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)

To determine whether hemopoietic cells infected with Friend polycythemia-inducing spleen focus-forming virus (SFFVp) are conserved or suppressed via natural surveillance in leukemia-resistant adult mice, we engrafted C57BL/6 recipients with isologous transgenic (donor origin marker) or natural killer (NK) cell-deficient B6 beige marrow cells exposed to SFFVp in vitro. Both groups of primary recipients were viremic and nonleukemic. Spleen cells from primary SFFVp-infected chimeras were engrafted into irradiated leukemia-susceptible secondary recipients to reveal dormant leukemia and grew as tumors of donor origin in 8 of 38 (21%) and 33 of 47 (70%) instances, respectively. Treatment of marrow donors and recipients with anti-asialo GM1 serum resulted in the depression of NK cell activity and the rapid development of dormant leukemia. We conclude that NK cells are an effective surveillance mechanism able to suppress SFFVp-induced preleukemic stem cells.
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PMID:Natural killer cell suppression of Friend virus-induced preleukemic hemopoietic stem cells. 347 19

Spleen cells from mice immune to Plasmodium berghei exhibited a significantly increased in vitro proliferative response to parasitized reticulocytes compared to spleen cells from normal mice. The specific response to malaria antigen was decreased in spleen cells from pregnant immune mice in contrast to the nonspecific response to the mitogen phytohemagglutinin. Addition of mouse serum to spleen cell cultures of immune mice depressed both the phytohemagglutinin and the specific proliferative response, whereas serum of pregnant mice exerted an even stronger inhibition than serum of nonpregnant mice. Charcoal adsorption of mouse sera for the elimination of steroid hormones removed the serum dependent immunosuppression from normal as well as pregnant serum. Corticosterone added to the spleen cell cultures depressed also the proliferative response. These findings demonstrate that the response to malaria antigen is decreased in immune mice during pregnancy. The possible effect of serum corticosterone on the depression of the immune response is discussed.
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PMID:Plasmodium berghei: reduction of the mouse's specific lymphoproliferative response in relation to corticosterone and pregnancy. 352 63

The potential of dietary glutathione to alter immune response in aging mice was studied. Four (young), 17 (mature) and 24 (old) month old C57BL/6Nia male mice were fed semi-purified, nutritionally adequate diets containing 0 (control) to 1.0% of reduced glutathione (GSH) for 4 weeks. Concanavalin A (Con A) stimulated proliferation of splenocytes was assessed by [3H]thymidine incorporation. Delayed-type hypersensitivity (DTH) to dinitrofluorobenzene (DNFB) was measured by a radioisotopic method. Spleen GSH and splenocyte thiol (-SH) levels were determined by HPLC and N-ethyl[14C]maleimide binding, respectively. In the control fed group, mature and old mice showed 67% and 72% reductions (P less than 0.05) in Con A stimulated [3H]thymidine incorporation compared to young mice. Dietary GSH supplementation partially, but significantly (P less than 0.05) reversed this age-associated decline in mature and old mice. DTH assays revealed that the in vivo T-cell-mediated immune function is depressed with age and that dietary GSH supplementation reverses this depression. Spleens from control-fed mature and old mice contained 12 and 19% less GSH, respectively, than young mice (P less than 0.05). This decline was also reversed (P less than 0.05) by dietary GSH supplementation. Splenocyte -SH content after incubation with Con A and responsiveness to this mitogen were positively correlated in old mice and were greater (P less than 0.05) in GSH supplemented animals. Thus, dietary GSH supplementation improves the splenic status of this tripeptide and enhances T-cell mediated immune responses in aging mice.
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PMID:Reversal of age-associated decline in immune responsiveness by dietary glutathione supplementation in mice. 360 48

Canine haemangiosarcoma was studied retrospectively in 31 cases recorded among 2,871 dogs presented for necropsy (1.08%). The German Shepherd breed was more frequently represented than other breeds. Affected dogs were older than 5 years (mean 9.1 years). Nineteen were males. Presenting signs often included episodic lethargy and weakness, with depression, anorexia and mucosal pallor. Spleen and lungs were the most frequently affected sites. Haematological findings in 9 dogs with splenic or hepatic haemangiosarcoma included a mild to moderate normochromic anaemia, neutrophilia, thrombocytopaenia, poikilocytosis and increased target cells. Acanthocytes occurred in 90% of cases, schizocytes in 80% and keratocytes and metarubyricytes in 70%. Fibrin split products were increased in 2 of the 3 cases in which they were measured. The changes in erythrocyte morphology are considered to be useful diagnostic features of canine haemangiosarcoma.
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PMID:Clinical and haematological features of haemangiosarcoma in dogs. 403 24

