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)

The question of increased tumor cell dissemination after surgical stress was addressed in the model system of the spontaneously metastasizing rat adenocarcinoma BSp73ASML, wherein amputation of the hind leg 7 days after intrafootpad implantation of tumor cells cured the animals, while surgical stress by laparotomy 2 days prior to amputation resulted in lung metastases in 80% of rats. A detailed in vitro analysis of natural killer (NK) and macrophage (Mo) activity in different lymphatic compartments revealed the following impacts of surgery: splenic NK cells displayed unaltered activity. Yet, there was a considerable decrease in the number of lymphoid cells during the first 4 days after surgery, being followed by an overshooting repopulation. In the peripheral blood, activity levels of NK cells dropped significantly during the first 24 h after surgery; later on, NK cells appeared activated with an over 2-fold increase in lytic units (LU), 4 days after surgery, NK activity had returned towards normal levels. Most dramatic changes were observed in the peritoneal cavity, being directly involved in the surgical intervention. Six hours after surgery the peritoneal cavity was nearly depleted of NK cells and Mo, the few remaining cells being highly activated. Within 2 days the peritoneal cavity was repopulated with a 3-4 fold excess of lymphoid cells and Mo, but the repopulating cells were extremely low in lytic activity. It is concluded that depression of nonadaptive immunity after surgical stress is mainly due to traffic and repopulation with immature cells, i.e. there was no indication of suppressor cell activity. This was confirmed by a combined treatment consisting in a systemic application of Corynebacterium parvum 2 days before surgery and a local application of C. parvum after surgery, which counter-balanced the stress-induced depression of NK and Mo activity. Accelerated and increased metastatic spread could be prevented concomitantly.
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PMID:Depression of nonadaptive immunity after surgical stress: influence on metastatic spread. 270

The present study evaluated whether protein kinase C (PKC) activation was involved in the lymphocytosis promoting properties of pertussis toxin (Ptx). The exposure of mouse lymphocytes to phorbol esters (as a means to selectively activate PKC) caused a depression in their subsequent capacity to localize into lymph nodes and Peyer's patches in vivo. This pattern of inhibition was quite similar to that observed with lymphocytes treated with Ptx. The mechanisms responsible for the observed decreases in localization to lymphoid organs caused by these two agents, however, appeared to be distinct. Exposure of lymphocytes to PMA was followed by a time and dosage-dependent decrease in the surface density of MEL-14 defined homing receptors. Ptx-treated lymphocytes retained normal density of this homing receptor. Consequently, PMA-treated lymphocytes lost their capacity to bind to high-endothelial venules in in vitro lymph node binding assays while Ptx-treated cells retained normal high-endothelial venule binding potential. We conclude from this study that: 1) the activation of PKC in lymphocytes by PMA can alter their recirculation properties via mechanisms that diminish their expression of surface receptors which support extravasation into lymph node and mucosal lymphoid tissues, and 2) even though Ptx has been reported to elevate the rate of inositol phosphate turnover in lymphocytes, the loss of extravasation potential of Ptx-treated lymphocytes is not mediated via the modification of surface homing receptors as observed in cells exposed to the known PKC activator, PMA.
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PMID:Molecular mechanisms of lymphocyte extravasation. III. The loss of lymphocyte extravasation potential induced by pertussis toxin is not mediated via the activation of protein kinase C. 273 69

Forty-six bone marrow biopsies from twelve hairy cell leukemia (HCL) patients, treated with either interferon(IFN)-alpha-2 (n = 8) or 2'deoxycoformycin(DCF) (n = 4), were examined using cryostat sections and an immunoperoxidase technique. Using this sensitive method we were able to demonstrate residual hairy cell (HC) infiltration in five cases, in which evaluation with conventional staining techniques on plastic embedded biopsies revealed complete remission. The amount of HCs in these five samples ranged from 1 to 7% (mean: 3%) of bone marrow cells. Consecutive biopsies in individual HCL patients revealed no changes of the immunological phenotype (CD19, CD22, CD25, CD10, CD11c, FMC7, HLA-DR, surface immunoglobulins) during IFN and DCF treatment. Within the infiltrated bone marrow a considerable number of "reactive" T lymphocytes was identified with prevalence of the T-helper (CD4+) subtype in untreated cases, whereas T-suppressor/cytotoxic (CD8+) cells were within the normal range. IFN treatment resulted in a reduction of CD4+ T lymphocytes (p less than 0.02). Minor alterations of CD8+ T lymphocytes and NK cells (HNK-1 + lymphoid cells) were found in bone marrow during IFN treatment. In DCF-treated patients bone marrow T lymphocytes were markedly reduced below the values of normal bone marrow. This DCF-induced T-cell depression might be related to the clinical observation of persistent cellular immune dysfunctions in HCL patients despite a DCF-induced remission.
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PMID:Immunohistological assessment of bone marrow biopsies from patients with hairy cell leukemia: changes following treatment with alpha-2-interferon and deoxycoformycin. 278 47

