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)

Retroviral vectors encoding the herpes simplex thymidine kinase gene have been used to render T cells sensitive to the prodrug ganciclovir. Such genetically modified T cells have been used in clinical trials for their graft-versus-leukaemia effects following allogeneic haematopoietic stem cell transplantation. In the event of graft-versus-host disease (GVHD) the cells were susceptible to elimination through exposure to ganciclovir. We have investigated the impact of T-cell activation, required for successful retrovirus-mediated gene transfer, on T-cell receptor repertoire profile, subset distribution and antiviral potential. Using a combination of antibodies against CD3 and CD28, T cells were transduced at high efficiency when exposed to retrovirus between 48 and 72 h later. Lymphocytes had undergone up to seven cycles of cell division by the end of the procedure. Although the T-cell receptor Vbeta repertoire was not altered after retroviral transduction, there were notable shifts in subset profiles with an increased proportion of CD45RO cells in transduced populations. T cells continued to proliferate for several days after transduction and were difficult to sustain under the extended culture conditions required to generate virus-specific T cells. These observations may explain the lower than expected levels of GVHD and poor antiviral immunity reported in recent trials.
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PMID:The impact of retroviral suicide gene transduction procedures on T cells. 1461 77

Herpes simplex virus (HSV) infection in adult patients who underwent cord blood transplantation (CBT) from unrelated donors was studied. None of nine HSV-seronegative patients developed HSV disease after CBT. Of 28 HSV-seropositive patients, seven (25%) developed HSV disease at a median of 92 days after CBT (range, 52-239 days). The cumulative incidence of HSV disease in HSV-seropositive patients was 27% at 12 months after CBT. The manifestations of HSV disease included gingivostomatitis (three patients), herpes labialis (two patients), localized herpes facialis of the nose (one patient), and disseminated eczema herpeticum (one patient). HSV disease recurred in two patients as gingivostomatitis and disseminated eczema herpeticum. All the patients responded to antiviral therapy. The presence of grade II-IV acute graft-versus-host disease (GVHD) was significantly associated with a higher rate of HSV disease after CBT (51 vs 8%, P=0.015). These results suggest that the recovery of HSV-specific immune responses is delayed in patients who develop grade II-IV acute GVHD after CBT.
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PMID:Herpes simplex virus infection in adult patients after unrelated cord blood transplantation: a single-institute experience in Japan. 1464 49

To determine the graft-versus-leukemia effect after hematopoietic stem cell transplantation (HSCT), we studied 199 patients with acute lymphoblastic leukemia who underwent transplantation at Huddinge University Hospital between 1981 and 2001. Seventy-four patients were in first complete remission (CR1), and 125 were in later stages of the disease. Most patients had an HLA-identical sibling donor. Conditioning consisted mainly of total body irradiation and cyclophosphamide, and graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. Acute GVHD developed in 143 patients and chronic GVHD in 67. The 5-year probability of relapse and relapse-free survival (RFS) were 32% and 49%, respectively, in patients in CR1, as compared with 53% and 33% in those with more advanced disease. In the multivariate risk factor analysis of relapse, we found that the absence of chronic GVHD (P<.001), absence of herpes simplex virus infection after HSCT (P=.003), combination prophylaxis with methotrexate and cyclosporine (P=.01), and >6 weeks from the diagnosis to CR (P=.025) were independent risk factors for relapse after HSCT. Factors associated with a better relapse-free survival were chronic GVHD (P<.001), ABO blood group mismatch (P=.006), younger patient age (P=.01), and an HLA-matched donor (P=.01). The association between herpes simplex virus infection and a low frequency of relapse is a new observation and may indicate that viral antigens play a role in the induction of an antileukemic effect.
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PMID:Graft-versus-host disease is associated with a lower relapse incidence after hematopoietic stem cell transplantation in patients with acute lymphoblastic leukemia. 1499 85

Graft versus host disease (GVHD) is a T cell mediated phenomenon that arises following allogeneic haematopoietic stem cell transplantation, and may be particularly severe in the context of human leukocyte antigen (HLA) mismatched procedures. Although GVHD can be largely abrogated through T cell depletion, such measures result in loss of graft potency and reduced anti-viral and anti-leukaemic effects. The genetic modification of T cells to carry a suicide gene mechanism has been advocated as means of allowing T cells to be harnessed for their beneficial effects, and safely eliminated in the event of significant GVHD. The feasibility of the strategy has been demonstrated in clinical studies using T cells modified by retroviral transduction to encode the herpes simplex thymidine kinase (HSVTK) gene to treat patients with haematological malignancies. However, a number of limitations associated with current protocols have become apparent. Most notably, the process of retroviral transduction, which requires pre-activation of T cells, appears to impair subsequent functional potential. Efforts are now directed towards circumventing the pre-activation requirements of retroviral vectors by using alternative lentiviral systems, in association with improved suicide gene/prodrug combinations.
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PMID:T cell suicide gene therapy to aid haematopoietic stem cell transplantation. 1563 16

