Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A combined retrospective and prospective study of 129 beta-thalassaemia major patients seen between 1965 and 1995 in Sabah Hospital, Kuwait has been carried out. The age range at diagnosis was 2 to 84 months, median 9 months. In approximately 80 per cent, the patients were outcomes of first- or second-cousin marriages. Nine (7 per cent) of the patients were HBsAg positive, while 42 (33 per cent) were hepatitis C seropositive. Eleven (9 per cent) patients had had bone marrow transplantation (BMT). There was no BMT-related mortality, but there were three graft rejections and two cases of chronic graft-versus-host disease (GVHD).
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PMID:beta-Thalassaemia major in Kuwait. 981 98

Immunological recognition of foreign cells is a primary concern in both transfusion and transplantation medicine. Our unique approach to this problem is to globally camouflage the surface of the foreign cell using nonimmunogenic, long chain polymers such as methoxypoly(ethylene glycol) [mPEG]. mPEG-modification of red blood cells effectively attenuates both antibody binding to surface epitopes and decreases the inherent immunogenicity of foreign, even xenogeneic red cells. These cells exhibit normal structural and functional characteristicsin vitro and exhibit normal in vivo survival in animal models. Pegylation of white blood cells (particularly antigen presenting cells and T lymphocytes) surprisingly prevents recognition of foreign class II molecules and prevents T cell proliferation in response to foreign MHC molecules. Potential applications for the covalent binding of nonimmunogenic, long chain polymers (e.g., PEG) to intact cells include, but are not limited to: 1) derivatized RBC to diminish transfusion reactions arising from sensitization to minor blood group antigens (allosensitization) in the chronically transfused (e.g., sickle and thalassemia patients); 2) use of mPEG modification of "passenger" lymphocytes to prevent immune recognition and graft versus host disease; and 3) derivatization of the vascular endothelium of donor tissues prior to transplantation to prevent/diminish acute tissue rejection. In contrast to highly specific blocking mechanisms (e.g., anti-CD4; proteolytic removal of RBC A/B antigens), the generation of globally camouflaged (i.e., stealth) cells may more effectively prevent the often complex and redundant events leading to immune recognition of foreign cells.
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PMID:Cellular camouflage: fooling the immune system with polymers. 1019 54

Thirty-two thalassemic patients with a median age of 7.7 years (range 3.4-26 years) were given a second HLA-identical related marrow transplant (BMT2) for graft failure. Four patients were in class 1 and 28 patients in classes 2 and 3. Twenty-one patients had full thalassemia recurrence (first group) and 11 patients had aplastic marrows (second group) either with or without residual donor marrow cells after the first BMT (BMT1). As conditioning regimen for BMT2 all but five patients received BUCY or CY in association with total lymphoid irradiation (TLI) and/or anti-lymphocyte globulin (ALG), whereas nine patients received a new preparative regimen with hydroxyurea, azathioprine, fludarabine before conditioning with BUCY. Twenty one of 31 evaluable patients (67.7%) had initial, and 16 (51.6%) had sustained engraftment. Ten patients (32.3%) failed to engraft. Overall and event-free survival for the entire group of patients were 49% and 33%, respectively, with a median follow-up of 4 years (range 0.6-14 years) for surviving patients. Event-free survival was higher in the second group of patients compared with the first group (41% vs 29%). The second group of patients appeared to have less graft failure compared with the first group (30% vs 63%; P = 0.1). Transplant-related mortality was 28%. A linear stepwise regression analysis revealed that occurrence of graft failure within 60 days after BMT1 (P = 0.04) and absence of residual donor marrow cells (P = 0.009) predicted for graft failure following BMT2, whereas the occurrence of graft failure after 60 days (P = 0.03) had a positive influence on survival following BMT2. The incidence of grade >/=2 acute GVHD was low (14%). Eight of nine patients who received the new preparative regimen are alive, four without thalassemia. This study shows that BMT2 can be an effective therapy for a proportion of patients with poor survival expectancies despite conventional treatment.
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PMID:Second marrow transplants for graft failure in patients with thalassemia. 1062 38

