Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have systematically analysed the various parameters of rat mixed lymphocyte culture (MLC), aiming at defining optimal conditions in analytical (micro) MLC and at the production of maximal numbers of blast cells in preparative (maxi) MLC. Treatment of both responder and stimulator cells, or at least the responder cells, with N-acyl-neuraminidase allowed a good and reproducible analytical MLC response. Responses with a maximal resolution between the stimulated versus nonstimulated control cultures were obtained in the presence of rat sera, BN serum being superior to Lewis and AO serum in supporting the response. Rat sera derived from DA and HO strains, fetal calf serum, and human serum were not good. Spleen cells, lymph node cells, and density-separated blood leucocytes were good responders, and spleen cells were good stimulators, provided the spleen cells were prepurified from most of the phagocytic cells with iron powder plus magnet. Similar culture conditions were applicable also for the maxi-MLC assay. The number of blast cells generated from a single spleen could, however, be increased by a factor of 10, if the responder cell donor was primed intravenously with 10 x 10(6) stimulator-strain spleen cells 72 h before being killed. The responses both in the non-primed and in the primed cultures were specific, since the background stimulation was negligible and the cytotoxic effect by the primed cells in the cell-mediated lysis assay was immunologically specific.
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PMID:Rat mixed lymphocyte culture: optimization of culture conditions. 16 16

The early events in lipopolysaccharide (LPS)-induced B-cell activation were investigated by studying the binding of 14C-labeled LPS to murine lymphocytes in vitro. In these studies we utilized intrinsically labeled 14C-labeled LPS from Salmonella minnesota or the 14C-labeled glycolipid derived from the Re mutant of S. minnesota (R595). Bone marrow-derived (B) lymphocytes bound more LPS than did thymus-derived (T) lymphocytes. Binding of LPS to murine spleen lymphocytes from strain C3H/HeN was compared with the binding to spleen lymphocytes from strain C3H/HeJ, a strain resistant to certain biological activities of LPS including mitogenesis. Spleen cells from both strains bound LPS equally well, suggesting that unresponsiveness of C3H/HeJ mice to LPS is due to factors other than a defect in binding of LPS. LPS binding to cells appeared to be due to a nonspecific interaction between the lipid moiety of LPS and the lipid components of the cell membrane. Thus, the highly lipophilic, polysaccharide-deficient glycolipid from R595 bound at least 20 times better than did LPS. Furthermore, partial removal of cell surface proteins with trypsin or sialic acids with neuraminidase enhanced glycolipid binding, suggesting that binding is not through a protein- or sialic acid-containing receptor. The binding of glycolipid to lymphocytes was only partially specific since unlabeled glycolipid R595, lipid A, and LPS did not completely inhibit the uptake of 14C-labeled glycolipid R595. In addition, binding could be inhibited by a nonmitogenic phospholipid (phosphatidyl ethanolamine), which also is consistent with a nonspecific lipid-lipid interaction. Experiments were performed to determine the relationship of LPS binding to lymphocyte activation in the lymphocytes. The process of activation of lymphocytes by LPS was a slow one, since LPS was required to be present in culture for at least 24 h in order to obtain significant lymphocyte activation, suggesting that the amounts of LPS bound earlier are either quantitatively or qualitatively insufficient to irreversibly activate the cell.
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PMID:Binding of bacterial endotoxin to murine spleen lymphocytes. 29 51

Spleen cells from chickens inoculated 7 to 8 days previously with Marek's disease virus were cytotoxic for 51Cr-labeled cells of a Marek's disease lymphoblastoid cell line (MSB-1 line) in a 4-h in vitro cytotoxic assay. The cytotoxic activity of spleen cells was inhibited by pretreatment with antithymocyte serum and complement, but not with complement alone or in combination with anti-bursa cell serum or normal preimmune serum. The conclusion was that the effector cell in the above cytotoxic assay was a thymus-derived lymphocyte. Also, pretreatment of target cells with Vibrio cholerae neuraminidase enhanced in vitro cytotoxic activity of effector cells. Similar enzymatic treatment of effector cells had a negligible effect on cytotoxicity.
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PMID:Cell-mediated immunity to tumor antigen in Marek's disease: susceptibility of effector cells to antithymocyte serum and enhancement of cytotoxic activity by Vibrio cholerae neuraminidase. 30 27

BCG (Bacillus Calmette-Guerin) vaccine, Tice strain, caused a threefold increase in spleen weight of normal animals and a fourfold increase in spleen weight of sarcoma-bearing mice. In the latter group, the BCG vaccine caused infiltration of the sarcoma cells into the peritoneum and tumor metastasis in the spleen. Spleen lymphocytes from mice immunized with neuraminidase-treated sarcoma or from mice that had overcome an inoculum (100 cells) and a challenge (10(4) cells) of sarcoma P-1798 were cytotoxic against 51 Cr- or 14C-2-thymidine-labeled sarcoma cells. The serum of these mice enhanced the cytotoxic activity and inhibited the migration of the syngeneic lymphocytes. These serums also inhibited the migration of peritoneal macrophages from guinea pigs immunized with the sarcoma cells. BCG vaccine enhanced the development and growth of sarcoma P-1798; i.e., 50-100 viable sarcoma cells produced solid tumors in 8% of the untreated animals but in 100% of the BCG-treated animals. The serum of BCG-treated sarcoma-bearing animals inhibited the spleen lymphocyte-mediated cytotoxic action. The spleen lymphocytes from the BCG-treated sarcoma-bearing animals had no effect against 51Cr- or 14C-2-thymidine-labelled sarcoma cells. The data indicate that the serum from BCG-treated sarcoma-bearing animals blocks the spleen lymphocyte-mediated cytotoxic activities directed against proliferation and growth of the sarcoma.
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PMID:Mechanism of action of BCG vaccine on neoplastic proliferation and host immune responses. 126 78

