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)

Cord blood is increasingly used for hematopoietic stem cell transplantation since less severe graft-versus-host disease has been reported leading to the notion that cord blood is "naive." Human leucocyte antigen (HLA) class II molecules are expressed throughout B lymphocyte ontogeny (except the plasmocytes), are responsible for antigen presentation, and can also transmit signals. Cord blood B stimulate an allogeneic response, and this property is believed to indicate the presence of a class II-associated peptide. In this study we examined the capacity of cord blood B to transmit signals via HLA-DR. Activation and relocalization of protein kinase C (PKC) isoenzymes alpha and betaII was detected along with tyrosine kinase activation and proliferation. However, in contrast to resting adult B, generation of an intracellular calcium ([Ca++]i) flux and rapid aggregation were not detected. To address the question of whether or not HLA-DR signals throughout B lymphocyte ontogeny, we extended this study to include malignant adult B (B chronic lymphocytic leukemia [B-CLL], B mantle cell lymphoma, and B large cell leukemia). Tyrosine kinase activation and proliferation were observed in all these cell populations, albeit in the absence of [Ca++]i flux or an increase in PKC. HLA-DR therefore transmits signals throughout B lymphocyte ontogeny, although different signaling pathways are initiated in adult vs. fetal vs. malignant B. The lack of intracellular [Ca++]i flux in both cord blood and malignant B lymphocytes may represent a feature of HLA class II signaling at a particular stage of differentiation, although the downregulation of PKC clearly distinguishes between cord blood B and B-CLL.
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PMID:Signal transduction via human leucocyte antigen class II molecules distinguishes between cord blood, normal, and malignant adult B lymphocytes. 969 9

Janus kinase 3 (JAK3) is a cytoplasmic tyrosine kinase required for T cell development and activated by cytokines that utilize the interleukin-2 (IL-2) receptor common gamma chain (gamma(c)). Genetic inactivation of JAK3 is manifested as severe combined immunodeficiency disease (SCID) in humans and mice. These findings have suggested that JAK3 represents a pharmacological target to control certain lymphoid-derived diseases. Here we provide novel evidence that AG-490 potently inhibits the autokinase activity of JAK3 and tyrosine phosphorylation and DNA binding of signal transducer and activator of transcription 5a and 5b (STAT5a/b). Similar inhibitory effects were observed with other cytokines that use gamma(c). AG-490 also inhibited IL-2-mediated proliferative growth in human T cells with an IC50) = 25 microM that was partially recoverable. Moreover, we demonstrate that this inhibitor prevented tetanus toxoid antigen-specific T cell proliferation and expansion but failed to block activation of Zap70 or p56Lck after anti-CD3 stimulation of human T cells. Taken together, these findings suggest that AG-490 inhibits the JAK3-mediated Type II signaling pathway but not the T cell receptor-derived Type I pathway and possesses therapeutic potential for T cell-derived pathologies such as graft-versus-host disease, allergy, and autoimmune disorders.
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PMID:Tyrphostin AG-490 inhibits cytokine-mediated JAK3/STAT5a/b signal transduction and cellular proliferation of antigen-activated human T cells. 1038 Sep 15

Interleukin-12 (IL-12) is an immunoregulatory cytokine that plays an essential role in cell-mediated immunity. It is known to induce T cell apoptosis in in vivo systems such as graft-versus-host disease (GVHD) and experimental autoimmune uveitis (EAU). However, the role of IL-12 in T cell apoptosis in the absence of antigenic stimulation has not been clearly defined. This study was conducted to investigate whether IL-12, in the absence of an antigen, is able to induce T cell apoptosis, and also, which signalling pathways utilized by IL-12 are involved in this process. Our data clearly showed that IL-12 in the absence of an antigen induces apoptosis in T cells. Flow cytometry and ELISA showed FasL up-regulation and increased IFN-gamma synthesis in IL-12 treated T cells, while Fas and TNF-R1 showed little change. Semi-quantitative RT-PCR demonstrated that IL-12 was able to up-regulate TNF-alpha and FasL mRNA expression. Furthermore, IL-12 induced apoptosis was associated with caspase-3, caspase-2, caspase-7, DNA fragmentation factor 45 (DFF45) and Fas associated death domain (FADD) whereas TNF receptor associated death domain (TRADD) and receptor interacting protein (RIP) were not. Inhibition of Janus tyrosine kinase (JAK) was able to suppress IL-12 induced T cell apoptosis. Anti-FasL antibody was able to block IL-12 induced T cell apoptosis. In conclusion, our findings suggest that IL-12 is able to induce T cell apoptosis in the absence of an antigen. In addition, the present data suggest that this process is FasL mediated and caspase-3 dependent. Furthermore, JAK was shown to be involved in this process. These results may have significant implications in the understanding of IL-12 mediated T cell apoptosis.
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PMID:IL-12 plays a significant role in the apoptosis of human T cells in the absence of antigenic stimulation. 1224 79