Over the past decade, safety of blood has increased tremendously because of better donor screening as well as testing of the units for transmissible diseases. Component therapy has allowed more effective and economic use of blood. Whole blood is rarely used; instead, packed red cells, platelets, and fresh frozen plasma (FFP) are the most common components used. These products are further refined using irradiation and microaggregate filters and in the case of FFP, viral inactivation. Irradiation prevents transfusion-associated graft versus host disease, whereas microaggregate filters remove leukocytes, decreasing the rates of alloimmunization, febrile nonhemolytic (FNH) reactions, and cytomegalovirus (CMV) transmission. Autologous donation in older children probably provides the safest blood as far as transmissible diseases are concerned. More families request a directed donation and solicit physician help in deciding as well as making arrangements for autologous and/or directed donations. Transfusions of blood and blood components in children are often challenging and require a knowledge of physiologic changes in hemoglobin and blood volumes during different ages. The unique needs of neonates, immunocompromised patients, and patients with congenital hemolytic anemia (sickle cell, thalassemia) mandate that the pediatrician have an appropriate knowledge of transfusion volumes and choice of blood product as well as indications for transfusion.
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PMID:Pediatric transfusion therapy: practical considerations. 1079 77

Twenty-nine patients with thalassemia and a median age of 6 years (range 1.1-33 years) were given a BMT from an alternative donor. Six of the 29 donors were HLA-phenotypically identical and two were mismatched relatives, 13 were mismatched siblings and eight were mismatched parents. Six patients received no antigen (relatives), 15 patients one antigen, five patients two antigen and three patients three antigen disparate grafts. Twenty-three patients were in class 2 or class 3, whereas six patients were in class 1. Thirteen patients were given BUCY, nine patients BUCY plus ALG, six patients BUCY plus TBI or TLI and one patient BUCY with prior cytoreductive-immunosuppressive treatment as conditioning. As GVHD prophylaxis four patients received MTX, 22 CsA + MTX + methylprednisolone (MP) and three patients CsA + MP. Thirteen of 29 patients (44.8%) had sustained engraftment. The probability of graft failure or rejection was 55%. There were no significant differences between antigen disparities and graft failure. The incidence of grade II-IV acute GVHD was 47.3% and chronic GVHD was 37.5%. The incidence of acute GVHD was higher in patients receiving one or two antigen disparate in the GVHD direction grafts (vs no antigen) (P EQ 0.04; odds ratio 10.8; 95% CI 1.5-115). The probability of overall and event-free survival was 65% and 21%, respectively, with median follow-up of 7.5 years (range 0.6-17 years) for surviving patients. The degree of HLA disparity between patient and donor did not have a significant effect on survival. The incidence of nonhematologic toxicity was low. Transplant-related mortality was 34%. GVHD (acute or chronic) was a major contributing cause of death (50%) followed by infections (30%). We conclude that at present, due to high graft failure and GVHD rates, BMT from alternative donors should be restricted to patients who have poor life expectancies because they cannot receive adequate conventional treatment or because of alloimmunization to minor blood antigens.
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PMID:Bone marrow transplantation from alternative donors for thalassemia: HLA-phenotypically identical relative and HLA-nonidentical sibling or parent transplants. 1080 1