Spleen cells from inbred Biozzi mice, immunized against the human breast cancer cell line T47D, were fused with murine myeloma SP2O cells to generate monoclonal antibodies. One of these, 1BE12, of IgM isotype, reacted with five of six human breast tumor cell lines, while no binding was detectable with normal lymphocytes, RBC, or fibroblasts. The antigen recognized by monoclonal antibody 1BE12 was localized on the surface of T47D and MCF7 cells and was detected in cell-free supernatants of cultures. The antigen was found also on the surface of milk secretory cells. Immunohistochemical staining of frozen and paraffin-embedded sections of human tissues showed apical polarized reactivity in normal breast glands, while in all breast cancers staining was either cytoplasmic or membranous and heterogeneously distributed. Immunostaining was also observed in some other normal epithelia, including salivary gland, gastroduodenal mucosa, exocrine pancreas, and cervix. The antigen was not detectable in secretory endometrium, whereas proliferative endometrium was strongly stained. Colon carcinoma, and cancers of the bladder and endometrium were strongly reactive. No staining was detected in melanoma, lymphoma, mesothelioma, non-small cell lung carcinoma, and thyroid, renal, and ovarian carcinomas. Lectin absorption of MCF7 membrane extracts reduced 1BE12 binding. A large reduction in 1BE12 reactivity was observed after digestion of T47D and MCF7 membrane extracts with proteases. Treatment with sodium periodate resulted in complete loss of antigenicity, while neuraminidase treatment did not affect 1BE12 binding. These findings suggest that the 1BE12 epitope is expressed on the carbohydrate moiety of a glycoprotein and does not contain sialic acid. Immunoblotting of the perchloric acid-soluble fraction of MCF7 membrane extracts after electrophoresis in 1% agarose detected the antigen as a high molecular weight species (Mr greater than 900,000). The antigen was purified by perchloric acid extraction of MCF7 membrane preparations followed by affinity chromatography on 1BE12 antibody coupled to Sepharose-4B and gel exclusion fast protein liquid chromatography. No reactivity of the purified material was found with monoclonal antibodies directed against human milk fat globule membrane-associated mucins HMFG1 and DF3.
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PMID:Characterization and distribution in human tissues of a glycoproteic antigen defined by monoclonal antibody 1BE12 raised against the human breast cancer cell line T47D. 222 61

Spleen cells from tumor-bearing mice showed decreased natural killer (NK) activity and decreased binding to target cells with progression of the tumor. Treatment of spleen cells from tumor-bearing mice with vibrio cholerae neuraminidase (VCN) increased the cytotoxicity to a level twice or more as high as that of untreated cells, but the same treatment of spleen cells from normal mice had no or little effect. On the other hand, neither in spleen cells from tumor-bearing mice nor in those from normal mice, the VCN treatment had no effect on their binding to M-HeLa cells. The suppression of NK activity by preincubation with serum from tumor-bearing mice or prostaglandin E2 was completely abolished by VCN treatment. The above results indicate that VCN treatment of lymphocytes might augment NK activity by an antagonistic effect against an immune suppressive factor.
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PMID:Augmentation of natural killer activity by neuraminidase treatment of lymphocytes from tumor-bearing mice. 242 36

Prior work has shown that purified, resident, and inflammatory peritoneal macrophages are weak stimulators of the allogeneic MLR. We have identified conditions whereby thioglycollate-elicited macrophages become stimulatory, but primarily for the CD8+ T cell subset. The conditions were to treat the macrophages with neuraminidase and to supplement the MLR with rIL-2. These treatments together led to proliferative and cytotoxic responses by isolated CD8+ but not CD4+ T cells. Likewise when MHC-congenic strains were evaluated, an MLR was observed across isolated class I but not class II MHC barriers. Pretreatment of the macrophages with IFN-gamma further enhanced expression of class I MHC products and stimulatory activity, but did not seem essential. While these treatments did not render macrophages stimulatory for an MLR in purified CD4+ cells, blastogenesis of CD4+ cells was observed when the MLR involved bulk T cells. Small allogeneic B lymphocytes behaved similarly to macrophages, in the pretreatment with neuraminidase and supplementation with rIL-2 rendered B cells stimulatory for allogeneic, enriched, CD8+, but not CD4+, T cells. Spleen adherent cells, which are mixtures of macrophages and dendritic cells, stimulated both CD4+ and CD8+ T cells, and neither neuraminidase nor exogenous IL-2 was required. We think that these data suggest that most macrophages and small B cells lack three important functions of dendritic cells: a T cell-binding function that can be remedied by neuraminidase treatment, a T cell growth factor-inducing function that can be bypassed with exogenous IL-2, and an IL-2 responsiveness function that is required by CD4+ lymphocytes.
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PMID:Neuraminidase-treated macrophages stimulate allogenic CD8+ T cells in the presence of exogenous interleukin 2. 326 11

