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

Spleen or bone marrow cells from (C57BL/6 X DBA/2)F1 hybrid mice ranging in age from 1 to 32 days were transplanted into syngeneic irradiated adult recipients. By enumeration of macroscopic hemopoietic spleen colonies 8 days after transplantation, the colony-forming unit(CFU) content of the spleen and bone marrow of the young donor mice was determined. The CFU concentration in the bone marrow, initially at a level of 15.1--17.0 CFU/105 nucleated cells, increased during the third week of life and reached a value comparable to that of the adult during week 4. In contrast, the CFU concentration of the spleen decreased during the first 2 weeks and reached a plateau at a level of 4.45--6.66 CFU/105 nucleated cells during the third and fourth weeks of age. This was still significantly higher than that of the adult hybrid. The rise in prominence of the bone marrow as a hemopoietic organ during this period appeared to be due to an increase in total cellularity coupled with an increase in CFU concentration in this hybrid. While the cellularity of the spleen also increased during this time, the CFU concentration decreased, resulting in little change in the total CFU content of this organ.
 ...
PMID:Colony-forming units in the spleen and bone marrow of young (C57BL/6xDBA/2)F1 hybrid mice. 68 54

Spleen cells from mice infected with Friend leukemia virus (FLV) inoculated by the intravenous route give rise to macroscopically visible colonies in the spleens of normal F1 histocompatible hybrid hosts. A study of H-2 antigens as generic markers for identification of strains of origin of cells constituting the spleen colonies was undertaken. The standard cytotoxic test was demonstrated to be suitable for characterizing the H-2 antigens present on the surface of spleen cells from normal of FLV-leukemic parents of F1 hybrid mice. Individual colonies dissected out of the spleen of (C3HxC57B6/6) F1 recipients (H-2k/H-2b), 10 days after the intravenous graft of FLV-infected spleen cells of C3H origin (H-2k), were all sensitive to anti-C57BL/6 antibodies. In the same way, colonies obtained from the spleens of (DBA/2xC57BL/10) F1 recipients (H-2d/H-2b) grafted with DBA/2 leukemic spleen cells (H-2d) were all sensitive to both anti-H-2b and anti-H-2d antibodies. These results directly prove that the main cell population constituing a spleen colony arises from the recipient. The authors conclude that the spleen colonies do not result from the neoplastic proliferation of injected donor cells but rather from the multiplication of host cells transformed by Friend virus produced by the grafted cells.
 ...
PMID:Oncogenicity of Friend-virus-infected cells: determination of origin of spleen colonies by the H-2 antigens as genetic markers. 70 Sep

Spleen cells from CBA/N mice with an X-linked B cell defect were examined for their ability to form antibody in vitro after stimulation with the T-independent antigen TNP-LPS. In contradistinction to their failure to respond to some conventional T-independent antigens such as type III pneumococcal polysaccharide or DNP-AECM-Ficoll, spleen cells from (CBA/N X DBA/2)F1 male mice were able to make a specific anti-TNP PFC response after culture with TNP-LPS. Their response differed from that of phenotypically normal (CBA/N X DBA/2)F1 female littermate spleen cells in that more TNP-LPS was required to elicit the peak anti-TNP response and the anti-TNP antibody secreted by F1 male cells was of lower avidity than that of F1 female cells. The polyclonal antibody response to unsubstituted LPS did not differ substantially between normal and defective B cells. Tnymus-derived cells were not required for the TNP-LPS response by either F1 male or female cells. We conclude that CBA/NB cells can respond to certain T-independent antigens that are able either to induce a very strong activating signal upon ligand-surface receptor interaction and/or to stimulate immature B cells (with a characteristic high surfact immunoglobulin profile) which fail to respond to antigens like DNP-AECM-Ficoll.
 ...
PMID:In vitro responses of CBA/N mice: spleen cells of mice with an X-linked defect that precludes immune responses to several thymus-independent antigens can respond to TNP-lipopolysaccharide. 78 72