Spleen cells from CBA or congenitally athymic ("nude") mice were pretreated with various concentrations of DNP coupled to a copolymer of D-glutamic acid and D-lysine (DNP(37)-D-GL), under various conditions of time and temperature. After washing, they were then cultured for 3 days with the direct B cell immunogen, DNP coupled to Salmonella adelaide flagella (DNP-FLA). Under all circumstances tried, exposure of cells to 1 microg/ml DNP-D-GL caused a 70-100% depression in the subsequent DNP-specific PFC response, and 100 ng/ml caused a lesser but still substantial effect. At the concentrations used, DNP-D-GL did not affect irrelevant antibody responses. Though cells from nude mice responded somewhat less well to DNP-FLA than those from CBA mice, no significant difference in the reaction of the two populations to the tolerogen was noted. This demonstrates that DNP-D-GL can, as previously suspected, directly cause unresponsiveness in B lymphocytes.
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PMID:Induction of B cell tolerance in vitro to 2,4-dinitrophenyl coupled to a copolymer of D-glutamic acid and D-lysine (DNP-D-GL). 457 21

Several parameters of the cellular and humoral immune responses of chickens infected with reticuloendotheliosis virus (REV-T), an avian defective acute leukemia virus, or with its helper virus, reticuloendotheliosis-associated virus (REV-A), were evaluated. Spleen cells from chickens infected with REV-T (REV-A) or REV-A exhibited depressed mixed lymphocyte and mitogen responses in vitro. Allograft rejection was delayed by 6 to 14 days in birds infected with REV-A. The specific antitumor cell immune response was also studied by a 51Cr-release cytotoxicity assay. Lymphocytes from chickens infected with low numbers of the REV-T-transformed cells exhibited significant levels of cytolytic reactivity against the 51Cr-labeled REV-T tumor cells in vitro. The mitogen response of lymphocytes from these injected birds was similar to that of uninjected chickens. In contrast, lymphocytes from chickens injected with higher numbers of REV-T-transformed cells exhibited suppressed mitogen reactivity and failed to develop detectable levels of cytotoxic activity directed against the REV-T tumor cells. These results suggest that the general depression of cellular immune competence which occurs during REV-T (REV-A) infection could contribute to the development of this acute leukemia by inhibiting the proliferation of cytotoxic cells directed against the tumor cell antigens. The cytotoxic effect observed after the injection of chickens with non-immunosuppressive levels of REV-T-transformed cells appears to be specific for the REV-T tumor cell antigens since cells transformed by Marek's disease virus or avian erythroblastosis virus were not lysed. In marked contrast, birds whose cellular immune responses were suppressed by infection with REV-A were capable of producing a humoral immune response to viral antigens. Detectable levels of viral antibody, however, did not appear until 12 to 15 days after REV-A infection. Since REV-T (REV-A) induced an acute leukemia resulting in death within 7 to 14 days, it appears unlikely that the ability of chickens to make antiviral antibody influences the development of lethal reticuloendotheliosis.
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PMID:Specificity in the immunosuppression induced by avian reticuloendotheliosis virus. 618 91

Spleen cells obtained from ACI rats bearing a syngeneic hepatoma (9098) (TBR spleen cells) showed a strongly depressed mitogen responses to concanavalin A (Con A) and to phytohaemagglutinin-P (PHA) at various concentrations of the tested mitogens. The activity of suppressor cells in TBR spleens was demonstrated in mixtures with normal spleen cells where a marked depression of the mitogen response was observed. The properties of tumour-induced suppressor cells were adherent to plastic or nylon wool, phagocytic, and radioresistant (maybe macrophages). The Con A response of TBR spleen cells was more completely restored than was the PHA response after the removal of adherent or phagocytic cells. The suppression when TBR spleen cells (2,000 rad) were added to normal spleen cells at 0, 24, and 45 h after culture initiation was greater in the PHA response than in the Con A response. The PHA assay appeared to be more sensitive method than the Con A assay for the detection of suppressor cell activity in tumour bearing rats.
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PMID:Tumour-induced suppressor macrophages in rats: differences in their suppressive effects on the Con A and PHA responses. 623 88