Non-entrapped and liposome-entrapped Clostridium perfringens neuraminidase (0.5-0.6 unit) was injected into rats and its fate as well as its effect on plasma and erythrocyte N-acetylneuraminic acid was investigated. The following observations were made. (1) Although removal of both non-entrapped and liposome-entrapped neuraminidase from the circulation was completed within 5h after injection, their recovery in tissues was distinctly different; 7-10% of the injected non-entrapped enzyme was found in the liver and none in the liver lysosomal fraction or the spleen. In contrast, 20-26% of the liposome-entrapped enzyme was found in the liver of which 60-69% was in the lysosomal fraction. Spleen contained 3.6-5.0% of the enzyme. (2) The presence of the non-entrapped neuraminidase in blood led to the extensive desialylation of plasma and to a decrease in the concentration or total removal from the circulation of some of the plasma glycoproteins. (3) Injection of non-entrapped neuraminidase also led to the partial desialylation of erythrocytes the life span of which was diminished and their uptake by the liver and spleen augmented. (4) Entrapment of neuraminidase in liposomes before its injection prevented the enzyme from acting on its substrate in plasma or on the erythrocyte surface, and values obtained for plasma glycoproteins and erythrocyte survival were similar to those observed in control rats. (5) Entrapment in liposomes of therapeutic hydrolases intended for the degradation of substances stored within the tissue lysosomes of patients with storage diseases could prevent the potentially hazardous enzymic action of hydrolases in blood and at the same time direct the enzymes to the intracellular sites where they are needed.
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PMID:Comparative effect and fate of non-entrapped and liposome-entrapped neuraminidase injected into rats. 437 65

Spleen cells from mice immunized with the human lung cancer line SK-LC-3 were fused with mouse NS-1 myeloma cells. One of the hybrid clones produced a monoclonal IgM antibody (designated F-3), detected with antimouse Ig-MHA and hemagglutination assays. This antibody was completely absorbed by O red cells and completely inhibited by low concentrations of H(O) glycoproteins and hog mucin (A + H). Bombay (Oh) red cells completely failed to absorb F-3 activity even after treatment with neuraminidase. A1, A2, A1B, A2B, and B red cells and A- and B-glycoproteins were less effective in absorbing or inhibiting F-3 activity. Other glycoproteins (including those having Lea or blood group precursor structures) showed little or no inhibitory activity. Serum from nude mice carrying F-3 hybridoma agglutinated O and A2 red cells at a titer of 1:40,000 and 1:640, respectively. A1, A1B, A2B, and B red cells were agglutinated with titers of 1:80 or less. Monoclonal antibody F-3 is, therefore, highly specific for H(O) blood group determinants.
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PMID:Mouse monoclonal IgM antibody against human lung cancer line SK-LC-3 with specificity for H(O) blood group antigen. 620 22

Chromosome abnormalities were demonstrated in 50-100% of Giemsa-banded metaphases from nine cases of B-cell prolymphocytic leukemia (B-PLL). Mitoses were obtained with pokeweed mitogen following pretreatment of peripheral blood (PB) prolymphocytes with neuraminidase-galactose oxidase. Chromosome 14 was abnormal in eight of the nine cases: a marker 14q+, with breakpoint at band q32 in seven and trisomy 14 in one. In four cases the abnormal No. 14 was one of several primary abnormalities and in four others it was seen in secondary clones. The origin of the translocated material was unknown in three cases, in two it resulted from t(11;14), later becoming t(11;14;21) in one of them, t(1;14) in another, progressing later to t(1;14;17); in yet another patient, the 14q+ was the result of a complex rearrangement t(6;14;17). Abnormalities of chromosome 6 were seen in six cases: 6q- as the primary abnormality in three; trisomy 6 was part of secondary changes in one case. Structural abnormalities of chromosome 1 were seen in six cases: 1q- in four (in one as the only abnormality), 1q+ in one case, and 1p- in another, both in the main clone. Trisomy 12 was demonstrated in three cases but not as the primary change. Spleen cells in two patients showed a higher frequency of abnormalities than in the PB, supporting the concept of the spleen being the organ primarily involved in B-PLL. Evidence of karyotypic evolution was demonstrated in six patients, in some clearly associated with clinical progression of the disease. The type and frequency of the abnormalities observed in B-PLL resemble those seen in non-Hodgkin's lymphomas and suggest major differences from B-CLL, although a relationship with the latter can not be completely ruled out at present.
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PMID:Chromosome abnormalities in B-cell prolymphocytic leukemia: a study of nine cases. 660 59


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