The relationship between T cells involved in cell-mediated immunity and antibody response of C57Bl/6J mice towards DBA/2 mastocytoma cells was investigated. Spleen cells primed with viable mastocytoma cells demonstrated marked cell-mediated cytotoxicity (CMC) in vitro, but antibody response of these cells to a hapten (TNP) conjugated to the allogeneic tumour cells in vitro was suppressed as compared with that of normal spleen cells. In contrast, spleen cells primed with frozen-thawed mastocytoma cells showed no CMC, but antibody response to the hapten in vitro of these cells was enhanced. C57Bl/6J mice primed with frozen-thawed mastocytoma cells produced more cytotoxic antibody than non-primed mice when immunized with viable mastocytoma cells. These results indicate that T cells involved in cell-mediated immunity and those involved in the antibody response to allogeneic mastocytoma cells are distinct.?222
 ...
PMID:The relation between the T cells responsible for cell-mediated cytotoxic killing of mastocytoma cells and the helper-cell effect. 80 16

Spleen cells from normal DBA/2 mice pretreated with a soluble factor from mastocytoma cells or from ascitic fluid of mastocytoma-bearing mice were markedly impaired in terms of antibody formation to SRBC in vitro. Such immunosuppression by mastocytoma homogenates or ascitic fluid was reversed when syngeneic T cells activated to SRBC were added to the cultures, but not when peritoneal exudate cells or anti-theta-treated normal splenocytes were used. Activated T cells, as well as normal B lymphocytes prepared from spleens of lethally irradiated mice reconstituted with bone marrow cells, were less sensitive to the immunosuppressive factor than non-activated T cells. The ability of educated T cells to restore immunocompetence of suppressed spleen cells in vitro suggests that the target of the immunosuppressive factor from mastocytoma cells may be non-activated T cells, especially those involved in T cell helper function.
 ...
PMID:Restoration of in vitro immune responsiveness of mastocytoma-suppressed splenocytes by activated T cells. 80 35

Spleen cells from normal (C57BL/6 X DBA/2)F1 mice were sensitized in vitro for 5 days with irradiated C57BL/6 or DBA/2 parental stimulating cells. Effector cells were generated which specifically lysed 51Cr-labeled targets (leukemia or mitogen-stimulated lymphoid cells) H-2-matched with the parental genotype used for sensitization. The response of F1 spleen cells to the C57BL/6 parent was stronger and more reproducible than that to the DBA/2 parent. The kinetics of generation of effector cells were similar for the F1 anti-parent and an F1 anti-allogeneic response. However, the magnitude of the F1 anti-C57BL/6 cytotoxic response was considerably lower than the F1 response to allogeneic cells. The ratio of responder to stimulator cells in the cultures was more critical for the former than for the latter response. Several lots of fetal bovine serum were found to be adequate for supplementing the medium in the induction of J1 hybrid anti-parent and anti-allogeneic cytotoxic effector cells. Based on these and other studies, it would appear that the F1 hybrid anti-parent cytotoxic response provides an in vitro model of murine hemopoietic graft rejection in vivo. This response may be elicited by a mechanism distinct from T cell-mediated cytotoxicity and involve different subpopulations of spleen cells.
 ...
PMID:In vitro induction of F1 hybrid anti-parent cell-mediated cytotoxicity. 95 51

Friend virus induces a leukemia characterized by the proliferation of neoplastic hematopoietic cells believed to be erythroid precursors. In vitro studies were conducted with spleen cells from mice with terminal Firend leukemia in order to determine their capacity for leukocytic differentiation. Spleen cells were obtained from leukemic DBA/2 mice 1 to 2 days before anticipated death and cultured in the presence or absence of colony-stimulating activity (CSA). Growth in liquid culture in dissusion chambers was dependent on CSA and resulted in the generation of normally differentiated granulocytes and macrophages. Colony formation in agar was also dependent on CSA, and the cloning efficiency of leukemic spleen cells was found to be approximately 10 times normal. The colonies formed were composed of leukocytes, which appeared morphologically normal. Total in vitro colony-forming units per leukemic spleen exceeded normal by more than 300-fold, but cells elaborating CSA were decreased. Although it is uncertain whether the stem cells stimulated by CSA are "normal" or leukemic," it is clear that Friend leukemia has profound effects on the proliferation and differentiation of nonerythroid stem cells.
 ...
PMID:Granulocytic stem cells in Friend leukemia. 108 68