Infections with herpesviruses were frequent after bone marrow transplantation (BMT) before the preventive use of antiviral drugs, suggesting a deficit of innate immunity. A retrospective phenotypical and functional study was carried out on 25 patients 1-36 months after allogeneic BMT. Leukocyte counts followed a normal reconstitution, including natural killer (NK) cells and monocytes. Plasmacytoid dendritic cell (PDC) counts increased steadily, although they remained below normal values after 2 years. Most patients produced less interferon- alpha/beta (IFN-alphabeta) in vitro than healthy controls after infection with herpes simplex virus type 1 (HSV-1), whereas they responded normally to Sendai virus (SV). In addition, 6 patients had biologic signs of infection with herpesviruses, confirming a specific immunologic deficit against these viruses. IFN production was not correlated to PDC counts or to the occurrence of graft-versus-host disease (GVHD). Because all patients were under immunosuppressive treatment, we investigated the effect of drugs on IFN production by mononuclear cells. Glucocorticoids and cyclosporine A inhibited IFN production by infected leukocytes, with a predominant action on HSV-1-infected PDC. The inability of transplanted patients to mount an efficient immune response to herpesviruses may be partly related to drug toxicity toward cells of the innate immune system.
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PMID:Plasmacytoid dendritic cell reconstitution following bone marrow transplantation: subnormal recovery and functional deficit of IFN-alpha/beta production in response to herpes simplex virus. 1576 87

Varicella-zoster virus (VZV) disease occurs in 30% of allogeneic hematopoietic cell transplant recipients who had a history of VZV infection. A safe and effective prevention strategy has not been established. In a double-blind controlled trial, 77 hematopoietic cell transplant recipients at risk for VZV reactivation were randomized to acyclovir 800 mg twice daily or placebo given from 1 to 2 months until 1 year after transplantation. VZV disease at 1 year was the primary end point; VZV disease after discontinuation of prophylaxis, VZV-specific T-cell immunity, herpes simplex virus (HSV) infection, cytomegalovirus (CMV) disease, survival, and safety were secondary end points. Acyclovir significantly reduced VZV infections at 1 year after transplantation (HR, 0.16; 95% CI, 0.035-0.74; P = .006). In the post-intervention observation period, this difference was not statistically significant (2 years: HR, 0.52; 95% CI, 0.21-1.3; 5 years: HR, 0.76; 95% CI, 0.36-1.6). There was no statistically significant difference in reconstitution of VZV-specific T-helper cell responses, HSV infections, CMV disease, chronic graft-versus-host disease, and overall survival between the groups. Acyclovir was well tolerated. Post-study VZV disease predominantly occurred in patients with continued need for systemic immunosuppression. In conclusion, acyclovir effectively and safely prevents VZV disease during the first year after hematopoietic cell transplantation. Periods of prophylaxis longer than 12 months may be beneficial for those hematopoietic cell transplant recipients on continued immune suppression.
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PMID:Long-term acyclovir for prevention of varicella zoster virus disease after allogeneic hematopoietic cell transplantation--a randomized double-blind placebo-controlled study. 1628 39

The introduction of an inducible suicide gene such as the herpes simplex virus thymidine kinase (HSV-TK) might allow exploitation of the antitumor activity of donor T cells after allogeneic hematopoietic cell transplantation (HCT) without graft versus host disease. However, HSV-TK is foreign, and immune responses to gene-modified T cells could lead to their premature elimination. We show that after the infusion of HSV-TK-modified donor T cells to HCT recipients, CD8+ and CD4+ T-cell responses to HSV-TK are rapidly induced and coincide with the disappearance of transferred cells. Cytokine flow cytometry using an overlapping panel of HSV-TK peptides allowed rapid detection and quantitation of HSV-TK-specific T cells in the blood and identified multiple immunogenic epitopes. Repeated infusion of modified T cells boosted the induced HSV-TK-specific T cells, which persisted as memory cells. These studies demonstrate the need for nonimmunogenic suicide genes and identify a strategy for detection of CD4+ and CD8+ T-cell responses to transgene products that should be generally applicable to monitoring patients on gene therapy trials. The potency of gene-modified T cells to elicit robust and durable immune responses imply this approach might be used for vaccination to elicit T-cell responses to viral or tumor antigens.
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PMID:Analysis of transgene-specific immune responses that limit the in vivo persistence of adoptively transferred HSV-TK-modified donor T cells after allogeneic hematopoietic cell transplantation. 1628 41

