondary tumor development. On the other hand, when anti-Thy 1.2 was applied on day 7 after transplantation, the primary and secondary tumor growth was strikingly enhanced. It appears that Thy 1.2+ lymphocytes display at this period effector functions and contribute, in conjunction with macrophages, to subsequent tumor regression. The depletion of L3T4 cells on days 3 and 5 after tumor inoculation has resulted in primary tumor growth enhancement. This suggests that cells of the L3T4+ phenotype display at this time helper functions contributing to CTL proliferation and maturation. A further indication, supporting the possible suppressor effect of L3T4+ cells, counts from the finding that anti-L3T4 treatment results in an inhibition of secondary tumor growth. The anti-asialo GM1 treatment has not enhanced, at least significantly, primary tumor development but has partially or totally inhibited the growth of secondary tumors. It appears that cells of the GM1+ (NK cells) phenotype do not participate in any substantial way in the early phases of SaI tumor development in ATS treated allogeneic recipients.

Topics: Animals; Antibodies, Monoclonal; Female; Fibrosarcoma; G(M1) Ganglioside; Immunity, Cellular; Immunophenotyping; Isoantibodies; Killer Cells, Natural; Mice; Mice, Inbred A; Mice, Inbred C57BL; Neoplasm Metastasis; Neoplasm Transplantation; T-Lymphocytes; Time Factors; Transplantation, Homologous

An intravenous injection of bacterial lipopolysaccharide (LPS) into mice exerted prominent antimetastatic activities against a NK-resistant weakly immunogenic NFSa fibrosarcoma. The number of visible metastases in the lung was increased by a pretreatment of anti-asialoGM1 (asGM1) antibody or silica, but pretreatment of asGM1 antibody or silica scarcely affected the antimetastatic activities of LPS. The pulmonary retention of radiolabeled tumor cells showed that LPS accelerated the detachment of the tumor cells from the lung, and that this acceleration was not suppressed by anti-asGM1 antibody. Sialic acids of lung endothelial cell surface, essential components of various receptors, was diminished by the i.v. injection of LPS. These results suggested that the antimetastatic effect of LPS against NK-resistant NFSa cells was partly the result of modulations of lung endothelial cell surface.

Topics: Animals; Antibodies; Fibrosarcoma; G(M1) Ganglioside; Killer Cells, Natural; Lipopolysaccharides; Lung Neoplasms; Male; Mice; Mice, Inbred C3H; Neoplasm Transplantation; Sialic Acids; Silicon Dioxide; Specific Pathogen-Free Organisms

The aim of this study was to investigate the influence of oral administration of OK-432 on the tumor growth of tumor-bearing mice. In addition, the changing pattern of the splenic lymphocyte subsets of tumor-bearing mice was evaluated by flow cytometry. OK-432 at a dose of 0.1, 1 or 10 KE was administered orally every 3 days or every other day for 30 days to subcutaneously Meth A tumor-inoculated mice. The tumor growth was significantly inhibited in the 1 KE every 3 days group, in the 1 KE every other day group and in the 10 KE every 3 days group. In the 10 KE every other day group, OK-432 inhibited the tumor growth on days 10 and 20, while the agent did not show a marked inhibitory effect on day 30. The percentages of splenic L3T4-positive cells and splenic asialo GM1-positive cells were significantly increased in the 1 KE every other day group, while the Lyt2+/Thy1.2+ ratio was decreased. On the other hand, in the 10 KE every other day group, OK-432 showed no effect on the percentages of splenic L3T4-positive cells and Lyt2+/Thy1.2+ ratio on days 20 and 30. Our results suggest that the antitumor effect of oral administration of OK-432 may be correlated with the changing pattern of L3T4-positive cells and Lyt2+/Thy1.2+ ratio.

Topics: Administration, Oral; Animals; Antigens, Ly; Antigens, Surface; Antineoplastic Agents; Fibrosarcoma; Flow Cytometry; G(M1) Ganglioside; Lymphocyte Subsets; Male; Membrane Glycoproteins; Mice; Mice, Inbred BALB C; Picibanil; Spleen; Thy-1 Antigens