Vaccinia virus specific cytotoxicity against infected target cells was observed in vitro. Spleen lymphocytes from normal and immunized mice of the inbred strains C3H and DBA/2 were incubated with vaccinia virus-infected and non-infected 51 Cr-labeled mastocytoma P-815-X2 cells and L-929 fibroblasts, which were used as targets. Cytotoxic lymphocytes could be isolated from the mice as early as 2 days after infection with vaccinia virus. The highest cytotoxic effect was obtained with lymphocytes taken 6 days after infection. The degree of lysis was correlated with the ratio of immune lymphocytes to target cells. Specific blocking of target cell lysis resulted after addition of anti-vaccinia antibody from different sources. The effector cells could be characterized as T cells by elimination of macrophages and B cells. Target cell killing was only possible in a syngeneic system; allogeneic infected target cells were not lysed significantly.
 ...
PMID:Target cell-dependent T cell-mediated lysis of vaccinia virus-infected cells. 108 29

The immunogenicity of lymphoma L1210 and three L1210 sublines, resistant to methylglyoxal bis(guanylhydrazone), 4,4'-diacetyldiphenylurea bis(guanylhydrazone), or guanazole (L1210/GZL), respectively, was evaluated. Syngeneic DBA/2J mice were given a single i.p. injection of serially diluted suspension of irradiated cells from L1210 or L1210 sublines. Five days later spleen cells from the immunized mice were tested for the presence of plaque-forming cells using the immunizing lymphoma cell lines as target. Sera collected from the animals were examined for cytolytic antibody activity by lysis in gel using the same target cells. For comparison, the H-2 immunogenicity of L1210 and its sublines was investigated in H-2-incompatible allogeneic mice. The following results were obtained. (a) All the sublines showed increased immunogenicity and susceptibility to lysis as compared to L1210 cells. The number of plaque-forming cells/spleen ranged from 100 for L1210 to 4450 for L1210/GZL, the most immunogenic subline, and the antibody titer ranged from 1/8 for L1210 to 1/128 for L1210/GZL. (b) All the sublines carried common tumor-associated antigens that apparently made primary contributions to the increased immunogenicity. (c) The common tumor-associated antigens were also expressed on L1210 cells, although in a lesser defree, as evidenced by the definite, albeit low, capacity of L1210 cells to absorb DBA/2J anti-L1210/GZL antibodies. (d) Spleen and thymus cells of DBA/2J mice as well as unrelated murine ascites tumor cells did not cause significant absorption of these antibodies. (e) Only a partial inverse relationship could be demonstrated between tumor-associated antigens but the lowest for H-2. The above results would seem compatible with the hypothesis that the increased immunogenicity of drug-resistant L1210 sublines is attributable to the selection of preexisting highly immunogenic cells during immunosuppression by treatments selecting for drug resistance.
 ...
PMID:Selection for high immunogenicity in drug-resistant sublines of murine lymphomas demonstrated by plaque assay. 109 Mar 66

Spleen cells from a C57BL/6 mouse allografted with DBA/2 skin may release a macrophage arming factor when stimulated with phytohemagglutinin. This in vitro nonspecific release is observed only when the recipient cells are collected during a limited period preceding or coinciding with graft rejection. The phenomenon disappears if the skin allograft has been removed before cell collection. It appears if an i.v. injection of donor cells is given to the recipient after graft removal, on the day preceding cell collection. These data suggest that this in vitro apparently nonspecific macrophage arming factor release by phytohemagglutinin-stimulated recipient cells may in fact disclose a previous specific in vivo immune cell triggering by graft antigens.
 ...
PMID:Macrophage arming factor release by allografted mouse lymphocytes stimulated by phytohermgglutinin. 115 86


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>