concanavalin-a and Rhabdomyosarcoma

Methylcholanthrene-induced murine rhabdomyosarcomas and skeletal muscle of 10 and 18 d old murine embryos were investigated by lectin histochemistry (WGA, RCA-I, LCA, Con-A, PSA, UEA-I, PNA) and by immunohistochemistry (vimentin, desmin, myoglobulin). In rhabdomyosarcomas as well as in the developing skeletal muscle a clear trend was visible. A decrease of vimentin positivity and an increase of desmin positivity were associated with a diminution of binding sites for WGA, RCA, and LCA. No binding moieties for these lectin could be demonstrated in myoglobin positive normal and neoplastic rhabdomyomatous cells at all. The homologous expression or absence of markers reflected the cellular variability in rhabdomyosarcomas and may be explained as a phenomenon of different tumor cell maturation. The results show that rhabdomyosarcomatous cells are imitating the normal skeletal muscle development.

Topics: Animals; Binding Sites; Concanavalin A; Desmin; Female; Histocytochemistry; Immunohistochemistry; Lectins; Male; Methylcholanthrene; Mice; Muscles; Myoglobin; Plant Lectins; Rhabdomyosarcoma; Vimentin; Wheat Germ Agglutinins

Considerable evidence documents the importance of co-factors, including the immune response, in expression of oncogenicity of tumour viruses. To determine whether a common protozoal infection that can depress lymphocyte function alters manifestations of oncogenic virus infection, a mouse model of Toxoplasma infection with depressed T lymphocyte function was developed. In this model, Toxoplasma depressed blastogenic transformation to the T-cell mitogen Concanavalin A and primary antibody response to sheep red blood cells which requires T cell help. Uninfected and Toxoplasma-infected mice were then infected with Moloney leukaemia or Moloney sarcoma viruses and development of lymphoma and sarcoma were evaluated. Toxoplasma infection, which induced depression of T-cell function, decreased the incidence of Moloney sarcoma virus induced rhabdomyosarcomas but did not alter progression or regression of tumour in those mice that developed tumour. Conjoint infection with Toxoplasma and Moloney leukaemia virus did not increase incidence of lymphoma when compared with incidence of lymphoma in mice infected with Moloney leukaemia virus alone.

Topics: Animals; Antibody Formation; Concanavalin A; Female; Leukemia, Experimental; Lymphocyte Activation; Lymphoma; Mice; Mice, Inbred BALB C; Moloney murine leukemia virus; Moloney murine sarcoma virus; Rhabdomyosarcoma; Sarcoma, Experimental; T-Lymphocytes; T-Lymphocytes, Helper-Inducer; Thymus Gland; Toxoplasmosis

A relatively simple and easily reproducible method is presented for testing the activity of tumour-associated suppressor cells in the syngeneic system. It includes adoptive transfer and radioactive assay of the inhibition degree of the specific proliferative response to tumour cells of syngeneic recipients.

Topics: Animals; Cell Division; Concanavalin A; Immunization, Passive; Lymph Nodes; Lymphocyte Transfusion; Lymphocytes; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Neoplasm Transplantation; Rhabdomyosarcoma; Spleen; T-Lymphocytes, Regulatory; Transplantation, Isogeneic

This preliminary investigation was concerned with the hypothesis that macrophages associated with tumors induced to regress temporarily by the action of cyclophosphamide (CY) have the capacity to suppress local T- or B lymphocyte responses which otherwise might cause permanent regression. Cultures of adherent cells, predominantly tumor-associated macrophages ( TAMs ), isolated from two C57BL/6J (B6) sarcomas, MCA/76-9 and 76-64, after various periods of tumor growth or after CY injection (240 mg/kg) were shown to suppress or enhance the response of 10(6) B6 normal spleen cells to stimulation by concanavalin-A (Con A) or lipopolysaccharide (LPS). At any given time point, the extent of suppression or enhancement induced by adherent cells isolated from tumors after CY injection was similar to that induced by cells from progressing tumors and appeared to be more dependent on the time after the initial injection of tumor cells than on drug treatment per se. Thus, adherent cells suppressed Con A and LPS responses when they were isolated either from small (0.5 g) or large (greater than 1.5 g) progressing tumors or from tumors 4-9 days after CY injection. However, during the logarithmic phase of tumor growth or within 4 days of injecting CY, adherent cells enhanced spleen cell mitogenic responses, particularly to LPS stimulation. The cultures of putative TAMs isolated at the various time points were seen to contain varying proportions of polymorphonuclear cells (PMNs), the proportions coinciding with the period of reduced spleen cell mitogenic responses. Cultures prepared from small or large progressing tumors contained about 10% or 20-30% PMNs, respectively, while those from tumors tested during the log phase contained less than 5% PMNs. Cultures from tumors removed within 4 days of injecting CY contained less than 5% PMNs while those prepared from tumors tested at later times contained as high as 25% PMNs by 9 days after CY injection. A comparison of peritoneal PMNs and macrophages from non-tumor-bearing mice in terms of their ability to influence mitogenesis indicated that PMNs at high ratios (1 PMN:2 spleen cells) could suppress responses directly. Lower ratios had either small suppressive effects or no effects but in no case was enhancement of responses seen. Peritoneal macrophages suppressed responses at a ratio of 1 macrophage:10 spleen cells but enhanced responses at ratios of 1 macrophage:100 or 1,000 spleen cells. The overall data indicated that the mic