OK-432, a streptococcal preparation with potent biological response modifying activities, had the ability to cure mice bearing BAMC-1 (fibrosarcoma) ascites when it was injected intraperitoneally five times, 2, 4, 6, 8, and 10 days after the tumor inoculation. Previously, it was shown that the OK-432 injection on day 2 was indispensable since only a minimal antitumor effect was obtained when an inflammation-inducing agent such as thioglycolate instead of OK-432 was injected on day 2, followed by four OK-432 injections on days 4, 6, 8 and 10. In the present study, the injection of OK-432 on day 2 and a subsequent injection of either IL-2 or IFN-gamma on day 4 or 6 showed a significant antitumor effect, achieving a complete cure in approximately 50% of mice treated, although none of the mice could be cured by a single injection of either OK-432, IL-2, or IFN-gamma on day 2. Interestingly, however, the mice treated with an injection of a lymphokine (IL-2 or IFN-gamma) on day 2 followed by OK-432 on day 4 were not cured either. Peritoneal cells on day 12 in mice treated with OK-432 and either of the lymphokines contained pantropic killer cells, which were Thy-1+ and asialo GM1+ (AsGM1+). Moreover, the antitumor effect of the combined treatment was abolished when mice were pre-treated with anti-AsGM1. No significant antitumor effect was observed in athymic nu/nu mice. Together with our previous findings, these results indicate that lymphokines induced by OK-432 administration may account for some of its therapeutic effects and that these lymphokines may also facilitate the subsequent induction of specific killer cells. These results warrant further investigation on possible effective therapeutic protocols with the combined use of OK-432 and lymphokines.

Topics: Animals; Cytotoxicity, Immunologic; Female; Fibrosarcoma; G(M1) Ganglioside; Glycosphingolipids; In Vitro Techniques; Interferon-gamma; Interleukin-2; Killer Cells, Natural; Lymphokines; Mice; Mice, Inbred BALB C; Picibanil; T-Lymphocytes, Cytotoxic

Intravenously or intraperitoneally administered Chromomycin A3 (CHRM), an anticancer drug, augmented natural killer (NK) activity of both spleen cells and peritoneal exudate cells in BALB/c mice. When CHRM was administered intravenously, NK activity increased to about five fold that in nontreated mice on the 3rd to the 5th day, then rapidly decreased by the 7th day. On the other hand, when CHRM was administered by the intraperitoneal route, a peak of increased NK activity was observed on 5th to 7th day followed by a more gentle decrease. Augmentation of NK activity by CHRM was enhanced by additional administration of Interferon- gamma (IFN-gamma). Experimental evidence that NK activity could be augmented by CHRM in various strains of mice, independent of H-2 haplotype, suggested that involvement of genetic control within class I region of major histocompatibility complex could be excluded. When BALB/c mice inoculated subcutaneously with Meth A cells were treated with i.p. injection of CHRM, or CHRM in combination with IFN-gamma, the growth of the tumor cells was inhibited, indicating in vivo significance for the increased NK activity. Since this inhibitory effect was decreased by the injection of anti Asialo GM1 antibody (alpha-ASGM1), the effector cells presumably exerting killing activity against Meth A cells were concluded to be Asialo GM1 antigen positive.

Topics: Animals; Ascitic Fluid; Autoradiography; Cells, Cultured; Chromomycin A3; Fibrosarcoma; G(M1) Ganglioside; Genes, MHC Class I; Glycosphingolipids; Interferon-gamma; Killer Cells, Natural; Male; Mice; Mice, Inbred Strains; Neoplasm Transplantation; Spleen

The present study examines clonal variations in NK sensitivity in a methylcholanthrene-induced fibrosarcoma. Previous studies of clones from this tumor have shown considerable heterogeneity in H-2 expression, and an association between deleted or low levels of class-I products and increased tumorigenicity after subcutaneous implantation in immunocompetent syngeneic mice. Here, fibrosarcoma clones with no or low expression of MHC-class-I products were found to be sensitive to NK-mediated lysis, while clones with high levels of MHC-class-I expression were relatively resistant. One H-2+ (G2) and one H-2- (B9) clone were chosen for more detailed studies. Cold-target competition assays and conjugate cytotoxicity assays in agarose showed that splenic effector cells bound equally well to the H-2+ and H-2- tumor clone, although only the latter was sensitive to NK cell lysis. Treatment with 50 U/ml of rIFN-gamma for 48 hr increased the levels of H-2 expression and made both clones more resistant to NK-mediated lysis. In vivo studies with radiolabelled tumor cells showed that cells from the H-2+ clone survived better than cells from the H-2- clone in the pulmonary capillary bed after i.v. inoculation. This difference disappeared in mice treated with anti-asialo GM1 serum, known to deplete NK cell activity.

