Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Improvements in the results of bone marrow transplantation for the treatment of SCID may be expected by employing purified stem-cell concentrates for patients who do not have a compatible sibling available. Refinements in the purification technique and its monitoring are required, however. For the same category of patients it seems worthwhile to continue attempts at restoration with liver cells from fetuses less than 12 weeks of age. In addition, full protection against infections should be provided for patients expected to develop GVHD, and, therefore, such patients should only be treated in centers where reverse isolation and bacteriologic decontamination can be performed. In view of the rarity of the disease, transplanters should agree on a limited number of graft protocols. For the treatment of bone marrow aplasia, attempts to identify the factors that can serve to predict the occurrence of GVHD in compatible host-donor sibling pairs should be continued. Only when the patients who will develop GVHD can be recognized in advance will it be feasible to fully exploit available GVHD reductive measures. In particular the role of the intestinal microflora should be investigated in this respect. Experimental evidence is presented, suggesting an aggravating influence of microflora on GVHD lesions, which are primarily induced by histocompatibility reactions. For such studies with incompatible siblings, the dog is the best available animal model. For the selective isolation of hemopoietic stem cells for transplantation purposes (as one means of reducing GVHD), methods for rapid identification of stem cells and immune competent cells, respectively, have to be developed. In leukemia, more research is necessary on the factors that play a role in the late complications of bone marrow transplantation. The toxicity of aggressive regimens employed in the eradication of the leukemia should be further analyzed. The collection of autologous normal hemopoietic stem cells from leukemic patients as introduced by Dicke et al. warrants further exploration to see whether these cells may replace the allogeneic transplantation procedure, thus avoiding all the complications generally encountered in GVHD. For all three diseases, it is extremely important to develop a method for the selection of compatible donors among unrelated individuals, because this will at least double the number of candidates for therapeutic bone marrow transplantation. Current progress in histocompatibility typing in the rhesus monkey and the dog makes these species excellent models for such investigations.
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PMID:Bone marrow transplantation. 1 88

Bone marrow transplantation is an experimental therapy, which has been used with success in patients with aplastic anemia, severe combined immunodeficiency and leukemia. We report here on the procedure of transplantation and the possible difficulties which can be encountered.
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PMID:[Bone marrow transplantation (author's transl)]. 32 Mar 76

A causal relation between the enzyme, adenosine deaminase (ADA), and immune dysfunction is well known: patients with congenital inactivity of ADA invariably suffer of severe combined immunodeficiency. In contrast, we found in patients treated with immunosuppressive drugs increased ADA enzyme activity. Previous findings on ADA activity in acute leukemias are until now controversial. We found normal to increased ADA activity in children with acute lymphatic leukemia (ALL) and acute myeloid leukemia (AML) in remission as long as they were treated with cytostatic drugs. In the group of cured leukemics (in continuous remission after suspension of the therapeutic regimen) the ADA activities were normal. These findings do not exclude a heterogeneity within the leukemia group. They do not explain the signs of cellular immunodeficiencies well known in patients with acute leukemias.
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PMID:[Adenosine deaminase activity in blood cells; influence of cytostatic therapy in patients with acute leukemia and with renal transplants (author's transl)]. 39 66

Rosette formation with mouse erythrocytes and other cell-surface markers were examined on lymphocytes from patients with a variety of primary immunodeficiency and lymphoproliferative disorders. Mouse erythrocyte rosette-forming cells and lymphocytes with surface immunoglobulins were regularly absent in patients with Bruton type agammaglobulinaemia, immunodeficiency and thymoma syndrome and severe combined immunodeficiency disease. However, they were present in normal or low numbers in patients with common variable immunodeficiency, selective IgA deficiency and ataxis telangiectasia. Lymphocytes from patients with acute lymphoblastic leukaemia Sezary syndrome and mycosis fungoides made no or few rosettes with mouse erythrocytes. Increased numbers of mouse erythrocyte rosette-forming cells were present in patients with chronic lymphocytic leukaemia and Waldenstrom's macroglobulinaemia. The significance of the mouse erythrocyte rosette as a B-cell marker in the analysis of primary immunodeficiency and lymphoproliferative disorders is discussed.
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PMID:Rosette formation with mouse erythrocytes. III. Studies in patients with primary immunodeficiency and lymphoproliferative disorders. 106 59

A human Philadelphia-chromosome positive chronic myeloid leukemia-blast crisis (CML-BC) cell line BV173 proliferated in the hematopoietic tissues, infiltrated various organs and caused the death of immunodeficient SCID mice. Leukemia spreading was assessed with diminished number of bone marrow cells and caused splenomegaly. The leukemic colonies grew from single cell suspension of bone marrow, spleen and peripheral blood. Bcr-abl m-RNA was detectable in bone marrow, spleen, peripheral blood, liver, lungs and brain. Dying mice demonstrated severely hypoplastic bone marrow, splenomegaly and massive metastases in the liver and kidneys. The survival time of animals was dependent on the number of inoculated leukemia cells.
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PMID:A model of Ph' positive chronic myeloid leukemia-blast crisis cell line growth in immunodeficient SCID mice. 128 28

Murine models with type C murine leukemia viruses have been used to develop major new prophylactic and therapeutic strategies in vaccination, drug therapy of acute virus exposure and chronic viremia, combination therapy, prevention of maternal transmission, and therapy targeted to the central nervous system. Transgenic mice expressing either the whole human immunodeficiency virus type 1 (HIV-1) provirus or subgenomic sequences allow the in vivo analysis of selected HIV-1 functions. The full replicative cycle of HIV-1 can be studied in human/mouse chimerae which were created by transplanting human hematolymphoid cells into SCID mice. The chimeric SCID mouse models have been used successfully to evaluate anti-HIV-1 drugs. The role of the various murine retrovirus systems in the development of anti-HIV-1 and anti-AIDS therapies is summarized.
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PMID:Development of antiviral treatment strategies in murine models. 132 85