In this study, we tried to establish a relationship between the immunopotentiating effects and the antioxidant activity of the immunostimulating compound, diethyldithiocarbamate (DDC). We studied the effects of DDC treatment on enriched T and B murine spleen lymphocytes in an in vivo-ex vivo model of O2-induced immune depression. Female C57B1/6 mice were injected subcutaneously with a single dose of DDC (125 mg.kg-1). Eight days after DDC injection, we evaluated, in vitro, the concanavalin A response of the T cell fraction and the LPS response of the B cell fraction, under standard (air--5% CO2) and hyperoxic (60% O2--5% CO2) culture conditions. The results show that after a lag period, DDC is able to enhance the mitogenic response of T and B murine lymphocytes under standard culture conditions to restore the ConA response and to partially restore the LPS response under hyperoxic conditions. The results of this study suggest that the immunostimulatory effects of DDC could be related to the antioxidant activity of this compound on the lymphoid cellular metabolism. This activity apparently affects both T and B lymphocytes.
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PMID:In vitro O2-induced depression of T and B lymphocyte activation is reversed by diethyldithiocarbamate (DDC) treatment. 284 Dec 40

Retroviruses cause cancer by several different mechanisms including addition of an oncogene, addition of a modified viral glycoprotein, activation of a proto-oncogene, transactivation of a proto-oncogene, immune depression, and stimulation of lymphoid cell proliferation. Both the evolution of oncogenes and tumor induction by most retroviruses is multi-step. Study of the evolution of a particular oncogene, v-rel, indicates that this evolution could not have been selection-driven, but that it resulted from the high rate of mutation in retroviruses replication, that is, it was mutation-driven. Argument is made that much other cancer is also mutation-driven.
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PMID:Retroviruses and the genetics of cancer. 284 85

The clinical signs, hematologic changes, serum and fecal virus titers, specific antibody production and the occurrence of histologic lesions were studied in 22 nine-week-old seronegative beagle dogs inoculated by the oral and intravenous route with canine parvovirus. Approximately 30% of the dogs had clinical signs of pyrexia, depression, vomiting, and diarrhea irrespective of the route of inoculation. Events in the dogs inoculated intravenously preceded those in dogs inoculated orally by approximately two days. Only one dog died. Lymphopenia was the most consistent hematologic change. Viremia always preceded the initiation of fecal virus shedding. Viral titers in the serum and feces were significantly greater in symptomatic dogs compared to asymptomatic dogs. Termination of the plasma viremia coincided with the onset of the humoral immune response, but viremia persisted one day longer in symptomatic dogs. The severity of lymphoid tissue and intestinal infection, assessed by tissue immunofluorescence and histology, was also greater in symptomatic dogs. The severity of intestinal disease was highly correlated with the magnitude and duration of viremia.
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PMID:Pathogenesis of canine parvovirus enteritis: the importance of viremia. 298 78

The role of long-time immune suppression in carcinogenesis induced by the long-lived internal emitter 90Sr, is investigated in an ongoing study. The experimental design is based on the assumption that impaired immune responsiveness, by other means than 90Sr, might increase the neoplastic response in exposed individuals, and thus reflect a protective function, if existing. Intercomparison is made of the tumour yield in mice exposed to different single doses of 90Sr and simultaneously subjected or not to long-term immune suppression by adult thymectomy (ATx) and/or antilymphocyteglobulin (ALG) treatment. Information on the general condition and responsiveness of the immune system, in the respective models, during tumour expectancy time, is essential for a conclusive evaluation of the results. To meet these demands the present paper reports on histopathologic alterations in immune organs and changes in white blood cell counts, induced by the different combinations of 90Sr, ATx and ALG treatment. The results confirm the prediction, that ATx + ALG is an efficient and, with respect to the purpose of the study, suitable treatment for additive long-term depression of the immune system in 90Sr irradiated mice, evidenced in particular by increased depletion of monomorphonuclear cells (MNC) in lymphoid organs and peripheral blood. Subsequent reports will deal with functional immune parameters.
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PMID:Influence of 90Sr, adult thymectomy and antilymphocyteglobulin on haematopoietic tissues and peripheral blood leucocytes in CBA mice. 301 60

