Gene/Protein Disease Symptom Drug Enzyme Compound
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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)

We have established a murine model to compare the antileukemic effect of PBPC grafts obtained after treatment with SCF + G-CSF and G-CSF alone. C57/BL6, DBA and Balb/c mice were splenectomized and injected with optimal doses of rhG-CSF (250 microg/kg/day s.c.) or rrSCF (100 microg/kg/day s.c.) or with a combination thereof. On day 5, we determined the hematopoietic potential (number of CD34+ cells, CFUs, total CFC, CFU-gm), the proportion of lymphoid (T, NK and B cells) and myeloid components and graft-versus-leukemia activity after allogeneic and syngeneic PBPCT and BMT in Balb/c mice bearing a B-lymphoblastic leukemia cell line (A20). The absolute number of progenitor cells increased two-fold after administering a combination of G-CSF and SCF as compared to G-CSF alone (1500 vs 940 CD34+ cells/microl; 190 vs 70 total CFC/microl; 150 vs 50 CFU-gm/microl and 6600 vs 3000 CFUs/ml). Although no differences could be detected in the cellular composition, especially in the number of T cells, PBPC grafts mobilized by the combination of G-CSF + SCF demonstrated significantly higher antileukemic activity compared to G-CSF alone (94% vs 71% freedom from leukemia, P < 0.05). Because the incidence of lethal GVHD was similar in both groups, improved GVL activity resulted in superior overall survival. Our data suggest that the higher number of progenitor cells can be harvested after G-CSF + SCF and that grafts mobilized by G-CSF + SCF exert significantly enhanced antileukemic activity compared to those harvested after treatment with G-CSF alone.
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PMID:Superior antileukemic activity of murine peripheral blood progenitor cell (PBPC) grafts mobilized by G-CSF and stem cell factor (SCF) as compared to G-CSF alone. 971 86

Gammadelta T cells have been implicated in the pathogenesis of acute graft-versus-host disease (GVHD). We therefore performed experiments to determine whether mortality from GVHD is reduced in C57BL/6 x DBA/2 F1-hybrid (BDF1-hybrid) mice when parental strain, T-cell receptor-delta (TCRdelta) knockout (KO) donors are used. We compared mortality, weight loss, interferon-gamma (IFN-gamma) production and cytotoxic activity in recipients of either wild-type or TCRdelta KO grafts. In both groups there was significant weight loss and an identical level of mortality. Elevated IFN-gamma levels were present in both groups, but recipients of TCRdelta KO grafts produced twice as much as recipients of wild-type grafts. Elevated natural killer (NK) and NK-like activity was also seen in both. These results demonstrate that TCRdelta KO grafts can induce GVHD as severe as that seen in recipients of wild-type grafts, a finding that is at odds with studies demonstrating reduced mortality when gammadelta T cells are purged from donor mice. We suggest that the inconsistency may lie in the higher levels of IFN-gamma seen with TCRdelta KO grafts and that the protection afforded by the absence of gammadelta T cells in the graft is overwhelmed by the higher levels of IFN-gamma.
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PMID:Acute, lethal graft-versus-host disease in an F1-hybrid model using grafts from parental-strain, T-cell receptor-delta gene knockout donors. 974 12

