Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immune stimulation with an agent such as dinitrochlorobenzene (DNCB) may delay chemical carcinogenesis. Dimethylbenzanthracene (DMBA) was used to chemically induce tumors in the hamster buccal pouch. Hamsters were studied for the effect of DNCB sensitization in the buccal pouch prior to or after DMBA tumor induction. At appropriate time intervals the hamsters were sacrificed and each cheek pouch was examined histologically for the development of DMBA-induced tumors and for the presence of lymphoid cells infiltrating the tumor site. The results show that DNCB immunotherapy or immunoprophylaxis prior to or following DMBA tumor induction can alter the type of tumor produced and stimulate an infiltration of lymphoid cells into the tumor area probably invoking immune defense mechanisms.
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PMID:Immunotherapy of chemically-induced tumors in the hamster cheek pouch with dinitrochlorobenzene. 10 65

The lymph nodes, thymus and Peyer's patches of DBA/2 mice bearing an experimental tumor, mastocytoma, were assessed histologically with special reference to the structure of the post-capillary venules. For each of the lymphoid organ studied, the post-capillary venule score (PCV-S) was determined on the three grades (grades 1, 2 and 3) of the venules classified according to the height of the endothelial cells. The highest scores were obtained in the lymph nodes and Peyer's patches of the control animals. The scores in these lymphoid organs of the tumor-bearing mice were statistically highly significantly lower than in the control series. The lowest scores, however, were obtained in the nodes and patches of mice bearing mastocytoma after the previous treatment with anti-theta-globulin. The scores in the thymuses did not deviate from each other in the three series of mice studied. The findings of the present work support the concept that the structural state of the post-capillary venules in the lymph nodes and Peyer's patches is an important regulator of the T-lymphocyte recirculation in these organs. On the other hand, the venules of the thymus seem to be unrelated both structurally and functionally to the post-capillary venules of the nodes and Peyer's patches, and a new name of "junctional venules" has been proposed for these low endothelium walled venules of the thymus.
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PMID:Post-capillary venules in the lymphatic tissues of mice bearing experimental neoplasia. 10 23

We present evidence for a role of I-A subregion-encoded determinants in syngeneic tumor immunity. In animals rendered immune to the S1509a fibrosarcoma, daily treatment with microliter quantities of antisera directed against Kk and I-Ak determinants expressed on lymphoid cells of host origin decreased the capacity for immune tumor rejection. Absorption studies revealed that anti-I-Ak antibody activity alone was sufficient for the manifestation of this effect. Furthermore, experiments utilizing F1 hybrids showed that an antiserum that was genetically unable to interact with H-2 determinants expressed on the tumor was equally effective in inhibiting tumor immunity. Suggestive evidence that the activity of this antiserum is related to interference with the generation of effector T cell function was provided by the observation that hyperimmune animals pretreated with an anti-Kk,I-Ak antiserum were no longer capable of adoptively transferring tumor immunity to naive recipients. Thus, it is possible to regulate the secondary immune response to tumor antigens by using antisera with specificity for I-A determinants expressed on cells or possibly on factors of the host lymphoid system.
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PMID:Regulation of immune response to tumor antigen: interference with syngeneic tumor immunity by anti-IA alloantisera. 10 99

Antigen-specific suppressor cells and suppressive extracts obtained from the thymuses of DBA/2 mice bearing small syngeneic P815 mastocytomas were compared for their immunogenetic properties and requirements. The assay for specific suppression involved the ability of either cells or extracts to inhibit the primary in vitro cytotoxic response of normal DBA/2 splenocytes to mitomycin-treated P815 cells. It was shown that pretreatment of suooressor cell populations with anti-Iad antiserum plus rabbit complement removed the suppressive activity. Similarly, absorption of the suppressor factor with anti-Iad antiserum removed the suppressive properties of the material. It was found that the suppressor cells, generated in DBA/2 tumor bearers, were capable of specifically suppressing the anti-P815 response of B6D2 F1 radiation chimeras possessing lymphoid cells of the H-2b or H-2t2 haplotype equally as well as they could suppress the response of H-2d-bearing effector cells. This indicates that the suppressor cells are not H-2 restricted with respect to K or D markers on the responder cells in this system.
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PMID:Further characterization of thymic suppressor cells and a factor that suppress the generation of cells cytotoxic for a syngeneic tumor in DBA/2 mice. 10 2

An unusual case of a light chain plasma cell myeloma is described. The disease was initially characterized by a diffuse lymphoplasmacytic bone marrow involvement, but subsequently developed widespread extramedullary metastases with anaplastic tumors in the skin which histologically resembled a "histiocytic lymphoma." Electron microscopic examination, in vitro protein synthesis of bone marrow lymphoidal cells, chemical and immunochemical studies of serum and urine proteins, and intracellular immunoglobulin study by the immunoperoxidase technique on the skin biopsy and postmortem tumor tissue demonstrated evidence for lambda light chain synthesis and secretion. These findings provide further support to the notion that the wide spectrum of diverse morphologic patterns seen in lymphoplasmacytic disorders originates from the same progenitor B-lymphoid cell. Distinguishing anaplastic variant of plasma cell myeloma from other undifferentiated neoplasms offers a challenge.
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PMID:Lymphoplasmacytic myeloma: an immunological, immunohistochemical and electron microscopic study. 11 Apr 36