The potential advantage of in utero HSC transplantation over a postnatal BMT is that early curative therapy could be given to an affected fetus, thus eliminating standard intensive immunosuppressive, marrow-ablative conditioning. It is apparent from studies in animals and humans that MHC-mismatched donor HSC of either fetal or adult origin can engraft in fetal recipients if the transplants are done sufficiently early in gestation. However, except for SCID, the percentage of donor pluripotent HSC that engraft is unacceptably low. We had hoped that for diseases such as thalassemia there would be a selective survival advantage for committed donor progenitor cells resulting in a high percentage of donor cell engraftment. At least based upon the experience in human fetuses with alpha- or beta-thalassemia, this has not been the case. Furthermore, for the majority of potential recipients of in utero HSC transplants, the marrow is non-defective, and the small percentage of pluripotent donor HSC that engraft would not be expected to selectively expand post-transplant. Our own results suggest that the non-defective fetal mouse and rhesus monkey are excellent models in which to study both stem cell engraftment, rejection, and tolerance induction. In our studies in non-defective mice with normal hematopoiesis, while the percentage of donor cells that are present is quite low, in only a small number of these animals were we able to induce permanent skin graft tolerance. Thus, while we found microchimerism in approximately 75% of recipients, less than 10% became tolerant. Even when we co-injected a large number of DC precursors, similar to what has been shown to induce tolerance to allogeneic liver, most of the animals failed to become tolerant to donor skin grafts. Interestingly, donor c-kit+ cells can be recruited with cytokines into the peripheral blood in engrafted mice, although these cells do not seem to be sufficient to induce tolerance to donor skin grafts, suggesting that the type (and location) of the engrafted donor cell plays a key role in tolerance induction. Our results in the fetal monkey model parallel those in the mouse, i.e., only a small number of donor cells engraft with limited tolerance induction. Interestingly, we found in our study of DC that GVHD was induced in those murine recipients of both allogeneic marrow and DC. It is likely that there were a sufficient number of mature DC in the preparation to facilitate a donor cytotoxic response towards the host. As a consequence there was also a significant increase in the percentage of donor cells that engrafted in the survivors. Future studies will focus on ways of blocking the graft vs host reaction while still maintaining the graft-promoting role of the donor T cell.
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PMID:Tolerance induction post in utero stem cell transplantation. 1110 59

We have previously shown that the keys to high-level nontoxic chimerism in syngeneic models are stem cell toxic, nonmyelotoxic host treatment as provided by 100-cGy whole-body irradiation and relatively high levels of marrow stem cells. This approach was unsuccessful in H-2 mismatched B6.SJL to BALB/c marrow transplants, but with tolerization, stable multilineage chimerism was obtained. Ten million B6.SJL spleen cells were infused intravenously into BALB/c hosts on day -10 and (MR-1) anti-CD40 ligand monoclonal antibody (mAb) injected intraperitoneally at varying levels on days -10, -7, -3, 0, and +3 and the BALB/c mice irradiated (100 cGy) and infused with 40 million B6.SJL/H-2 mismatched marrow cells on day 0. Stable multilineage chimerism at levels between 30% to 40% was achieved in the great majority of mice at 1.6 mg anti-CD40 ligand mAb per injection out to 64 weeks after transplantation, without graft-versus-host disease. The transplanted mice were also tolerant of donor B6.SJL, but not third-party CBA/J skin grafts at 8 to 9 and 39 to 43 weeks after marrow transplantation. These data provide a unique model for obtaining stable partial chimerism in H-2 mismatched mice, which can be applied to various clinical diseases of man such as sickle cell anemia, thalassemia, and autoimmune disorders.
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PMID:Allogeneic chimerism with low-dose irradiation, antigen presensitization, and costimulator blockade in H-2 mismatched mice. 1115 37