Topics: Animals; B-Lymphocytes; Concanavalin A; Cyclophosphamide; Macrophages; Male; Mice; Mice, Inbred C57BL; Mitogens; Neoplasms, Experimental; Rhabdomyosarcoma; T-Lymphocytes

Changes in the immune competence and levels of suppressore elements were assessed by mitogen stimulation and in vitro antibody production, after resection of a transplantable sarcoma. Spleen cells from tumour-resected animals were found to have depressed responses to conA as well as to the antigens SRBC and DNP-LPS. This inability to respond was gradually overcome and, by Day 21 after resection, spleen cell competence had returned to normal levels. Suppressor cells isolated from the spleens of tumour-resected animals were capable of suppressing the conA response and PFC response of normal syngeneic spleen cells in vitro. The ability to suppress the conA response of normal cells disappeared by Day 1 after resection, while the ability to suppress the anti-SRBC and anti-DNP PFC response of normal cells disappeared by Day 8 and Day 14 respectively. Serum from tumour-resected mice was also found to be suppressive to the conA response of normal spleen cells. The inhibitory material responsible for suppression eluted with the Ig-containing fraction on Sephadex G-150. This inhibitory material gradually disappeared from the serum of tumour-resected mice and was no longer apparent by Day 14. Therefore, it appeared that the return of normal lymphocyte function after tumour-resection was concomitant with the disappearance of splenic suppressor cells and suppressive serum factor.

Topics: Animals; Antibody Formation; Concanavalin A; Female; Immunity; Immunity, Cellular; Lymphocyte Activation; Mice; Mice, Inbred DBA; Rhabdomyosarcoma; Sarcoma, Experimental; Spleen; T-Lymphocytes; Time Factors

Sera from mice with large tumours from a variety of tissue types and sources have been shown to contain substances capable of suppressing the proliferative response of normal mouse lymphocytes to concanavalin A (Con A), bacterial endotoxin (LPS) and allogeneic cells. The present paper deals with studies on the nature of these inhibitory materials using mainly a methylcholanthrene-induced rhabdomyosarcoma in DBA/2J mice. It was found that a material responsible for inhibition of the Con A response eluted with immunoglobulins on Sephadex G-150 and eluted with monomeric immunoglobulin on Sephadex G-200. The component of tumour-bearer serum responsible for the suppression of the LPS response of normal lymphocytes eluted from Sephadex G-150 with the alpha and beta globulins and albumin (molecular weight less than 150,000). The immunoglobulin-containing serum fraction from tumour-bearing animals inhibited the mixed lymphocyte response, Con A response, and specific immune response to purified protein derivative (PPD) in allogeneic cell systems. It also inhibited the in vitro primary response of mouse cells to sheep red blood cells, and, to a lesser extent, the response to a T cell-independent antigen (DNP-dextran). The inhibitory activity continued to elute with monomeric IgG on Sephadex G-200 when columns were run in 1640 medium and adjusted to pH 2-5, indicating that an acid dissociable complex was not responsible for inhibitory activity. Inhibitor activity could be removed by absorption on immuno-adsorbents containing goat anti-mouse immuno-globulin, and could be recovered by acid elution from the absorbent. Inhibitor activity was not removed by immunoadsorption on columns prepared with antisera to chicken immunoglobulin.

Topics: Adsorption; Animals; Antibody Formation; Chromatography, Gel; Concanavalin A; Immunoglobulin G; In Vitro Techniques; Lipopolysaccharides; Lymphocyte Culture Test, Mixed; Mice; Mice, Inbred DBA; Molecular Weight; Neoplasms, Experimental; Rhabdomyosarcoma; T-Lymphocytes; Tuberculin

The mitogens concanavalin A (Con A) and bacterial lipopolysaccharide (LPS) stimulated normal spleen cells of DBA/2J, CBA/J, and BALB/c mice about equally in the presence of either isologous or homologous serum. This system revealed that sera from mice with five different methylcholanthrene-induced rhabdomyosarcomas inhibited mitogen stimulation of normal spleen cells. Sera from mice with a mammaryadenocarcinoma and spontaneous rhabdomyosarcoma were similarly suppressive. In contrast, sera from mice with melanoma were not inhibitory and often enhanced stimulation. Sera from tumor-bearing animals had the same effects both qualitatively and quantitatively on cells from the strain carrying the tumor and on cells from the other two strains. The mixed lymphocyte response of CBA/J times BALB/c spleen cells was affected exactly as were the responses to mitogen by the various sera. Stimulation by mitogen of mouse lymph-node cells and spleen cells with macrophages removed, as well as that of guinea pig spleen cells, was also inhibited by sera from mice with rhabdomyosarcoma and mammary adenocarcinoma.

