Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

W/Fu rats inoculated s.c. with less than or equal to 5 x 10(7) syngeneic (C58NT)D (Gross virus-positive) lymphoma tumor cells normally develop a palpable tumor which reaches its maximum size (12 to 14 mm) at 6 to 8 days and is subsequently rejected by 10 to 12 days. However, rats previously sensitized with soluble tumor antigens from (C58NT)D cells prior to (C58NT)D tumor inoculation demonstrate a significant enhancement of tumor growth (the tumor reaches up to 26 mm and is rejected by 16 to 18 days). This enhancement persisted in antigen-treated rats that continued to receive soluble antigen after tumor inoculation. The in vivo enhancement coincided with a significant in vitro depression of cell-mediated cytotoxicity [assessed with 51Cr-labeled (C58NT)D target cells and peripheral blood leukocytes]. The observed tumor enhancement was specific, inasmuch as presensitization to either soluble tumor antigens from WR6 (Gross virus-negative) tumor, syngeneic to W/Fu rats, or to soluble antigen from W/Fu spleen cells had no enhancing effect on (C58NT)D tumor growth. Interestingly, sensitization to soluble tumor antigen alone did not elicit detectable cell-mediated immunity, cytotoxic antibody, or serum-blocking activity to the (C58NT)D tumor. We conclude that sensitization to soluble tumor antigens specifically impairs the immune apparatus normally acting in tumor rejection. This impairment appears to act primarily at the induction phase of the immune response.
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PMID:Specific enhancement of tumor growth and depression of cell-mediated immunity following sensitization to soluble tumor antigens. 5 98

Three tumor systems, including a mastocytoma, plasmacytomas, and a leukemia-lymphoma were studied for their ability to modify humoral immunity to sheep erythrocytes both in vivo and in vitro. All tumors resulted in a depression of the hemolytic antibody plaque-forming cell response in susceptible mice. These studies indicated that the mechanism(s) of suppression, although not fully defined, were different for each model system investigated.
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PMID:Tumor-induced immunosuppression. 10 6

Although elevated antibody levels to the Epstein-Barr virus (EBV) have been reported in a number of lympho-proliferative neoplasms, it has not been possible to determine whether these antibodies were the result of a specific response to an oncogenic agent (EBV), whether they were a non-specific humoral compensation for depressed cell-mediated immunity (CMI), or whether a different mechanism was responsible. We have previously shown in a group of lymphoma patients that depressed cellular immunity to a number of standard antigens (Candida, SKSD, etc.) is not associated with an increase in antibody to EBV. In this study, we tried to compare CMI to possible EBV and lymphoid cell line antigens with humoral antibody to EBV. The two basis CMI assays utilized were lymphocyte cytotoxicity (LC) and skin testing (ST) for delayed hypersensitivity. In the LC assay, an EBV-containing cell line (F265) was used as the target. Reactivity against F265 was stronger in normal individuals than in cancer patients, suggesting a relationship to general cellular immune competence. ST studies showed that membrane extracts from lymphoid cell lines derived from patients with Burkitt's lymphoma and nasopharyngeal carcinoma (NPC) were more likely to elicit a delayed hypersensitivity in lymphoma and NPC patients than cell lines derived from normal individuals. Patients with ST reactivity against the membrane preparations from the tumour-derived cell lines were as likely to have elevated EBV antibodies as patients without such reactivity. The data strongly indicated that the elevated EBV titres in lymphoma patients are not related to a specific or non-specific depression of CMI.
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PMID:Humoral and cellular immunity to EBV and lymphoid cell line antigens in human lymphoma. 19 66