Antigen antibody complexes are suspected to play a role in the pathogenesis of some of the lesions that result from schistosomiasis. To examine the effect of immune complexes on the immune system of mice experimentally infected with Schistosoma mansoni, we measured antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-mediated serum hemolysis in normal and infected animals. ADCC activity in infected mice was depressed compared to control mice. However, preincubation of spleen cells for 24 h in medium followed by washing restored ADCC activity. This suggested that a soluble factor(s), presumably immune complexes, was bound to the Fc receptors with resultant block in ADCC activity and this was removed in vitro during the 24-hour preincubation. Furthermore, the complement activity of mouse serum was markedly depressed in mice infected for 3 or 6 weeks. Again, the presence of immune complexes could explain this depression since immune complexes bind complement. We attempted to confirm and extend these findings with an immunoperoxidase-staining technique using antibody to S. mansoni antigen. Most of the granuloma formations identified in portal tracts and intestinal mucosa were composed of macrophages and epithelial cells surrounding a central nidus of schistosome egg. In addition, schistosome antigen was seen diffusely bound to some of the lymphoid elements in the lamina propria and many of these cells appeared plasmacytoid. Furthermore, large amounts of schistosome antigen were sequestered in the medullary cords of the mesenteric lymph nodes and in the Billroth cords of the spleen. This suggests that the antigen is conveyed to the lymph nodes and the spleen through the systemic circulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Parasitic modulation of host immune mechanisms in schistosomiasis. 311 52

Beginning about 5 weeks after infection, C57BL/6J mice infected with Schistosoma japonicum developed granulomas around parasite eggs trapped in the liver. These granulomas attained peak size about 9 weeks after infection and then spontaneously regressed. This regression was also induced by the injection of serum immunoglobulin G1 but not lymphoid cells from chronically infected mice, but it was conceivable that lymphoid cells from mice infected for 10 weeks could also induce regression. We investigated the possibility of cellular suppression of egg antigen-induced immune responses by coculturing spleen cells from 5- to 6-week-infected mice with spleen cells from mice infected for 10 weeks or longer. Mitomycin C-resistant Thy 1.2+, Lyt 2.2+ splenic T cells from mice infected for 10 to 25 weeks consistently suppressed the egg antigen-stimulated proliferation of spleen cells from 5- to 6-week-infected mice. Suppression was dependent upon specific antigen and optimal concentrations of egg antigen and T suppressor cells. Once induced, the suppressor cells were nonspecific. Cultured T cells from uninfected mice also occasionally suppressed the acute spleen cell proliferative response, but these cells were mitomycin C sensitive. These in vitro observations suggest that granulomatous inflammation in vivo may also be down regulated by suppressor T cells and that these cells may also be implicated in the nonspecific depression of cellular and humoral responses to antigens observed during the course of this infection.
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PMID:Regulation of egg antigen-induced in vitro proliferative response by splenic suppressor T cells in murine Schistosoma japonicum infection. 316 31

From May 1980 through July 1986, 26 patients with severe aplastic anemia, sensitized with multiple transfusions of blood products, were treated on either of two immunosuppressive regimens in preparation for bone marrow transplantation from a matched donor. There were 10 patients treated with total body irradiation (TBI), 200 cGy/fraction X 4 daily fractions (800 cGy total dose), followed by cyclophosphamide, 60 mg/kg/d X 2 d. An additional 16 patients were treated with total lymphoid irradiation (TLI) [or, if they were infants, a modified TLI or thoracoabdominal irradiation (TAI)], 100 cGy/fraction, 3 fractions/d X 2 d (600 cGy total dose), followed by cyclophosphamide, 40 mg/kg/d X 4 d. The extent of immunosuppression was similar in both groups as measured by peripheral blood lymphocyte depression at the completion of the course of irradiation (5% of initial concentration for TBI and 24% for TLI), neutrophil engraftment (10/10 for TBI and 15/16 for TLI), and time to neutrophil engraftment (median of 22 d for TBI and 17 d for TLI). Marrow and peripheral blood cytogenetic analysis for assessment of percent donor cells was also compared in those patients in whom it was available. 2/2 patients studied with TBI had 100% donor cells, whereas 6/11 with TLI had 100% donor cells. Of the five who did not, three were stable mixed chimeras with greater than or equal to 70% donor cells, one became a mixed chimera with about 50% donor cells, but became aplastic again after Cyclosporine A cessation 5 mo post-transplant, and the fifth reverted to all host cells by d. 18 post-transplant. Overall actuarial survival at 2 years was 56% in the TLI group compared with 30% in the TBI group although this was not statistically significant. No survival decrement has been seen after 2 years in either group. There was less long-term morbidity in the TLI group compared with TBI although the numbers of surviving patients are small. With no difference in engraftment or survival, it is suggested that, for sensitized severe aplastic anemia patients, who are to receive a non-T cell-depleted marrow from a matched donor, prudent cytoreduction should include a fractionated, moderate dose irradiation regimen with maximum organ sparing, that is either TLI or TAI.
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PMID:Immunosuppression prior to marrow transplantation for sensitized aplastic anemia patients: comparison of TLI with TBI. 329 Jan 68


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