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Query: UMLS:C0018133 (graft-versus-host disease)
 18,032 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Current studies suggest that the depletion of T-lymphocytes from donor marrow is an effective method for preventing acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation in man. To deplete the T-lymphocytes from bone marrow cells we use either monoclonal anti-T-cell antibodies and complement or T101 ricin A-chain immunotoxin. Residual T-lymphocytes are analyzed by their capacity to form clonal T-cell colonies in the presence of phytohemagglutinin (PHA), accessory cells, and recombinant interleukin 2. The method is compared to immediate indirect immunofluorescence (iF) and thymidine incorporation by marrow cells stimulated by PHA. IF is not suitable for evaluating the depletion by immunotoxin, and the interpretation of thymidine incorporation is generally questionable. The results of the colony formation show that the sensitivity of the colony assay is close to that of iF when T cells are depleted by complement lysis, and the sensitivity of the colony assay is not dependent upon the depletion procedure. Therefore, the T-cell colony assay is a simple functional control for the quality of bone marrow T-cell depletion, especially for T-cell depletion by immunotoxin.
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PMID:Clonal T-cell colony formation in agar culture: an attractive assay to test the T-cell depletion from bone marrow. 353 43

We studied the presence of peripheral-blood- and bone-marrow-derived T-lymphocyte colony formation (CFU-TL) in 28 bone marrow transplant recipients from 1 month to six years after transplantation. Peripheral blood leukocyte and lymphocyte counts were generally normal, and all had morphologic evidence of engraftment without leukemia at the time of study. Both peripheral-blood- and bone-marrow-derived CFU-TL were markedly reduced after transplantation as compared to normal controls, which included bone marrow donors (14.2 +/- 5/4 X 10(4) vs 313 +/- 100/4 X 10(4) [p less than 0.001] and 26 +/- 4/2 X 10(5) vs 1004 +/- 60/2 X 10(5) [p less than 0.001]). Among the patients, four had no detectable bone-marrow-derived CFU-TL when tested less than six months after transplantation. Peripheral blood CFU-TL, while present in all patients, was markedly decreased for more than 12 months after transplantation. After two years, the number of CFU-TL returned to normal in several patients. The abnormalities in CFU-TL were unrelated to diagnosis, age, sex, graft-versus-host disease (GVHD), pretransplant conditioning, or posttransplant immunosuppressive treatment. Patients receiving autologous bone marrow transplants also had decreased CFU-TL. Cocultures of normal peripheral-blood- or bone-marrow-derived mononuclear cells with recipients' mononuclear cells or sera did not inhibit normal CFU-TL growth. Furthermore, the addition of mononuclear cells or sera from normal individuals, or of exogenous interleukin 1 or interleukin 2, did not correct the deficiency of CFU-TL growth by recipient cells. Depletion of T-lymphocytes from bone marrow or peripheral blood in transplant recipients by physical techniques or with a monoclonal antibody (CT-2) and complement had no effect on CFU-TL recovery. Similarly, addition of recipients' T cells to normal peripheral blood or bone marrow mononuclear cells did not suppress CFU-TL. These data indicate that most transplant recipients have a marked reduction in CFU-TL which persists for up to two years after transplantation. This reduction in the growth of T-cell colonies appears to be due to deficient numbers of these cells or an intrinsic defect in their responsiveness to T-cell lymphokines, rather than a result of growth suppression by inhibitory cells or serum factors. This observed defect in CFU-TL may have implications for therapeutic attempts to facilitate immune reconstitution after bone marrow transplantation.
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PMID:Abnormal T-lymphocyte colonies (CFU-TL) following bone marrow transplantation. 353 45

Highly purified human recombinant interleukin 2 (IL-2) markedly accelerated lethal GVHD in the H-2-identical B10.BR----CBA combination, but had no effect when the donor cells were depleted of mature (Thy-1.2-positive) T lymphocytes, indicating a strong immunopotentiating effect of IL-2 on mature T cells causing GVHD. In the same donor-host combination, IL-2 did not influence the recovery from the post-transplantation bone marrow aplasia. The results suggest that IL-2 could be considered for adjuvant hormonal therapy to enhance immune recovery in recipients of T-cell-depleted allogeneic marrow.
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PMID:T-cell depletion of allogeneic bone marrow prevents acceleration of graft-versus-host disease induced by exogenous interleukin 2. 354 38