Because CD28-mediated T-cell costimulation has a pivotal role in the initiation and maintenance of T-cell responses, we tested the hypothesis that CD28 is critical for the development of graft-versus-host disease (GVHD). We compared the in vivo effects of CD28(-/-) T cells transplanted from B6 donor with the CD28 gene deleted by homologous recombination with those of CD28(+/+) T cells transplanted from wild-type C57BL/6 (B6) donor. Fifty million CD28(-/-) or CD28(+/+) splenocytes from B6 mice were transplanted into unirradiated (B6 x DBA/2)F1 (BDF1) recipients. Unlike CD28(+/+), CD28(-/-) T cells from B6 mice had lower levels of proliferation and interleukin-2 production, had a limited ability to generate cytotoxic T lymphocytes against the recipient, and did not induce immune deficiency, despite survival in the recipient for at least 28 days. The ability to prevent rejection was reduced by the absence of CD28, because as many as 1.0 x 10(7) CD28(-/-) CD8(+) cells were needed to prevent rejection of major histocompatibility complex (MHC) class-I incompatible marrow in sublethally irradiated (550 cGy) bm1 recipients, whereas 8.0 x 10(5) CD28(+/+) CD8(+) T cells were sufficient to produce a similar effect, indicating that CD28 on donor CD8(+) cells helps to eliminate host immunity. Two million CD4(+) CD28(-/-) or CD28(+/+) T cells were transplanted into sublethally irradiated (750 cGy), MHC class-II incompatible (B6 x bm12)F1 recipients. With CD28(-/-) cells, 44% of the recipients died at a median of 20 days compared with 94% at a median of 15 days with CD28(+/+) cells (P < .001). Two million CD8(+) CD28(-/-) or CD28(+/+) T cells were transplanted into sublethally irradiated (750 cGy), MHC class-I incompatible (B6 x bm1) F1 recipients. With CD28(-/-) cells, 25% of the recipients died at a median of 41 days compared with 100% at a median of 15 days with CD28(+/+) cells (P < . 001). (B6 x bm12)F1 and (B6 x bm1)F1 mice surviving after transplantation of CD28(-/-) cells recovered thymocytes, T cells, and B cells in numbers and function comparable with that of irradiation-control F1 mice. We conclude that CD28 contributes to the pathogenesis and the severity of GVHD. Our results suggest that the severity of GVHD could be decreased by the administration of agents that block CD28 function in T lymphocytes.
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PMID:Role of CD28 in acute graft-versus-host disease. 976 84

We previously used peripheral newborn blood (NBB) as a possible in vivo experimental model for cord blood (CB) transplantation and showed that B10.D2 NBB cells successfully reconstituted adult (DBA/2 x B10.D2)F1 mice without causing graft-versus-host disease (GVHD), probably because of their phenotypic and functional immaturity. Here we investigated the influence of T-cell maturation occurring in NBB cells during the early postbirth period on the degree of engraftment, the incidence of GVHD, and the graft-versus-leukemia (GVL) potential. These parameters were compared in recipients grafted with bone marrow (BM) cells. We observed an increased percentage of CD4(+) mature T cells accompanied by the acquisition of proliferative responses to phytohemagglutinin (PHA) and to allogeneic cells of day-5 NBB cells. The capacity of day-2 NBB to engraft was moderately reduced and recipients developing GVHD were occasionally observed after the graft of day-5 NBB cells. No GVL effect was evidenced regardless of the time of postbirth blood collection. However, the GVL effect can be obtained by the delayed infusion of donor mature T cells to recipients grafted with day-0 NBB, without causing GVHD. In contrast, the same protocol applied to mice grafted with BM cells induced GVHD mortality of all recipients. Interleukin (IL)-10 but not IL-2 messenger RNA was expressed in NBB cells as opposed to BM cells. These findings suggest that, in terms of GVHD incidence, delayed infusion of mature T cells as post-transplant tumor immunotherapy would be more effective when applied after CB than after BM transplantation.
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PMID:Graft-versus-host disease and graft-versus-leukemia effect in mice grafted with peripheral newborn blood. 980 91

It has been reported that a dramatic decrease in the number of thymocytes (thymic atrophy) in mice suffering from acute graft-versus-host disease (GVHD) is ascribed to glucocorticoids. In this study, we examined the possibility that cellular immune responses may thus be involved in thymic atrophy. In contrast to chronic GVHD mice, acute GVHD (C57BL/6 X DBA/2) F1 (BDF1) hybrid mice, which were injected intravenously with both spleen and lymph node cells from C57BL/6 mice, showed a dramatic decrease in the number of CD4 CD8 double-positive thymocytes 2 or 3 weeks after the induction of GVHD. A flow cytometric analysis revealed the donor-derived T cells with either CD4 or CD8 molecules to infiltrate the thymus of the mice undergoing acute GVHD for 10 days. In a cytolytic assay, such thymus-containing cells exhibited a cytolytic activity specific to the host cells. In addition, anti-H-2d cytolytic T cells showed a high level of cytolytic activity against BDF1 (H-2bXd) thymocytes, whereas they also showed a low level of cytolytic activity against C57BL/6 (H-2b) thymocytes, thus suggesting that the thymus-infiltrating donor-derived T cells killed the host thymocytes through both anti-H-2d-specific and non-specific mechanisms. Interestingly, a flow cytometric analysis revealed both the percentage and the absolute cell number of host-derived NK1.1+ CD3+ cells to increase in the thymus of mice suffering from acute GVHD for 10 days. In addition, they also showed the cytolytic activity against YAC-1 cells and the mRNA expression of interleukin-12 (IL-12) in the thymus to be also significantly augmented on day 7 after the induction of acute GVHD. Collectively, our results indicate that the cellular immune responses such as donor cytotoxic T lymphocytes and host NK1.1+ T cells are therefore involved in the thymic atrophy of mice suffering from acute GVHD.
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PMID:Involvement of both donor cytotoxic T lymphocytes and host NK1.1+ T cells in the thymic atrophy of mice suffering from acute graft-versus-host disease. 982 83