The kinetics of phytohemagglutinin (PHA) response of peripheral blood lymphocytes from chickens infected with oncogenic Marek's disease (MD) virus (MDV) or nononcogenic herpesvirus of turkeys (HVT) was studied with a whole blood microassay. At about 7 days after inoculation, a depression in PHA response was observed in MDV-inoculated resistant line N or susceptible line 7(2) chickens and in HVT-inoculated line 7(2) chickens. All chickens initially regained their PHA responsiveness. Susceptible chickens that died of MD or developed MD lymphoma in later stages of virus infection showed a second severe depression in PHA response. No depression was observed in HVT-vaccinated chickens when challenged with MDV. The PHA response of MDV-inoculated chickens that survived MD, HVT-inoculated chickens, and HVT-vaccinated MDV-challenged chickens showed evidence of enhancement. The depression of PHA response was studied and was attributed to the suppressive effect of macrophages on T-cell response, a finding consistent with our previous studies on MDV suppression of PHA response.
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PMID:Suppression and enhancement of mitogen response in chickens infected with Marek's disease virus and the herpesvirus of turkeys. 21 Oct 85

The virus-associated depression of concanavalin A mitogenesis which accompanies feline leukemia virus-induced cat lymphoma was investigated by comparing lymphocyte surface receptor mobility of normal cats to that of viremic diseased animals. The mechanics of feline lymphocyte receptor mobility were studied using fluorescein-conjugated concanavalin A to quantitate lymphocyte capping. The results of a study of 21 disease-free animals showed that cat lymphocytes undergo appreciable concanavalin A capping, with a mean capping rate of 17% under conditions developed in this study. In contrast, morphologically normal peripheral blood lymphocytes of six feline leukemia virus-infected viremic cats, with or without lymphoma, exhibited a mean capping of only 7%, significantly less than that of the control animals (p less than 0.005). These findings suggest that a membrane-related lymphocyte deficiency accompanies the development of virus-induced lymphoma in the cat.
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PMID:Mobility of lymphocyte surface membrane concanavalin A receptors of normal and feline leukemia virus-infected viremic felines. 21 26

L-Asparaginase from Escherichia coli was immobilized by entrapment in a gel based on poly(2-hydroxyethyl methacrylate) with an activity as high as 730 I.U./g of dry gel. The apparent Michaelis constant for these gels was similar to that of the free enzyme. At 37 degrees C the immobilized enzyme had a half-life of more than 40 days, in vitro. The gel was freeze-dried, crushed and sieved to pass a 38 mum screen, giving a median particle size of 12 mum. C3H mice were injected intraperitoneally with 40 I.U. of L-asparaginase; the peak plasma activity after 4 hours was only 0.9 I.U. for the gel entrapped enzyme compared to a peak activity of 5.0 I.U. after 2 hours for the native L-asparaginase. Ninety percent of the plasma enzyme activity for the gel entrapped case was sedimentable at 21,000 X g, indicating a small leakage of the enzyme from the gel; the clearance for the enzyme activity in plasma had an initial half-life of 13 hours in contrast to a half-life of 2 hours for the native preparation. After intraperitineal injection of 5.0 I.U. into C3H mice, plasma L-asparagine fell to undetectable levels for 4 days and reappeared by day 8 for both the native and immobilized enzymes. Subcutaneously transplanted 6C3HED murine lymphoma was inhibited by 35, 78 and 100% after single intraperitoneal injections of immobilized L-asparaginase of 2, 4 and 8 I.U., respectively, as compared to 36, 53 and 86% for the native enzyme by the 14th day. Body weight changes after receiving immobilized L-asparaginase were essentially similar to those of animals receiving a comparable dose of native enzyme. These results indicate that while most of the immobilized L-asparaginase remains at the injection site, it produces a significant plasma L-asparagine depression and antitumor acitivity comparable to that of the native preparation without major toxicity.
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PMID:Gel entrapped L-asparaginase: kinetic behavior and antitumor activity. 24 45