Peripheral blood mononuclear leukocytes (cells of marrow donor origin) from 89 patients were collected at various times after allogeneic marrow transplantation, stimulated in vitro by phytohemagglutinin, and assayed for the production of interleukin 2 (IL-2). This was done by testing culture supernatants for their ability to induce proliferation of human lymphoblasts and/or IL-2-dependent cultured murine cytotoxic cells. Supernatants from cultures of patient cells were compared with those of marrow donor cells. Supernatants produced by cells from most short-term marrow recipients (30-101 days postgrafting), regardless of the presence or absence of acute graft-versus-host disease (GVHD), and those from most long-term patients with chronic GVHD (103-1932 days postgrafting) had significantly lower-than-normal IL-2 activity, whereas cells from most long-term marrow recipients without GVHD (353-1934 days postgrafting) had essentially normal IL-2 activity. Additionally, we tested the ability of monocytes from 35 marrow recipients to produce interleukin 1 (IL-1) in response to lipopolysaccharide as compared with monocytes from marrow donors or normal unrelated individuals. IL-1 activity in culture supernatants of patient cells, regardless of the time of testing after marrow grafting and the status of GVHD, was found not to differ from that in supernatants of normal cells. These findings suggest that impaired T cell functions seen in some (but not all) marrow recipients are probably not due to IL-1 but to IL-2 deficiency or to the mechanism that causes IL-2 deficiency.
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PMID:Cellular interactions in marrow-grafted patients. III. Normal interleukin 1 and defective interleukin 2 production in short-term patients and in those with chronic graft-versus-host disease. 388 Sep 62

We have recently demonstrated, in a fully MHC-mis-matched murine bone marrow transplantation (BMT) model, that administration of a short course of high-dose interleukin 2 (IL-2) markedly delays the onset of graft-versus-host disease (GVHD) without compromising alloengraftment or the graft-versus-leukemia (GVL) effect of allogeneic T cells. Early timing of IL-2 administration and high dose were shown to be critical to achieve this protective effect. Although a 2.5 day course of IL-2, begun on the day of BMT, was found to confer marked protection without observable toxicity, shorter courses and a higher dose of IL-2 than 5 x 10(4) Cetus units per treatment have not been previously evaluated in this model. We now demonstrate that administration of a three-treatment course of IL-2 over a 25 h period beginning 15 h following BMT is sufficient to provide maximal GVHD protection, that increasing the IL-2 dose beyond 5 x 10(4) units per treatment does not further improve the level of GVHD protection, and that further division of IL-2 treatments to achieve more constant tissue levels does not result in improved GVHD protection. We also demonstrate that IL-2 is still protective when administered in combination with cyclosporine. These results suggest that IL-2 administered in a sufficient short course to avoid toxicity might have the potential to achieve effective GVHD prophylaxis in humans, even if given in combination with cyclosporine.
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PMID:IL-2-induced GVHD protection is not inhibited by cyclosporine and is maximal when IL-2 is given over a 25 h period beginning on the day following bone marrow transplantation. 759 64

Six patients treated for relapsed chronic myeloid leukaemia after allogeneic bone marrow transplantation with donor buffy coat transfusions were investigated. In the 5 patients who achieved molecular remission high frequencies of host-reactive interleukin 2-secreting T helper cell precursors (Th-p) were detectable by limiting dilution analysis. In four of the patients the presence of Th-p was associated with a clinical syndrome similar to transfusion GVHD suggesting a T cell response to minor histocompatibility antigens (minor H) expressed by both malignant haemopoiesis and host tissues. In the fifth responding patient no GVHD or bone marrow hypoplasia was observed. The nature of the antigens recognised by these donor Th-p remains unknown. No host-reactive Th-p were detectable in the non-responder and host-reactive cytotoxic T cell precursors (CTL-p) were not consistently detectable in the responding patients.
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PMID:Successful therapy with donor buffy coat transfusions in patients with relapsed chronic myeloid leukemia after bone marrow transplantation is associated with high frequencies of host-reactive interleukin 2-secreting T helper cells. 767 Apr

