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)

Spleen cells were modified with varying concentrations of trinitrobenzene sulfonic acid and then assayed for both their ability to stimulate syngeneic spleen cells into displaying a cytotoxic effect against TNP-modified target cells and for the extent of TNP derivatization of H-2 antigens. It was found that there was a direct correlation between the extent of derivatization of H-2 antigens and the ability of such derivatized cells to act as stimulator cells in the TNP-CML assay. Thus, these data lend support to the altered self or interaction antigen hypothesis as the explanation for the H-2 gene restriction of syngeneic CML. Target cells were also modified with TNBS at varying concentrations to determine the optimal concentration required to permit lysis in the CML assay. The results of these experiments indicate that similar concentration ranges of TNBS are required to create antigenic determinants on the target cells as well as immunogenic determinants on the stimulator cells that can be recognized by cytotoxic T cells.
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PMID:Relationship between trinitrophenyl and H-2 antigens on trinitrophenyl-modified spleen cells. II. Correlation between derivatization of H-2 antigens with trinitrophenyl and the ability of trinitrophenyl-modified cells to react functionally to the CML assay. 6 73

Spleen cells from H-2b,k,d C57Bl/10 congenic mice were sensitized in vitro to trinitrobenzenesulfonate (TNBS)-modified autologous spleen cells. Cold target competition studies at the lytic phase demonstrated three distinct patterns of cytotoxic responsiveness: (a) H-2b spleen cells generated approximately equivalent CTL responses against Kb and Db modified self products, (b) H-2d spleen cells generated preferential responses against Dd modified self products, and (c) H-2k spleen cells generated cytotoxic responses which could only be detected against Kk self products in association with TNP. F1 spleen cells were sensitized against autologous TNBS-treated cells. The results showed that, although H-2b parental cells generated approximately equivalent Kb-TNP- and Db-TNP-specific CTL, the presence of the H-2b haplotype did not result in the generation of (a) Dk-TNP CTL response by (H-2b x H-2k) spleen cells, nor (b) a Db CTL response by (H-2b x H-2a) F1 spleen cells. Additionally, (H-2d x H-2k) F1 cells failed to generate detectable Dd-TNP-specific CTL, although H-2d parental cells generated D-regional-specific CTL. The findings demonstrated that these F1 response patterns paralleled those of the H-2k and H-2a parents, i.e. weak or no D-region TNP-specific CTL were induced. Because (H-2d x H-2a) F1 responders stimulated with H-2d TNBS-treated cells did generate good Dd TNP responses, the results illustrated that the presence of responder genes was not sufficient to result in a D-region TNP CML. It is suggested that the absence of Kk alleles on the stimulating population is necessary for the generation of D-region TNP CTL in these F1's. Mechanisms which could account for these response patterns in parental F1 mice are discussed including immunodominance, suppression, T-cell response , and Ir-gene defects.
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PMID:Regulation of T-cell-mediated lympholysis by the murine major histocompatibility complex. I. Preferential in vitro responses to trinitrophenyl-modified self K- and D-coded gene products in parental and F1 hybrid mouse strains. 10 68

Spleen and thymus cell populations from normal or allograft tolerant mice have been cultured for 5 days with specific alloantigens and examined for their reactivity in three assay systems. No consistent correlation was observed between the production of cytotoxic T cells (CTL) in these cultures and the ability of such cultured cells to inhibit specifically a CML response from fresh normal spleen cells directed to the priming alloantigens. Furthermore, suppressor cells measured in this latter assay were apparently distinct from those able to inhibit the production of cytotoxic lymphocyte precursors (CTLp) from bone marrow stem cells in lethally irradiated bone marrow protected mice. Velocity sedimentation experiments confirmed that both the precursor and effector cells for the two suppressor systems were physically separable, and were distinct from CTLp or CTL, respectively. Precursor cells for the two suppressor systems investigated belong to the short-lived cortical thymus cell population.
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PMID:Suppression of cytotoxic response to histoincompatible cells. I. Evidence for two types of T lymphocyte-derived suppressors acting at different stages in the induction of a cytotoxic response. 31 22