Type II congenital dyserythropoietic anaemia (CDA-II or HEMPAS) is an autosomal recessive disorder, representing the most frequent form of congenital dyserythropoiesis. It is characterised by normocytic anaemia, variable jaundice and hepato-splenomegaly. Gallbladder disease and secondary haemochromatosis are frequent complications. We report a case characterised by severe transfusion-dependent anaemia. The proband inherited CDA-II in association with beta-thalassaemia trait. Splenectomy did not abolish the transfusion dependence and this, in association with poor compliance to iron-chelation therapy, prompted us to consider bone marrow transplantation (BMT) from his HLA-identical sibling. The preparative regimen included busulfan, thiotepa and fludarabine, and graft-versus-host disease prophylaxis consisted of cyclosporin A and short-term methotrexate. Engraftment of donor cells was prompt and the post-transplant course uncomplicated. The patient is alive and transfusion-independent 36 months after allograft. This is the first case of severe CDA-II to undergo BMT. Analysis of this pedigree suggests that interaction with beta-thalassaemia enhanced the clinical severity of CDA-II, making BMT an attractive therapy for patients with transfusion dependence.
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PMID:Bone marrow transplantation in a case of severe, type II congenital dyserythropoietic anaemia (CDA II). 1128 93

Bone marrow transplantation (BMT) has the potential to treat hemoglobinopathies (sickle cell and thalassemia) autoimmunity (diabetes, lupus, multiple sclerosis, rheumatoid arthritis, Crohn's colitis) and enzyme deficiency states. Graft versus host disease (GVHD) is a major complication and limitation to the therapeutic application of BMT. There have been many clinical trials and experimental animal models that have attempted to control GVHD through the engineering of the donor bone marrow cells (BMC). Historically, several methods have demonstrated effectiveness in controlling GVHD; however they were also associated with a marked increase in the rate of graft failure. Highly purified hematopoietic stem cells (HSC) engraft quite readily in genetically-matched recipients while they do not engraft as easily in MHC-disparate recipients. The numbers of HSC must be increased 100-200 fold in order to overcome the allogeneic barrier. We were the first to phenotypically and to functionally characterize a novel cell in the bone marrow that enables engraftment of highly purified HSC in allogeneic recipients. The discovery of graft facilitating cell populations has resulted in the restoration of the engraftment-potential of purified HSC between genetically-disparate individuals. The addition of facilitating cells (FC) to T cell-depleted BMC grafts results in allogeneic engraftment without GVHD or graft failure. New strategies of BMC engineering that retain FC and HSC but avoid GVHD have allowed successful engraftment in mismatched and older recipients. These techniques have expanded the therapeutic potential of BMT to virtually every candidate as well as to non-malignant diseases in which the morbidity associated with conventional BMT could not be accepted. This article reviews the transition of the FC technology from bench to bedside and discuss the potentially broad-reaching applications of BMT and mixed chimerism.
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PMID:Bone marrow cell graft engineering: from bench to bedside. 1134 54

Mixed hemopoietic chimerism has the potential to correct genetic hemological diseases (sickle cell anemia, thalassemia) and eliminate chronic immunosuppressive therapy following organ transplantation. To date, most strategies require either recipient conditioning (gamma-irradiation, depletion of the peripheral immune system) or administration of "mega" doses of bone marrow to facilitate reliable engraftment. Although encouraging, many issues remain that may restrict or prevent clinical application of such strategies. We describe an alternative, nonirradiation based strategy using a single dose of busulfan, costimulation blockade, and T cell-depleted donor bone marrow, which promotes titratable macrochimerism and a reshaping of the T cell repertoire. Chimeras exhibit robust donor-specific tolerance, evidenced by acceptance of fully allogeneic skin grafts and failure to generate donor-specific proliferative responses in an in vivo graft-versus-host disease model of alloreactivity. In this model, donor cell infusion and costimulation blockade without busulfan were insufficient for tolerance induction as donor-specific IFN-gamma-producing T cells re-emerged and skin grafts were rejected at approximately 100 days. When applied to a murine beta-thalassemia model, this approach allows for the normalization of hemologic parameters and replacement of the diseased red cell compartment. Such a protocol may allow for clinical application of mixed chimerism strategies in patients with end-stage organ disease or hemoglobinopathies.
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PMID:Costimulation blockade, busulfan, and bone marrow promote titratable macrochimerism, induce transplantation tolerance, and correct genetic hemoglobinopathies with minimal myelosuppression. 1144 Nov 22


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