We investigated the role of interleukin 2 (IL-2)-secreting T helper cell precursors (Th-p) in primary and secondary chronic graft-versus-host disease (GVHD). Twelve patients with chronic GVHD (8 primary and 4 secondary chronic GVHD) and 8 patients without chronic GVHD were investigated using a sensitive limiting dilution assay. High frequencies of host-reactive interleukin 2-secreting T helper cell precursors were detectable in all patients with chronic GVHD irrespective of the mode of onset. Host-reactive IL-2-secreting T helper cell precursors disappeared in patients whose GVHD resolved. Host-reactive IL-2-secreting T helper cell precursors were never found in the control patients without chronic GVHD. Host-reactive cytotoxic T cell precursors (CTL-p) were not consistently detectable in patients with chronic GVHD and were occasionally found in patients without GVHD. No autoreactive IL-2-secreting T helper cell precursors or cytotoxic T cell precursors were detectable in either group. The absence of autoreactive IL-2-secreting T helper cell precursors in patients was confirmed by clonal specificity analysis in 4 patients. These data suggest a role for host-reactive IL-2-secreting T helper cell precursors in the initiation and maintenance of chronic GVHD as previously shown for acute GVHD.
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PMID:Presence of host-specific interleukin 2-secreting T helper cell precursors correlates closely with active primary and secondary chronic graft-versus-host disease. 767 Apr 2

CD4+ and CD8+ TCR alpha beta+ T-cell clones were derived from 4 leukaemia patients early (4-6 weeks) after allogeneic bone marrow transplantation. Leukemia inhibitory factor (LIF) secretion in response to the activation signal accessory cells (AC) + phytohaemagglutinin (PHA) was investigated for each individual clone. Only a minority of CD4+ TCR alpha beta+ T-cell clones secreted LIF in response to AC + PHA, whereas most T-cell clones were capable of LIF secretion when exogenous interleukin 2 was added together with AC + PHA. LIF secretion could also be demonstrated for CD8+ TCR alpha beta+ posttransplant T-cell clones. Thus, posttransplant CD4+ and CD8+ TCR alpha beta+ clonogenic T-cells are capable of LIF secretion, and LIF secretion may be a T-cell effector mechanism in graft versus host disease, graft versus leukaemia effects or posttransplant haematopoietic reconstitution.
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PMID:Secretion of leukaemia inhibitory factor after allogeneic bone marrow transplantation: a study of CD4+ and CD8+ TCR alpha beta+ T-cell clones derived from four leukaemia patients. 769 92

In this study we describe immunotoxins prepared with different CD2 monoclonal antibodies (mAbs) and a ribosome-inactivating protein, saporin. The CD2 immunotoxins were tested on different models. Anti-CD2-saporin conjugates inhibited protein synthesis by a neoplastic CD2+ cell line (SKW-3) and by an interleukin 2 dependent polyclonal CD2+ lymphoid cell culture (T lymphoblasts), with IC50s ranging from 10(-13) M to 10(-11) M (as saporin). Similar results were obtained with proliferation inhibition tests (3H-thymidine incorporation) on phytohaemagglutinin (PHA) driven lymphoid cultures and on mixed lymphocyte culture activated lymphocytes. Moreover a CD2-ricin A chain conjugate was less effective than an analogous immunotoxin containing the same CD2 mAb and saporin in inhibiting lymphocyte proliferation induced by PHA (IC50 approximately 10(-9) M as ricin A chain versus 10(-12) M as saporin). The conjugates were not toxic on bone marrow stem cells. These results suggest that CD2-saporin immunotoxins could represent an effective tool for CD2+ lymphomas or leukaemias, and for T-dependent immune disorders, such as transplanted organ rejection and graft-versus-host disease.
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PMID:Immunotoxins containing saporin linked to different CD2 monoclonal antibodies: in vitro evaluation. 791 1

The expression of interleukin 2 (IL-2), induction of its multisubunit receptor and subsequent interplay of this ligand with its receptor are pivotal events in T-cell activation. Our present understanding of the normal IL-2/IL-2 receptor system, and of disorders in this network in disease, opens the possibility for more specific immune intervention. Thomas Waldmann discusses how the clinical application of IL-2, agents that inhibit IL-2 synthesis and action, and anti-IL-2 receptor-directed therapy provide a novel perspective for prevention of allograft rejection and for treatment of graft-versus-host disease, select autoimmune disorders and certain neoplastic diseases.
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PMID:The IL-2/IL-2 receptor system: a target for rational immune intervention. 821 11


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