Eight patients with Philadelphia chromosome-positive (Ph(+)) leukaemia relapsing from stem cell transplantation (SCT) (one syngeneic and seven allogeneic) were treated with the tyrosine kinase inhibitor STI571. Five patients relapsing as chronic myeloid leukaemia (CML) in chronic phase achieved a complete haematological response, with complete and major cytogenetic responses occurring in four and one cases, respectively. One patient became negative for BCR/ABL in the bone marrow. Three patients relapsed as acute leukaemia (two CML in myeloblastic crisis and one Ph(+) acute lymphoblastic leukaemia), all of whom achieved haematological and cytogenetic responses. One patient also became BCR/ABL negative. However, pancytopenia and graft-versus-host disease led to cessation of treatment in the remaining two cases, which was followed by disease recurrence refractory to further STI treatment. Our results showed that Ph(+) leukaemic relapses after SCT might respond well to STI571 therapy.
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PMID:Tyrosine kinase inhibitor STI571 in the treatment of Philadelphia chromosome-positive leukaemia failing myeloablative stem cell transplantation. 1236 58

Recently, a number of medications approved for nondermatologic use have proved useful against dermatologic diseases. This article reviews the dermatologic uses and effects of deferasirox, bortezomib, dasatinib, and cyclosporine eye drops. Deferasirox--an oral iron chelator--could be an effective treatment against porphyria cutanea tarda, hemochromatosis, and pathogens such as mucor that thrive in iron rich environments. Bortezomib, a proteasome inhibitor and multiple myeloma treatment, may be effective against nodular amyloid and has been effectively used against squamous cell carcinoma; although trials demonstrate it is ineffective against metastatic melanoma. Bortezomib has many cutaneous side effects including erythematous plaques or nodules, a generalized morbilliform erythema with ulcerations and fever, purpuric eruptions, leukocytoclastic vasculitis, Sweet's syndrome, and folliculitis. Dasatinib is a multi-targeted tyrosine kinase inhibitor active in vitro against most cell lines containing BCR-ABL mutations that confer resistance to imatinib. Dasatinib is likely to be effective against dermatofibroma sarcoma protuberans and cutaneous acute lymphoblastic leukemia, and has caused panniculitis. Cyclosporine 0.05% ocular emulsion (eye drops) are approved to treat dry eyes including dry eyes caused by collagen vascular disease. Cyclosporine eye drops might also have utility in treating eye pathology of ocular rosacea, atopic keratoconjunctivitis, graft versus host disease, herpes keratitis, chronic sarcoidosis of the conjunctiva, conjunctival manifestations of actinic prurigo, keratitis of keratitis-ichthyosis deafness (KID) syndrome, and lichen planus-related kerato-conjunctivitis. This article speculates that cyclosporine eye drops would also be useful for any disease causing ectropion or eclabion of the eye as well as toxic epidermal necrolysis-related eye pathology (in particular corneal scarring).
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PMID:A review of deferasirox, bortezomib, dasatinib, and cyclosporine eye drops: possible uses and known side effects in cutaneous medicine. 1737 1

Recently, several new classes of agents were developed to treat patients with malignant diseases. This progress has been based on the advances made in our understanding of critical pathways involved in tumor development and growth. Dysregulated processes leading to uncontrolled regulation of proliferation, cell cycle progression, angiogenesis and apoptosis have provided rational targets for novel therapies. Compounds inhibiting protein phosphorylation and signal transduction like tyrosine kinase inhibitors and inhibitors of proteasomal degradation have demonstrated promising results and were approved for the treatment of patients with malignant diseases. However, based on in vitro and in vivo studies, there is now an emerging evidence that these agents can affect the function and differentiation of normal, non-malignant cells like dendritic cells or T lymphocytes, resulting in immunosuppression. In our review we present recent data on the immune regulatory effects of tyrosine kinase inhibitors like imatinib that is approved to treat chronic myeloid leukemias, or inhibitors of FLT3, currently used to treat acute leukemias, as well as proteasome inhibitors and peroxisome proliferator-activated receptor agonists and discuss their possible role and application in the treatment of autoimmune and graft versus host disease.
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PMID:Development of novel compounds to treat autoimmune and inflammatory diseases and graft versus host reactions. 1758 49