In allogeneic hematopoietic cell transplantation (allo-HCT), the immune recognition of host antigens by donor T lymphocytes leads to a beneficial graft-versus-leukemia (GvL) effect as well as to life-threatening graft-versus-host disease (GvHD). Genetic modification of T lymphocytes with a retroviral vector (RV) expressing the herpes simplex virus-thymidine kinase (TK) suicide gene confers selective sensitivity to the prodrug ganciclovir (GCV). In patients, the infusion of TK+ lymphocytes and the subsequent administration of GCV resulted in a time-wise modulation of antihost reactivity for a GvL effect, while controlling GvHD. Because activation required for genetic modification with RV may reduce antihost reactivity, we investigated the requirements for maximizing the potency of human TK+ lymphocytes. Whereas T-cell receptor triggering alone led to effector memory (EM) TK+ lymphocytes, the addition of CD28 costimulation through cell-sized beads resulted in the generation of central memory (CM) TK+ lymphocytes. In a quantitative model for GvHD using nonobese diabetic/severely combined immunodeficient mice, CM TK+ lymphocytes were more potent than EM TK+ lymphocytes. GCV administration efficiently controlled GvHD induced by CM TK+ lymphocytes. These results warrant the clinical investigation of CM suicide gene-modified human T lymphocytes for safe and effective allo-HCT.
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PMID:Suicide gene therapy of graft-versus-host disease induced by central memory human T lymphocytes. 1629 1

Allogeneic stem cell transplantation is often complicated by reactivation of herpesviruses. Mesenchymal stem cells (MSC) are immunomodulatory and may be used to treat graft-versus-host disease. We investigated if herpesviruses infect and can be transmitted by MSC, and if MSC suppress immune responses to various infectious agents. Mesenchymal stem cells from healthy seropositive donors were evaluated with polymerase chain reaction for the most common herpesviruses: cytomegalovirus (CMV), herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2, Epstein-Barr virus (EBV) and varicella zoster virus. The cytopathological effect (CPE) was investigated and viral antigens analyzed by immunofluorescence after in vitro exposure to CMV, HSV-1 and EBV. We also studied MSC effect on lymphocyte stimulation induced by various infectious agents. No viral DNA could be detected in MSC isolated from healthy seropositive individuals. However, a CPE was noted and intracellular viral antigens detected after infection in vitro by CMV and HSV-1, but not by EBV. The CMV and HSV-1 infections were productive. Lymphocyte proliferation by herpesviruses, candida mannan and protein A from Staphylococcus aureus was suppressed by MSC. The data indicate that the risk of herpesvirus transmission by transplantation of MSC from healthy seropositive donors is low. However, MSC may be susceptible to infection if infused in a patient with CMV or HSV-1 viremia. MSC transplantation may compromise the host's defense against infectious agents.
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PMID:Mesenchymal stem cells are susceptible to human herpesviruses, but viral DNA cannot be detected in the healthy seropositive individual. 1660 97

Donor T lymphocytes genetically engineered to express a "suicide gene" to facilitate negative selection represent a promising strategy for the management of graft-versus-host disease occurring after allogeneic hematopoietic cell transplantation (HCT). For this purpose, the herpes simplex virus thymidine kinase (HSV-tk) gene, although well studied, has limitations. Cytosine deaminase (CD), an alternative gene for negative selection, converts 5-fluorocytosine (5-FC) to the toxic metabolite 5-fluorouracil (5-FU). Sensitivity of cells to 5-FU can be further increased by expression of uracil phosphoribosyltransferase (UPRT), which catalyzes the conversion of 5-FU to 5-fluorouridine monophosphate. By using a chimeric gene (NG/CD) expressing the truncated human nerve growth factor receptor (NGFR) for positive selection fused to the Saccharomyces cerevisiae CD gene, we investigated strategies to achieve optimal T cell eradication by CD and UPRT expression, utilizing a single retroviral vector. Three vector strategies were compared on the basis of NGFR expression by flow cytometry, western analysis, and enzymatic activity. A construct (NG/CDiU) expressing UPRT and NG/CD, using a bicistronic message, provided the greatest UPRT activity and killing, reducing the lethal dose of 5-FC sufficient to eradicate 90% of cells from 38.7 microg/ml (300 microM) (NG/CD expression alone) to 0.13 microg/ml (1 microM). This approach provides an effective alternative to the HSV-tk system for eradication of donor T lymphocytes after allogeneic HCT.
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PMID:Coexpression of the uracil phosphoribosyltransferase gene with a chimeric human nerve growth factor receptor/cytosine deaminase fusion gene, using a single retroviral vector, augments cytotoxicity of transduced human T cells exposed to 5-fluorocytosine. 1671 9


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