We analyzed the role of CD4+ and CD8+ T cells in H-2-disparate skin allograft rejection in the mutant mouse strain C.B-17/Icr scid with severe combined immunodeficiency. On the day of skin allografting, scid mice were adoptively transferred with negatively selected CD4+ or CD8+ splenocytes from normal unsensitized C.B-17/Icr mice. These populations were obtained using a double-mAb--plus--complement elimination protocol using anti-CD4 or anti-CD8 mAb that resulted in no detectable CD4+ or CD8+ cells by FACS and negligible numbers of cytolytic T lymphocytes by limiting dilution analysis in anti-CD8 treated populations. Spleen cells were removed from grafted mice at the time of rejection and were tested in vitro for antidonor reactivity in several assays: mixed lymphocyte culture, cell-mediated lympholysis, and LDA for CTL and for IL-2-producing HTL. The presence of Thy 1.2+, CD4+, or CD8+ cells was determined by FACS. All control C.B-17 mice and scid mice adoptively transferred with nondepleted CD4+, and CD8+ cells rejected skin allografts with similar mean survival times (15.6 +/- 1.5, 18.8 +/- 3.4, 18.0 +/- 5.4, respectively), whereas control scid mice retain skin allografts indefinitely (all greater than 100 days). C.B-17 syngeneic grafts survived indefinitely in all groups. At the time of rejection, splenocytes from scid mice receiving CD4+ cells had negligible donor-specific cytotoxicity in CML and negligible numbers of CTL by LDA, but demonstrated a good proliferative response in MLC and IL-2-producing cells by LDA (frequency = 1/1764). There were no detectable CD8+ cells present by FACS analysis. Conversely, splenocytes from scid mice adoptively transferred with CD8+ cells had strong donor-specific cytotoxicity in CML (58.8% +/- 16.1%) and CTL by LDA (frequency = 1/3448), but no significant proliferation was detected in MLC. There were no detectable CD4+ cells by FACS, but there were small numbers of IL-2-producing cells by LDA (frequency = 1/10,204). These data demonstrate that CD4+ cells adoptively transferred into scid mice are capable of mediating skin allograft rejection in the absence of any detectable CD8+ cells or significant functional cytolytic activity. The adoptive transfer of CD8+ cells also results in skin allograft rejection in the absence of detectable CD4+ cells. The detection of small numbers of IL-2 secreting cells in these mice may indicate that CD(8+)-mediated allograft rejection in this model is dependent on IL-2-secreting CD8+ cells.
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PMID:Mediation of skin allograft rejection in scid mice by CD4+ and CD8+ T cells. 135 12

Spleen function was evaluated by measurement of the clearance of autologous heat-damaged 99mTc-labelled erythrocytes from the circulation and into the spleen and the enumeration of pitted erythrocytes by interference contrast microscopy, and the spleen area was determined by scintillation scanning. All measurements were performed on 12 patients with chronic myelogenous leukemia and compared with 10 controls with apparently normal spleens, 6 splenectomized subjects and 9 patients with a reactive splenomegaly. Patients with CML had spleen function test results similar to normal controls in spite of having enlarged spleens whose projection area did not differ from that of the patients with reactive splenomegaly. Thus, patients with CML have a decreased spleen function per unit volume and signs of splenic hypofunction in the peripheral blood. The reduction of spleen function per unit volume in CML is the result of a severe decrease of the splenic blood perfusion which could result from the combined effects of the myeloid metaplasia and the increased whole-blood viscosity due to high white-cell counts.
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PMID:Splenic function in chronic myelogenous leukemia. 348 Feb 38

After orthotopic transplantation of rat livers from Lewis (LEW) donors into Wistar Furth (WF) recipients, a rejection response occurs 2 weeks after transplantation, followed by indefinite survival of the transplant. Spleen cells from WF rats bearing long-term LEW liver grafts responded in MLR and CML assays like spleen cells from normal WF rats after in vitro stimulation with mitomycin C-treated LEW spleen cells, but did not generate CTL after stimulation with paraformaldehyde-treated LEW spleen cells. Transient damage to the long-term grafted livers was induced by inoculation of recipients with homogenized normal LEW liver. CD8+ CTL were detected in the spleen at the time of this liver damage. These findings indicate that CTL precursors are present in WF rats bearing LEW liver transplants. These CTL precursors are capable of differentiating into effector CTL in vitro and in vivo in response to donor antigen. However, once generated, effector CTL in WF rats are eliminated or become unresponsive to the transplanted LEW liver. Homogenized LEW liver from grafted donors did not induce transient liver damage when inoculated into recipient WF rats bearing LEW liver transplants. The demonstration of large amounts of antibody bound to either parenchymal or nonparenchymal cells in the donor graft suggests that reduction (or loss) of antigenicity could also be responsible for the inability of LEW liver to elicit an immune response in WF-recipient rats. Thus, elimination or inactivation of effector CTL and altered antigenicity could both be responsible for maintaining tolerance after allogeneic liver transplantation.
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PMID:Long-term survival of orthotopic Lewis liver grafts in Wistar Furth rats. Elimination or inactivation of effector CTL and altered antigenicity as possible reasons for tolerance. 810 77