This study demonstrates that systemic interleukin 2 (IL-2) can decrease the homing of syngeneic immune T cells to the target organ of metastases and accelerate unwanted side effects of allogeneic immune T cells. As a tumor system, we used the well-characterized highly aggressive DBA/2 mouse leukemia ESb and its less aggressive adhesion variant, ESb-MP. Systemic IL-2 treatment was performed with recombinant human interleukin-2 (Proleukin), which was slowly released via an implanted osmotic pump or was modified with polyethylene glycol (PEG-IL-2) to achieve constant plasma levels. Allogeneic B10.D2 antitumor immune spleen cells (ISPL cells) exerted strong graft-versus-leukemia (GvL) reactivity after adoptive transfer into late-stage ESb-MP tumor-bearing DBA/2 mice. Mls(a) superantigen-reactive vbeta6 donor T cells were not eliminated or tolerized by in vivo priming with the tumor cells and were present in active proliferation in liver infiltrates. When exogenous PEG-IL-2 or Proleukin was applied in addition to ISPL cells in such mice, the strong GvL-mediated protective immunity was converted into a fatal graft-versus-host disease. IL-2 treatment alone had no toxic effect and caused a moderate protection effect in the absence of an effect on local tumor growth. Potentiation of GvH reactivity of B10.D2 ISPL by PEG-IL-2 was proven in non-tumor-bearing DBA/2 mice, in which graft-versus-host disease was characterized by: (a) heavy hepatic lymphocytic infiltration, (b) irreversible increase of serum glutamate-oxalacetate-transaminase and glutamate-pyruvate-transaminase levels, (c) weight loss, and (d) death. Antagonistic effects of systemic IL-2 on GvL were observed with syngeneic DBA/2 anti-ESb immune peritoneal effector cells (PECs). There was a detrimental effect of systemic IL-2 on liver target organ infiltration by immune T cells causing, at day 6 after transfer, a drop from 20-30 CD4 or CD8 T cells per liver lobule in the PEC group to <5 in the PEC plus IL-2 group. The results emphasize the importance of a better understanding of IL-2 function in vivo and of its interaction with immune cell function to improve protocols for optimal application in the clinic to achieve maximal GvL effects.
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PMID:Antagonistic effects of systemic interleukin 2 on immune Tcell-mediated graft-versus-leukemia reactivity. 982 26

We screened various mouse strains [C57BL/6, BALB/c, DBA/2, CBA/Ca, (CBAxC57L/6)F1, SJL, C3H] for induction of peripheral immune tolerance. Only CBA/Ca mice treated with anti-CD4 + CD8 monoclonal antibodies and grafted with allogeneic skin showed long-term graft survival (150 to >200 days). Interestingly, T cells from the tolerant CBA/Ca mice rejected bone marrow/spleen cells of the skin graft donor strain and caused lethal graft-versus-host disease when transplanted to the donor strain. Furthermore, peripheral tolerance was easily broken: CBA/Ca mice could be reactivated to reject their tolerated grafts via immunization with (graft donor x recipient strain)F1 bone marrow cells. Thus, in contrast to the generalized nature of central tolerance, our experiments show that peripheral immune tolerance is strain dependent and locally restricted to graft tissue.
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PMID:Analysis of peripheral immune tolerance uncovers a mouse strain-dependent in situ type of graft tolerance. 993 96