Inbred RIII mice, known to be infected neonatally with murine mammary tumor virus so that females develop mammary adenocarcinoma by 12-15 months of age, were examined with regard to antisheep red blood cell antibody responses at the cellular level. Female mice, 3-11 months old, compared to male mice of the same ages had consistent and significant depression of the antibody response of their splenocytes. Furthermore, female mice with adenocarcinoma showed an even greater depression of the antibody response. Spleen sizes were consistently increased in females as compared to those of male mice throughout the first year of life. The blastogenic responsiveness of the splenocytes to the B-cell mitogen Escherichia coli lipopolysaccharide and the T-cell mitogen phytohemagglutinin-P was not significantly different between male and female mice during the same periods, although the responses of the older tumor-bearing female mice to phytohemagglutinin-P were lower than those of non-tumor-bearing female mice. A complex relationship between age, sex, and immune responsiveness was evident in these mammary tumor virus-infected mice, which made it difficult to attribute a specific immune event to emergence of the mammary adenocarcinomas in the female as compared to male mice.
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PMID:Age- and sex-related differences in antibody formation and blastogenic responsiveness of splenocytes from RIII mice developing virus-induced mammary adenocarcinoma. 627 37

Spontaneously hypertensive male and female rats (SHR) were compared with Wistar/Kyoto (W/K) controls at 15 wk and 80 wk of age. Treatment of the young and old hypertensives with thymosin, fraction 5, lowered the blood pressure within 4 wk of the start of treatment. Following 10 wk of injections, the blood pressures of the hypertensive rats remained at a depressed level for about 6 wk. The thymic hormone raised the depressed spontaneous T-cell rosette formation of the aged hypertensive rat and increased the lymph node T-cell response to the mitogens, Con A and PHA. Thymosin administration over a period of 7 wk increased the size of the aged hypertensive thymus. No similar effect was observed in the W/K. Spleen cell production of prostaglandin E (PgE) was markedly higher in the young hypertensive and immune complex deposition was found in the glomeruli and tubules of the aged SHR kidneys. Thymosin lowered the high level of PgE to normal and decreased the immune complex deposition in the kidney. IgG1 levels were considerably depressed in the SHR as compared to the W/K. Following thymosin administration levels of IgG1 increased 2-fold in both rat strains. Plaque-forming cells from the spleens of the untreated SHR were about 3-fold less than those of the age-matched W/K. Following treatment with thymosin the number of plaque-forming cells of both groups demonstrated a substantial further decrease. Spontaneous hypertension in rats is similar, in certain respects to autoimmune-like diseases in humans with a depression in T-cell activity as well as immune complex deposition; both conditions being altered by exposure to a thymic extract.
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PMID:Immune response modulation in the spontaneously hypertensive rat. 634 14

Specific pathogen-free B6D2 mice were infected intravenously with 10(8) viable BCG, M. habana or M. simiae and the level of tuberculin hypersensitivity to 2.5 micrograms PPD or cytoplasmic protein antigens (CPA) prepared from the other organisms was determined using the footpad swelling test with increasing time after infection. This was correlated with the growth or persistence of mycobacterial populations within the liver. Spleen cells were removed from these infected mice and the level of blast transformation following exposure to PHA, PPD or M. habana or M. simiae CPA was measured in vitro. Early in the mycobacterial infections (day 14) thymidine incorporation by the spleen cells was significantly enchanced followed by a profound depression in incorporation rates as the infection progressed. The mechanism of this depressed response involved the production of suppressor T cells in the spleen. In the case of the M. simiae or M. habana infection, cells capable of mediating suppression were still present even after 12 months of infection. In the BCG infection, suppressor T cells declined with time so that by 4 months incorporation rates were back to normal and suppressor cells were no longer detectable in the spleens of the infected animals.
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PMID:Development of suppressor T cells in mice heavily infected with mycobacteria. 644 70


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