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)

Prolonged immunodeficiency after allogeneic bone marrow transplantation (BMT) causes significant morbidity and mortality from infection. This study examined in murine models the effects of interleukin-7 (IL-7) given to young and middle-aged (9-month-old) recipients of major histocompatibility complex (MHC)-matched or -mismatched allogeneic BMT. Although administration of IL-7 from day 0 to 14 after syngeneic BMT promoted lymphoid reconstitution, this regimen was ineffective after allogeneic BMT. However, IL-7 administration from day 14 (or 21) to 27 after allogeneic BMT accelerated restoration of the major lymphoid cell populations even in middle-aged recipients. This regimen significantly expanded donor-derived thymocytes and peripheral T cells, B-lineage cells in bone marrow and spleen, splenic natural killer (NK) cells, NK T cells, and monocytes and macrophages. Interestingly, although recipients treated with IL-7 had significant increases in CD4(+) and CD8(+) memory T-cell populations, increases in naive T cells were less profound. Most notable, however, were the observations that IL-7 treatment did not exacerbate graft-versus-host disease (GVHD) in recipients of an MHC-matched BMT, and would ameliorate GVHD in recipients of a MHC-mismatched BMT. Nonetheless, graft-versus-leukemia (GVL) activity (measured against 32Dp210 leukemia) remained intact. Although activated and memory CD4(+) and CD8(+) T cells normally express high levels of IL-7 receptor (IL-7R, CD127), activated and memory alloreactive donor-derived T cells from recipients of allogeneic BMT expressed little IL-7R. This might explain the failure of IL-7 administration to exacerbate GVHD. In conclusion, posttransplant IL-7 administration to recipients of an allogeneic BMT enhances lymphoid reconstitution without aggravating GVHD while preserving GVL.
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PMID:Administration of interleukin-7 after allogeneic bone marrow transplantation improves immune reconstitution without aggravating graft-versus-host disease. 1156 14

Allogeneic hematopoietic stem cell transplantation (AHSCT) leads to a prolonged state of immunodeficiency characterized by low peripheral naive T-cell counts. To identify the mechanisms leading to this defect we quantitatively and qualitatively analyzed thymic function through quantification of T-cell receptor excision circle (TREC) frequencies (both the signal-joint TREC [sjTREC] and 6 different DbetaJbeta TRECs, by-products of T-cell receptor [TCR] alpha and beta gene rearrangement, respectively), in conjunction with immunophenotype and spectratype analyses in a cohort of patients sampled from 1 to 10 years following AHSCT. In this cohort, reduced thymic function was associated only with ongoing clinical chronic graft-versus-host disease (cGVHD). Nonetheless, the diversity of thymic production remained unchanged irrespective of the patient's cGVHD status. Interestingly, increased homeostatic proliferation was found in the naive T-cell compartment of cGVHD- patients who underwent transplantation. However, reduced expression of both the interleukin-7 receptor alpha (IL-7Ralpha) (CD127) chain and the antiapoptotic protein Bcl-2 was observed. Taken together, these data indicate that the inability to reconstitute the naive T-cell compartment for several years after AHSCT, in the absence of cGVHD, is a consequence of impaired naive T-cell survival rather than thymic dysfunction.
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PMID:Evidence for adequate thymic function but impaired naive T-cell survival following allogeneic hematopoietic stem cell transplantation in the absence of chronic graft-versus-host disease. 1293 79

We used clinically relevant murine allogeneic bone marrow transplantation (BMT) models to study the mechanisms by which IL-7 administration can improve posttransplant peripheral T cell reconstitution. After transplant we could distinguish two populations of mature donor T cells: (a) alloreactive T cells with decreased expression of CD127 (IL-7 receptor alpha chain) and (b) nonalloreactive T cells, which express CD127 and undergo homeostatic proliferation. IL-7 administration increased the homeostatic proliferation of nonalloreactive T cells, but had no effect on alloreactive T cells and the development of graft-versus-host disease. Allogeneic transplant of purified hematopoietic stem cells and adoptive transfer of thymocytes into lethally irradiated hosts suggested that recent thymic emigrants can undergo homeostatic proliferation and acquire a memory-like phenotype. We found by BrdU pulse-chase, cell cycle, and annexin V analyses that IL-7 administration has significant proliferative and antiapoptotic effects on posttransplant peripheral T cells. We conclude that homeostatic expansion is important for T cell reconstitution after allogeneic BMT and involves both transferred mature T cells and recent thymic emigrants. Apart from its thymopoietic effects, IL-7 promotes peripheral T cell reconstitution through its selective proliferative and antiapoptotic effects on nonalloreactive and de novo-generated T cells, but has no effect on alloreactive T cells.
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PMID:IL-7 enhances peripheral T cell reconstitution after allogeneic hematopoietic stem cell transplantation. 1452 46