Topics: Animals; Cell Line; Cytotoxicity Tests, Immunologic; Fibrosarcoma; G(M1) Ganglioside; Genes, MHC Class I; Glycosphingolipids; H-2 Antigens; Immune Sera; Interferon-gamma; Killer Cells, Natural; Lung; Methylcholanthrene; Mice; Mice, Inbred BALB C; Tumor Cells, Cultured; Tumor Stem Cell Assay

Treatment of C57BL/6J mice with poly-I:C or antibodies to asialo-GM1 enhances and depresses respectively natural killer (NK) cell activity while inversely altering lung metastasis, suggesting a critical role for these cells in controlling tumor formation. We assessed the effect of these treatments on antitumor activity mediated by macrophage (M phi) populations likely to be important in lung metastasis. Alveolar and lung interstitial M phi were asialo-GM1 positive (98%) and were sensitive to in vitro treatment with the antibody plus complement; however, treatment of mice with antibodies to asialo-GM1 failed to alter their tumoricidal activity in vitro. Few blood monocytes (4%) or spleen M phi (2%) were asialo-GM1 positive and their antitumor activity was similarly unaffected. In contrast, however, this same in vivo treatment resulted in a 14-fold increase in lung metastasis. Intraperitoneal injection of poly-I:C greatly reduced metastasis formation but also failed to significantly affect in vitro cytolytic activity of the M phi populations. These findings suggest that the major metastasis altering effects of these agents result from modulation of NK rather than M phi function.

Topics: Animals; Antibodies; Complement System Proteins; Cytotoxicity, Immunologic; Female; Fibrosarcoma; G(M1) Ganglioside; Glycosphingolipids; In Vitro Techniques; Lung; Lung Neoplasms; Macrophage Activation; Macrophages; Mice; Mice, Inbred C57BL; Poly I-C

Murine fibrosarcoma cells were examined for sensitivity to killing by natural killer (NK) and natural cytotoxic lymphocytes from mouse spleens. These tumor cell lines were sensitive to killing by effector cells which were nonadherent to plastic or nylon wool, Thy-1 negative, asialo-GM1 negative, and present in the spleens of beige mice, nude mice, and A/J mice, as well as in the spleens of normal syngeneic and allogeneic control mice. This indicates that the cytotoxic effects were due to natural cytotoxic lymphocytes rather than to NK lymphocytes, T-cells, or macrophages. Although the fibrosarcoma cells were not killed in vitro by endogenous NK cells, these tumor cells were able to "cold target" compete for Yac-1 (an NK-sensitive target) killing and to bind to asialo-GM1-positive, nonadherent spleen lymphocytes in a target cell binding assay. This suggests that the fibrosarcoma cells were recognized by NK cells. In addition, these cell lines were killed in a 4-h NK cytotoxicity assay by polyinosinic-polycytidylic acid-activated effector lymphocytes. The interaction between NK cells and the murine fibrosarcoma cells may have in vivo significance. When syngeneic mice were treated with anti-asialo-GM1 serum to eliminate NK activity and then given i.v. injections of the fibrosarcoma cells, many more lung tumors developed than in control animals. The structural basis for the recognition of the murine fibrosarcoma cells by the NK effector cells is not known. However, laminin may be involved. When the fibrosarcoma cells, which have receptors for the laminin molecule, were preincubated with laminin, they were reduced in their ability to compete for the killing of Yac-1 cells by the NK effectors and had reduced capacity to bind to NK cells in a target cell binding assay.

Topics: Animals; Antibodies, Monoclonal; Cell Line; Cytotoxicity, Immunologic; Fibrosarcoma; G(M1) Ganglioside; Glycosphingolipids; Immunity, Innate; Killer Cells, Natural; Laminin; Lung Neoplasms; Mice; Poly I-C; Receptors, Immunologic; Receptors, Laminin

The usefulness of asialo GM1, a glycolipid surface marker, to define the effector cell types involved in tumor resistance in vitro and in vivo was assessed. Pretreatment of rat effector cells with anti-asialo GM1 antibody plus complement in vitro either abrogated or markedly diminished NK activity; in contrast, macrophage-type cytocidal activity was not diminished by such pretreatment. Similarly, systemic inoculation of anti-asialo GM1 antibody selectively eliminated NK activity, leaving macrophage-type tumoricidal reactivity intact. Finally, such pretreatment did not diminish host resistance in an in vivo tumor model in which the available evidence suggests a critical role for macrophages. The asialo GM1 marker may thus be useful in delimitating the tumoricidal capacity of cells exhibiting NK activity from that mediated by other cell types.

Topics: Animals; Antibodies; Cytotoxicity, Immunologic; Fibrosarcoma; G(M1) Ganglioside; Glycosphingolipids; Killer Cells, Natural; Lymphoma; Macrophages; Mice; Neoplasms, Experimental; Rats