Specific immunotherapies for CML patients targeting T cell antigens might eliminate residual CML cells after chemotherapy, in combination with imatinib or other tyrosine kinase inhibitors, and might enhance a specific graft versus leukemia effect after allogeneic stem cell transplantation without aggravating the graft versus host disease. For an effective specific immunotherapy in CML, the use of leukemia-associated antigens (LAAs) with an optimal expression pattern is required. In this work, we review known LAAs which are able to induce specific CD8 positive T cell responses and which are appropriate target structures for immunological targeting of CML cells. Moreover, an overview on LAA-targeted immunotherapeutic approaches for CML patients are given.
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PMID:Leukemia-associated antigens as target structures for a specific immunotherapy in chronic myeloid leukemia. 1828 27

The prognosis for patients with chronic myeloid leukemia (CML) in blast crisis (BC) remains dismal even with the availability of the BCR-ABL tyrosine kinase inhibitor imatinib, since it only offers short-term benefit in most cases. Allogeneic hematopoietic stem cell transplantation (HSCT) seems to be a viable option for BC-CML patients who attained remission. We treated ten patients with ablative allogeneic HSCT, who achieved second chronic phase (CP) by the use of imatinib after onset of BC. Median patient age was 32 years (range 17-46). Among them, four patients received HSCT from human leukocyte antigen mismatched haplo-identical family donors. After a median follow-up of 24 months (range 8-42), six out of the ten patients were alive in durable complete cytogenetic remission, one patient died in relapse 4 months after transplantation, the others died of severe acute graft-versus-host disease and associated infections. No unusual organ toxicities and engraftment difficulties were observed. Extensive chronic GVHD developed in three of six patients who could be evaluated. Patients transplanted with haplo-identical donors had a high treatment-related modality. Allogeneic HSCT may represent a feasible treatment for patients with CML in second CP attained by imatinib after onset of BC especially when a suitable donor is available.
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PMID:Allogeneic hematopoietic stem cell transplantation for patients with chronic myeloid leukemia in second chronic phase attained by imatinib after onset of blast crisis. 1828 66

Philadelphia-positive chronic myeloid leukemia (Ph+ CML) patients who are resistant to imatinib are commonly treated with second-generation tyrosine kinase inhibitors (TKIs). Limited data exist on the possible effects of these drugs on subsequent allogeneic hematopoietic stem cell transplantation (allo-HSCT).The outcome of 12 imatinib-resistant CML patients treated with dasatinib or nilotinib or both before allo-HSCT, was retrospectively analyzed. Patients were treated with second-generation TKIs for 1-17 months (median, 8). At the time of transplant, 3 patients were in complete cytogenetic response (CCgR), 3 patients in partial cytogenetic response (PCgR) and 6 patients were in less than PCgR. Donors were HLA-matched related in 4 cases and unrelated in 8 cases. Stem cell source was peripheral blood, bone marrow or cord blood in 6, 5 and 1 cases, respectively. All patients engrafted successfully and all but one achieved a full donor chimerism. Three patients experienced acute and chronic graft-versus-host disease. No cases of transplant-related mortality were recorded. Best response to allo-HSCT was complete molecular response (CMR) in 9 patients, major molecular response (MMR) in 1 patient and CCgR in 2 patients. Median follow-up was 16.5 months. At the last evaluation, 9 patients were in continuous CMR and 1 patient was in MMR; 2 patients had died of disease progression. Second-generation TKIs given before allo-HSCT do not negatively affect transplant engraftment and response rate, nor increases transplant-related toxicity.
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PMID:Second-generation tyrosine kinase inhibitors before allogeneic stem cell transplantation in patients with chronic myeloid leukemia resistant to imatinib. 1965 41

Following the introduction of tyrosine kinase inhibitors (TKIs) in chronic myelogenous leukemia (CML), allogeneic stem cell transplantation (SCT) took a shift toward high-risk patients. Considering the high relapse rates posttransplant in these selected patients, several studies evaluated posttransplant use of the TKI imatinib. Although the number of studies are still limited, and data have to be confirmed by additional studies, safety of imatinib even within the first months after SCT seems to be acceptable. Imatinib was shown to be effective in patients with molecular or hematologic relapse of chronic or accelerated phase posttransplant (CP, AP), whereas outcomes in blast phase were more unfavorable. The compound further seemed beneficial for prophylactic use in patients who achieved complete remission posttransplant. The combination of imatinib with donor lymphocytes did not result in increased toxicity or graft-versus-host disease (GVHD). First studies suggest that second-generation TKIs such as dasatinib or nilotinib are manageable posttransplant with acceptable toxicity as well. In conclusion, TKIs of the first- and second-generation are promising options for the posttransplant period of patients with CML, but algorithms for dosage, intervals from SCT, duration of application, and the combination with donor lymphocytes still have to be developed.
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PMID:Current status and perspectives of tyrosine kinase inhibitor treatment in the posttransplant period in patients with chronic myelogenous leukemia (CML). 1974 71


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