Regulatory T cells (Treg) have been identified as playing a pivotal role in the control of tolerance and in the suppression of pathologic immune responses in autoimmune diseases, transplantation, and graft-versus-host disease. Treg expanded ex vivo by dendritic cells could be potential reagents to promote antigen-specific tolerance in vivo. However, in vivo studies have been carried out mostly in rodents and will need validation in primates before clinical application. We characterized macaque dendritic cell derived either from bone marrow with and without prior CD34+ cell selection (BMDC), or from CD14+ peripheral blood mononuclear cells (Mo-DC). We demonstrate that with a semi-mature phenotype, BMDC are superior to Mo-DC in their capacity to expand freshly isolated allogeneic macaque CD4+ CD25+ CD127- Foxp3+ Treg in vitro in the presence of interleukin-2. Moreover, the expanded Treg maintain their phenotype and suppressive activity. These data provide a step toward the use of macaque dendritic cell to expand Treg for future preclinical testing.
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PMID:Superiority of bone marrow-derived dendritic cells over monocyte-derived ones for the expansion of regulatory T cells in the macaque. 1847 95

Regulatory T cells (Treg) play a pivotal role in the control of graft-versus-host disease (GVHD) and might also influence the graft-versus-tumor effect after allogeneic stem cell transplantation. We assessed this role after donor lymphocyte infusions (DLIs) by quantifying Treg in DLI products, using the CD25, Foxp3 but also the recently identified CD127 Treg markers. Compared with others, patients in durable complete remission of their malignancy after DLI had received a lower number of FoxP3CD25, FoxP3CD127, or CD4CD127 Treg cells (P=0.04). The CD4CD127 Treg content of DLI remained significantly correlated with the hematologic response in multivariate analysis (P=0.05). Treg may thus inhibit graft-versus-tumor effect after DLI, a setting where the antitumoral effect observed is only driven by T-cell-mediated cytotoxicity, independently of any other associated treatment. In comparison with the intracytoplasmic Foxp3 marker, the membranous CD4CD127 phenotype of Treg could be particularly relevant to manipulate this cell-population, to increase the antitumoral response in strategies of allogeneic or autologous immunotherapy.
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PMID:Donor regulatory T cells identified by FoxP3 expression but also by the membranous CD4+CD127low/neg phenotype influence graft-versus-tumor effect after donor lymphocyte infusion. 1883 7

Graft-versus-host disease is the main complication after hematopoietic stem cells transplantation (HSCT). Non-HLA genotypes, such as cytokines, have been investigated for their potential roles in the occurrence and severity of GVHD as well as for their contribution to overall transplant-related mortality and survival. IL-7 which is secreted by bone marrow stromal cells plays an important role in the development and survival of T cells. Its effect is mediated via interleukin 7 receptor (IL7R). This study investigates the possible links between IL-7alphaR single nucleotide polymorphisms (+510 C/T, +1237 A/G, +2087 T/C and +3110A/G) and transplant outcomes among 116 recipients of HSCT. Genotypes were determined using polymerase chain reaction-sequence-specific primers. No significant differences were observed between the genotypic distributions of IL-7alphaR polymorphisms and incidence of acute or chronic graft versus host disease. Additional studies with larger sample are necessary to further define the influence of IL-7alphaR on the immune response after bone marrow transplantation.
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PMID:Interleukin-7 receptor-alpha gene polymorphisms in bone marrow transplant recipients. 1925 27

Although CD4(+)/CD25(+) T regulatory cells (T(regs)) are a potentially powerful tool in bone marrow transplantation, a prerequisite for clinical use is a cell-separation strategy complying with good manufacturing practice guidelines. We isolated T(regs) from standard leukapheresis products using double-negative selection (anti-CD8 and anti-CD19 monoclonal antibodies) followed by positive selection (anti-CD25 monoclonal antibody). The final cell fraction (CD4(+)/CD25(+)) showed a mean purity of 93.6% +/- 1.1. Recovery efficiency was 81.52% +/- 7.4. The CD4(+)/CD25(+bright) cells were 28.4% +/- 6.8. The CD4(+)/CD25(+) fraction contained a mean of 51.9% +/- 15.1 FoxP3 cells and a mean of 18.9% +/- 11.5 CD127 cells. Increased FoxP3 and depleted CD127 mRNAs in CD4(+)CD25(+)FoxP3(+) cells were in line with flow cytometric results. In Vbeta spectratyping the complexity scores of CD4(+)/CD25(+) cells and CD4(+)/CD25(-) cells were not significantly different, indicating that T(regs) had a broad T cell receptor repertoire. The inhibition assay showed that CD4(+)/CD25(+) cells inhibited CD4(+)/CD25(-) cells in a dose-dependent manner (mean inhibition percentages: 72.4 +/- 8.9 [ratio of T responder (T(resp)) to T(regs), 1:2]; 60.8% +/- 20.5 (ratio of T(resp) to T(regs), 1:1); 25.6 +/- 19.6 (ratio of T(resp) to T(regs), 1:0.1)). Our study shows that negative/positive T(reg) selection, performed using the CliniMACS device and reagents, enriches significantly CD4(+)CD25(+)FoxP3(+) cells endowed with immunosuppressive capacities. The CD4(+)CD25(+)FoxP3(+) population is a source of natural T(reg) cells that are depleted of CD8(+) and CD4(+)/CD25(-) reacting clones which are potentially responsible for triggering graft-versus-host disease (GvHD). Cells isolated by means of this approach might be used in allogeneic haematopoietic cell transplantation to facilitate engraftment and reduce the incidence and severity of GvHD without abrogating the potential graft-versus-tumour effect.
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PMID:Immunomagnetic isolation of CD4+CD25+FoxP3+ natural T regulatory lymphocytes for clinical applications. 1929 55