Allogeneic bone marrow transplantation (allo-BMT) is associated with both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect. In the present study, we examined the contribution of cytotoxic effector mechanisms, which are mediated by tumor necrosis factor-alpha (TNF-alpha), Fas ligand (FasL), or perforin, to GVHD and GVL effect in a murine BMT model. Bone marrow cells plus spleen cells (BMS) from wild-type, FasL-defective, or perforin-deficient donors were transferred into lethally irradiated recipients in the parent (C57BL/6) to F1 (C57BL/6 x DBA/2) BMT model with or without prior inoculation of DBA/2 leukemia L1210 or P815 mast cytoma cells. The effect of anti-TNF-alpha antibody administration was also examined. Whereas the defect or blockade of each cytotoxic pathway could ameliorate lethal acute GVHD, the GVL effect was differentially affected. The wild-type BMS recipients died of acute GVHD within 50 days without residual leukemia cells. The FasL-defective BMS recipients showed 60%< survival over 80 days without acute GVHD or residual leukemia cells. Administration of anti-TNF-alpha antibody resulted in early leukemia relapse and the recipients died within 25 days with massive leukemia infiltration in the liver. The perforin-deficient BMS recipients died within 60 days with residual leukemia cells. These results suggest that blockade of the Fas/FasL pathway could be used for ameliorating GVHD without impairing GVL effect in allo-BMT.
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PMID:Graft-versus-leukemia effect and graft-versus-host disease can be differentiated by cytotoxic mechanisms in a murine model of allogeneic bone marrow transplantation. 1019 54

In our model of murine BMT, the lethal GVHD which develops against DBA/2 host incompatible minor histocompatibility antigens (mHAgs) can be prevented by donor preimmunization before grafting. Recipient mice become long survivors (LS mice) and tolerant to host mHAgs. However, a GVL effect is preserved and mediated by CD8+ CTL able to kill P815 tumor cells in vitro and in vivo. To explain why a GVL exists without GVHD, we compared the CTL activity of LS and B10.D2 donor mice after immunization with DBA/2 spleen cells or with P815 cells. Experimental results indicated that: (1) the level of cytotoxicity for H-2b incompatible cells was similar in LS and B10.D2 mice; (2) CTL recognizing host DBA/2 mHAgs, whose expression is restricted to the spleen or is shared between spleen and P815 cells, were partially unresponsive in LS mice; (3) P815 injection into LS mice predominantly generated CTL specific for antigens restricted to P815 cells, the repertoire of which was not tolerized. Characterization of TCR beta chain showed that the diversity of Vbeta and Jbeta usage by CD8+ T cells activated after P815 injection is considerably restricted in LS mice, compared to B10.D2 donor mice. These results indicated that the GVL effect in LS mice involved mainly T cells specific for tissue-restricted antigens expressed on P815 cells and not on normal DBA/2 spleen cells. In addition, the absence of GVHD may be attributed to the unresponsiveness of CD8+ CTL specific for host mHAgs expressed on DBA/2 spleen cells.
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PMID:CD8+ cytotoxic T cell repertoire implicated in grafts-versus-leukemia effect in a murine bone marrow transplantation model. 1033 53

Despite contemporary typing procedures for bone marrow transplantation (BMT), graft-versus-host disease (GVHD) continues to be a major complication of transplants performed between MHC-matched donors and recipients. Although GVHD can be alleviated by T cell depletion, this procedure increases the risk of graft failure and leukemic relapse and therefore is not a solution to the GVHD problem. The high degree of variation in the intensity of GVHD observed in different patients suggests that multiple non-MHC genetic factors influence GVHD severity. We hypothesize that, in addition to minor histocompatibility antigen disparities, polymorphisms in genes encoding immunologic effector molecules may be important factors influencing GVHD development. This study aims to explore this hypothesis by identifying non-MHC genes that influence the outcome of BMT in a murine model. In this model, B10.D2 donor leukocytes cause acute GVHD in (C57BL/6xDBA/2)F1 (B6D2F1) recipients, whereas DBA/2 donor leukocytes do not. To date, a locus on chromosome 1 has been identified as influencing the severity of GVHD in this model. Our current study shows that a locus on chromosome 2 acts independently of the chromosome 1 locus to also influence GVHD severity in this model. The region of chromosome 2 implicated in our study contains genes encoding beta2-microglobulin, the minor histocompatibility antigen H-3 and the pro-inflammatory cytokine IL-1.
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PMID:A locus on chromosome 2 influences the development of acute graft-versus-host disease in a murine model. 1038 59


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