Ribonucleic acid extracts of lymphoid cells from immune hosts were used to transfer in vivo and in vitro cell-mediated immune reactivity to a variety of antigens. The in vivo immune responses transferred by RNA included the delayed cutaneous hypersensitivity reaction to fungal and chemically-defined antigens and the tumor-rejection reaction to guinea pig hepatoma antigens. The in vitro immune responses transferred by RNA included macrophage migration inhibition by fungal, chemically-defined, and tumor antigens. The transfer activity of RNA preparations was contained in the 8 s to 18 s species of RNA and was sensitive to RNase but not to DNase or trypsin. Antigen was not detectable in the RNA preparations and appeared to have no role in the transfer activity. Syngeneic, allogeneic, or xenogeneic sources of RNA could transfer immune reactivity. In each system tested, the transfer of cell-mediated reactivity by RNA was specific for the antigen used to sensitize the RNA donor. The potential use of RNA-mediated transfer of immunity is discussed.
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PMID:Some perspectives on the transfer of cell-mediated immunity by immune-RNA. 11 79

A diffuse generalized lymphoma histologically classified as mixed histiocytic-lymphocytic type and associated with profound immunologie abnormalities is reported. The patient had an autoimmune hemolytic anemia, an autoimmune thrombocytopenia, polyclonally increased IgG and IgM, polyclonal secretion of kappa and lamda chains into urine, very low serum complement C3 and antibodies against glomerulus and smooth muscle. When studied with the modern surface-marker techniques, the lesion was found to be composed of entirely lymphoid cells of the B-lymphocyte series. The proper classification of this tumor could be a primitive immunoblastic sarcoma. The relationship of the present tumor to the non-neoplastic angioimmunoblastic lymphadenopathia is discussed. The necessity of applying the surface-marker techniques in the classification of malignant lymphomas is emphasized.
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PMID:A diffuse mixed histiocytic-lymphocytic lymphoma associated with immunological abnormalities. 11 43

A comparison of the growth rates of established human lymphoid and tumor cell lines was performed in nutrient medium made hyperosmolal with mannitol, NaCl, or mixtures of NaCl and KCl at a constant Na/K ratio. It was found that considerably higher osmolalities were attained with mannitol than electrolytes before a reduction in the growth rate of the culture was observed. This suggests that mannitol and electrolytes affected the growth rate through different mechanisms. Mannitol uptake was studied with two of the cell lines and both cell lines were found to be permeable to mannitol. This eventually would have eliminated the osmolality gradient between the interior of the cell and the medium, and could explain why higher osmolalities were obtained with mannitol before the growth rate was effected. In addition, initial experiments showed that these cell lines may also be able to metabolize mannitol.
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PMID:The growth response of cells in medium made hyperosmolal with electrolytes or mannitol. 12 Mar 72

Quantitative absorptions of anti-H-2 alloantisera with increasing concentrations of T cell-derived tumor cells of donor H-2 type has been found to remove antibodies to H-2K region antigens selectivelymsimilar results were obtained after absorptions with thymocytes of the donor strainl In each case residual antibodies reacting with Ir-associated B cell alloantigens (Ia antigens) were unmasked by this procedure. Antisera which initially contained comparable titers of Ia and H-2 activity were depleted of H-2 activity at absorbing cell concentrations which did not appreciably alter the Ia reactivities, indicating that Ia antigens, if expressed on these T cell populations, must have been present at very low concentrations relative to H-2D and H-2K region antigens. Further absorptions with spleen cells from cross-reactive strains demonstrated a multiplicity of shared and unique Ia specificites in these sera. The multiple Ia antigens detected appeared all to be codominantly expressed on the same subpopulation of lymphoid cells.
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PMID:Ir-associated murine alloantigens: demonstration of multiple Ia specificities in H-2 alloantisera after selective absorptions. 12 84

Lymphoid cells from normal and immunized BALB/c mice could be stimulated in vitro by syngeneic PCT contrasted with an absence of response to a number of other tumors. Maximal responses of normal cells to PCT were found to occur 5 days after the initiation of the cultures at an optimal responding:stimulation cell ratio of 1:2. MLTI activity of normal cells could not be blocked or enhanced by PCT myeloma protein products indicating that MLTI reactivity was directed against non-idiotypec cell surface determinants. Lymphoid cells from immunized mice demonstrated increased MLTI responses to cells of the immunizing tumor but not to other PCT, indicating that the post-immunization MLTI responses were primarily to individual rather than shared tumor cell surface antigens. Activity of both normal and immunized spleen cells was found to involve thymus-derived lymphocytes. The persistence of residual MLTI activity after treatment with anti-theta serum and complement, however, implicated participation of non-theta antigen-bearing cells in MLTI reactivity. From these data, we conclude that lymphoid cells from un-immunized mice are capable of T cell-dependent reactivity to syngeneic PCT-associated antigens and that elevations in these reactivities after immunization may reflect specific cellular immune responses.
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PMID:Stimulation of lymphoid cells from normal and immune mice by syngeneic BALB/c plasma cell tumors. 12 71


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