We investigated efficacy and toxicity of lenalidomide in 24 heavily pretreated myeloma patients with a median age of 59 years (range: 37-70) and relapse after allo-SCT. Lenalidomide was given at a dose of 15 mg (n=4), or 25 mg (n=20), orally once daily on day 1 to day 1 every 28 days, with (n=20) or without (n=4) DHAP. The median number of lenalidomide cycles was five (range: 2-17). Major side effects were leukopenia (grade 4: 4%, grade 3: 21% and grade 2: 17%) and thrombocytopenia (grade 3: 17% and grade 2: 29%); infectious complications were observed in 50%. Non-hematological toxicity consisted of muscle cramps (n=9), fatigue (n=5) and constipation (n=2). Mild grade I-II GVHD was seen in three patients. Response was achieved in 66%: CR in 8%, VGPR in 8%, PR in 50% and SD in 13%. The median time to progression was 9.7 months (95% confidence interval (CI): 7.5-11.9), and median OS was 19.9 months (95% CI: 17.3-22.5). Immunomonitoring after lenalidomide showed significant increase of activated NK (NKp44(+)) and T (HLA-DR(+)) cells, as well as regulatory T cells (CD4(+), CD25(+), CD127(lo)), supporting an immunomodulating anti-myeloma effect of lenalidomide.
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PMID:Lenalidomide as salvage therapy after allo-SCT for multiple myeloma is effective and leads to an increase of activated NK (NKp44(+)) and T (HLA-DR(+)) cells. 1958 25

Peripheral blood stem cell transplantation (PBSCT) is an alternative to bone marrow transplantation (BMT). Although CD4(+)CD25(+)CD127(lo) regulatory T cells (Tregs) have been shown to play important roles in the control of T cell reactivity, the Treg contents of both graft types have not been analyzed comparatively to date. We report herein that Treg frequencies are significantly reduced in PBSC compared to BM transplants. Furthermore, most Tregs from PBSC transplants are CD62L(lo), a phenotype reported to have poor suppressor activity. Both granulocyte-colony stimulating factor (G-CSF) administration and leukapheresis were found to contribute to the loss of CD62L(+) Tregs. Although higher T cell numbers are infused in PBSCT than in BMT, it is possible that the reduced Treg content of PBSC transplants may represent 1 factor contributing to the higher risk of GVHD reported after PBSCT.
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PMID:Reduced frequency of regulatory T cells in peripheral blood stem cell compared to bone marrow transplantations. 1988 75

Graft-versus-host disease (GVHD) is a frequent and life threatening complication of allogeneic haematogenesis stem cell transplantation (aHSCT). The correlation of CD4(+)CD25(+) regulatory T cells (Tregs) in the patients after aHSCT to the occurrence and severity of acute and chronic GVHD (aGVHD and cGVHD) is not fully investigated. Here, we examined the levels of CD4(+)CD25(+) Tregs by assessment of CD4(+)CD25(high) and CD4(+)CD25(+)CD127(low) in peripheral blood, and the levels of serum TGF-beta and TNF-alpha in 56 patients at early immune reconstitution following aHSCT. Our data showed a significant reduction in the frequency of Tregs in patients with grades II-IV aGVHD and extensive cGVHD compared to healthy controls. Moreover, a decreased level of CD4(+)CD25(+) Tregs was correlated to increased severity of GVHD. The levels of CD4(+)CD25(+) Tregs in non-GVHD groups were however significantly higher than that in healthy controls. A significant decrease in the levels of TGF-beta and a significant increase the levels of TNF-alpha was also seen with increased severity of GVHD. This study suggested that measurement of CD4(+)CD25(+) Tregs along with serum TGF-beta and TNF-alpha at early immune reconstruction after aHSCT may indicate the onset and severity of both aGVHD and cGVHD.
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PMID:Decrease of CD4(+)CD25(+) regulatory T cells and TGF-beta at early immune reconstitution is associated to the onset and severity of graft-versus-host disease following allogeneic haematogenesis stem cell transplantation. 2040 84


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