Topics: Adenocarcinoma; Animals; Blood; Concanavalin A; Guinea Pigs; Lipopolysaccharides; Lymph Nodes; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Lymphocytes; Mammary Neoplasms, Experimental; Melanoma; Methylcholanthrene; Mice; Mice, Inbred BALB C; Mice, Inbred CBA; Mice, Inbred DBA; Mitogens; Neoplasms, Experimental; Polysaccharides, Bacterial; Rhabdomyosarcoma; Sarcoma, Experimental; Spleen

Blocking factors are small polypeptide molecules that may appear in the serum of patients with cancer. These factors block the transformation of lymphocytes in culture to nonspecific mitogens such as phytohemagglutinin or concanavalin A and, therefore, may reflect changes in the immunocompetence of the patient. Blocking factors were monitored during the clinical course of thirty-five patients with cancer. These factors did not develop in patients with response to therapy whereas they did develop in patients without response. A third group of patients without response to therapy after a previous remission showed an absence of lymphocyte responsiveness in culture that was not due to blocking factors, suggesting that immune clone consumption had occurred. Dermal responsiveness to tumor antigen correlated with a favorable clinical course and was usually absent when serum blocking factors were present.

Topics: Antibody Formation; Antigens, Neoplasm; Carcinoma, Squamous Cell; Concanavalin A; Humans; Immunotherapy; Lectins; Leiomyosarcoma; Lymphocyte Activation; Lymphocytes; Melanoma; Neoplasms; Osteosarcoma; Peptides; Pharyngeal Neoplasms; Rhabdomyosarcoma; Skin Tests

Spleen cells from mice immunized against a methylcholanthrene induced rhabdomyosarcoma inhibited tumour cell colony formation in vitro and prevented tumour development in vivo in an adoptive transfer test. Treatment of the immune spleen cells with anti-mouse immunoglobulin serum or passage through a nylon wool column, both of which reduced the percentage of immunoglobulin bearing cells in the population to less than 3-4%, did not alter their anti-tumour effects. In contrast, treatment of the spleen cells with anti-BAomicron serum abolished their anti-tumour effects both in vitro and in vivo. These results indicate that T cells are the mediators of tumour immunity in this chemically induced tumour system.

Topics: Animals; B-Lymphocytes; Concanavalin A; Female; Immunity, Cellular; Immunization, Passive; Lipopolysaccharides; Methylcholanthrene; Mice; Mice, Inbred DBA; Neoplasms, Experimental; Rhabdomyosarcoma; Spleen; T-Lymphocytes

Sera from mice with transplanted 3-methylcholanthrene (MCA)-induced tumors inhibited the proliferative response of normal mouse lymphocytes to mitogens and allogeneic cells. The sera were not toxic to these cells and did not inhibit mitogen responses by an increased binding of mitogen to serum components. The sera could have prevented the initiation of the proliferative response or could have inhibited cells already proliferating. The uptake of 3H-uridine, an event preceding DNA synthesis, was also suppressed. The sera had no effect on proliferation of a normal tissue culture line or an allogeneic tumor cell line induced by MCA. However, sera from tumor-bearing mice slowed growth of the autochthonous tumor cells and allogeneic lymphoma cells but did not completely block their proliferation. Exposure of lymphoid cells to the sera for a period as brief as 1 hour markedly decreased the ability of cells to respond subsequently to mitogens, and washing of the cells did not restore that ability. The inhibitory activity of the sera was only partially removed by absorption with lymphoid cells or cell lines.

Topics: Animals; Cell Line; Concanavalin A; Lipopolysaccharides; Lymphocyte Activation; Lymphocytes; Lymphoma; Mice; Mice, Inbred Strains; Neoplasms, Experimental; Rhabdomyosarcoma; Thymidine; Uridine

Topics: Animals; Concanavalin A; Female; Immunosuppression Therapy; Lipopolysaccharides; Lymphocyte Activation; Mice; Mitogens; Rhabdomyosarcoma; Sarcoma, Experimental; Spleen; Time Factors

Topics: Agglutination; Animals; Cats; Cell Line; Cell Transformation, Neoplastic; Cells, Cultured; Centrifugation, Density Gradient; Clone Cells; Concanavalin A; Cricetinae; Embryo, Mammalian; Gammaretrovirus; Humans; Leukemia Virus, Murine; Mice; Moloney murine leukemia virus; Rats; Rhabdomyosarcoma; RNA Viruses; Thymus Gland; Tritium; Uridine; Viral Plaque Assay; Virus Replication