Results are reported on 724 children and adolescents with acute leukemia-lymphoma. One hundred patients had immunologic marker analysis that defined the major phenotypic groups, i.e., T-cell, B-cell (Burkitt), myeloid, and the most frequent form, non-T, non-T "common" or "undifferentiated" acute leukemia. Pre-T, pre-B, and "null" leukemias are included in the latter group. Response to therapy and survival was best in non-T, non-B acute lymphocytic leukemia, intermediate in T-cell disease, and worst in B-cell (Burkitt) disease. Additional factors resulting in decreased survival include elevated peripheral leukocyte count, presence of enlarged nodes, less depression of hemoglobin and platelets, and age greater than 7 years (all associated with 'lymphomatous" disease). Other factors resulting in decreased survival include age under 3 years and depression of serum immunoglobulins. Definition of the heterogeneity of childhood leukemia-lymphoma dictates differing forms of therapy for the various types of these diseases.
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PMID:Childhood leukemia-lymphoma. Heterogeneity of phenotypes and prognoses. 29 37

The injection of a syngeneic Gross-virus-induced lymphoma into W/Fu rats induced peaks of cytotoxicity in the spleen attributable to non-T cells and T cells 3 and 10 days later, respectively. The conditions required for augmenting the cytotoxicity of the non-T cells in various lymphoid compartments (shown elsewhere to closely resemble NK cells) were analysed using the ip and iv routes of inoculation and a variety of tumour cells including those normally susceptible or resistant to lysis by NK cells in vitro. Using an ip inoculation of W/FuG-1 cells (a tumour susceptible to lysis by NK cells), a short-lived, 3-fold increase in cytotoxicity was observed in the spleen at day 3 and a 5-fold increase in the PEC at day 5. Cytotoxicity in other lymphoid organs remained unchanged. Tumours resistant to lysis by NK cells also stimulated cytotoxicity in the spleen or PEC, although the effect depended on the dose and route of inoculation used, and depression of cytotoxicity was observed under some conditions.
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PMID:Augmentation of cell-mediated cytotoxicity to a rat lymphoma. I. Stimulation of non-T-cell cytotoxicity in vivo by tumour cells. 48 65

A murine model of immune responsiveness had been adapted to study anergic conditions associated with neoplasia. Marked anergy observed in mice bearing L1210 leukemia and P-388 lymphoma is contrasted to the minimal immune depression associated with B-16 melanotic melanoma and Sarcoma 180J. The ability of N,N-bis(2-chloroethyl)-N-nitrosourea chemotherapy to reduce tumor burden without prolonged suppression of delayed cutaneous hypersensitivity is compared to the profound suppression of the cutaneous response observed with Adriamycin cytoreductive therapy. The applications of our model are discussed in relation to tumor-associated anergy, new approaches to the evaluation of pharmaceuticals, and studies of combined chemoimmunotherapy regimens.
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PMID:Delayed cutaneous hypersensitivity to oxazolone in mice with tumors. 63 44

Assays of thirteen cell lines, derived from mouse lymphomas, myelomas, myeloid tumors, and a mastocytoma, for sensitivity to growth inhibition by 1-beta-D-arabinofuranosylcytosine (ara-C) revealed a spectrum between the most and least sensitive which differed 100-fold from each other. An inverse correlation between sensitivity and cellular deoxycytidine 5'-triphosphate (dCTP) content was found, and this suggested that sensitivity of cells might be increased if the dCTP content was lowered during cell exposure to ara-C. Previous work has shown that thymidine treatment of cells lowers their dCTP content, and the effect of thymidine on the sensitivity of six of the cell lines to ara-C was therefore measured. Concentrations of thymidine below those inhibitory to cell growth by themselves caused an increase in ara-C sensitivity by up to 3-fold in 4 cell lines in which thymidine causes a depression in dCTP content but not in 2 myeloid lines in which the dCTP content was found not to be depressed by the same thymidine treatment. The results confirm an important role for dCTP in determining cellular sensitivity to ara-C. The finding that the sensitivity of 2 lymphoma cell lines to ara-C could be increased by concentrations of thymidine in the region of 10 micrometer, which are attainable clinically in humans, suggests that a combination of ara-C with thymidine might be useful in the treatment of some human tumors.
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PMID:Effect of thymidine on the sensitivity of cultured mouse tumor cells to 1-beta-D-arabinofuranosylcytosine. 76 Dec 29


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