2-Chlorodeoxyadenosine (CdA) is active in chronic lymphocytic leukemia, hairy-cell leukemia, and low-grade lymphomas. In part, this spectrum of activity may be attributable to the selective toxicity of CdA to nondividing lymphocytes and monocytes. However, CdA is unstable at acidic pH and is degraded by bacterial nucleoside phosphorylases. The present experiments demonstrate that the 2'-arabino-fluoro derivative of CdA, designated CAFdA, is also directly toxic to quiescent lymphocytes and macrophages. Unlike CdA, CAFdA was stable at pH 2 and resisted degradation by Escherichia coli nucleoside phosphorylase. Cell killing was preceded by the formation of DNA strand breaks and could be prevented by supplementation of the medium with deoxycytidine. The initial DNA damage initiated the pattern of oligonucleosomal DNA fragmentation characteristic of apoptosis. Mutant lymphoblasts, deficient in deoxycytidine kinase, with elevated cytoplasmic 5'-nucleotidase, or with expanded deoxynucleotide pools secondary to increased ribonucleotide reductase activity, were cross-resistant to both CAFdA and CdA toxicity. One-week oral treatment with CAFdA (1 mg/ml in drinking water) achieved an average plasma concentration of 0.56 microM and eliminated 90% of chronic lymphocytic leukemia cells transplanted into severe combined immunodeficiency (scid) mice. Under the same conditions, CdA was much less active. Collectively, these results suggest that CAFdA could be effective as an oral agent in indolent lymphoproliferative diseases and in autoimmune diseases where lymphocyte and monocyte depletion is desirable.
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PMID:Oral antilymphocyte activity and induction of apoptosis by 2-chloro-2'-arabino-fluoro-2'-deoxyadenosine. 134 62

Human acute leukemia, with a chromosomal translocation involving chromosomes 4 and 11, t(4;11)(q21;q23), is the most common form of leukemia in infants and responds very poorly to conventional therapy. A human CD19+ mixed-lineage leukemia cell line with a t(4;11)(q21;q23) translocation, RS4;11, disseminated and proliferated in the hematopoietic tissues and other organs of mice with severe combined immunodeficiency in a manner similar to that observed in humans and killed 100% of the animals. The anti-CD19(B43)-pokeweed antiviral protein immunotoxin selectively inhibited clonogenic RS4;11 cells in vitro, markedly reduced the burden of disseminated leukemia of severe combined immunodeficient mice, and, most importantly, resulted in the long-term survival of treated animals. This severe combined immunodeficient mouse model should be useful for the design of more effective treatment strategies for refractory human leukemias.
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PMID:Establishment of a human t(4;11) leukemia in severe combined immunodeficient mice and successful treatment using anti-CD19 (B43)-pokeweed antiviral protein immunotoxin. 137 Feb 13

The study of new therapeutic approaches for refractory human leukemia has been hampered by the lack of relevant in vivo models with disseminated disease, particularly T acute lymphoblastic leukemia (T-ALL). In the present study we evaluated methods for establishing and therapy of a human T-ALL cell line (MT-ALL) in 73 SCID mice. MT-ALL is a T-cell receptor alpha/beta +, CD3+, and CD7+ leukemia cell line, derived from a patient with refractory disease and early death. Injection of 5 x 10(7) MT-ALL cells i.v. caused disseminated human leukemia in hematopoietic and nonhematopoietic organs in 100% of SCID mice (n = 9) leading to death or terminal disease at 65 to 70 days after a uniform clinical course. To study possible therapeutic approaches for disseminated leukemia we utilized an immunotoxin, DA7, constructed by chemically linking the mouse IgG2b anti-CD7(3A1E) monoclonal antibody which recognizes a pan-T-cell marker expressed on almost all T-cell leukemias to deglycosylated ricin A-chain, a catalytic plant toxin and inhibitor of protein synthesis. Administration of DA7 led to greater than 5 log kill of clonogenic MT-ALL cells in vitro and selectively inhibited protein synthesis. DA7 was administered to mice at a dose of 10 micrograms/mouse/day for 5 consecutive days starting 8 days after i.v. inoculation of leukemia. The immunotoxin therapy resulted in significant long term survival over 348 days compared to untreated or control mice treated with anti-CD7 antibody and deglycosylated ricin A-chain which were all dead by day 70 (P less than 0.001). Even after more than 11 months there was no evidence of disease in 82% of the DA7 treated animals. SCID mice given i.p. injections (n = 9) developed an i.p. tumor mass but demonstrated metastasis outside the peritoneum with disseminated leukemia in hematopoietic and nonhematopoietic organs, a finding different from most conventional nude mouse models. The leukemia was fatal in 100% and killed the animals at 68-95 days. SCID mice given i.p. injections of MT-ALL completely responded to therapy with DA7, resulting in survival of 100% of the animals (n = 10) at 216 days (P less than 0.001 compared to untreated animals). Anti-CD7 antibody, deglycosylated ricin A-chain, and a control anti-melanoma immunotoxin (IND1-RTA) showed no therapeutic effect. We conclude that DA7 is an effective in vivo therapeutic agent against human MT-ALL in the SCID mouse system, suggesting potential usefulness for therapy of humans with poor prognosis T-cell leukemia.
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PMID:Successful treatment of human acute T-cell leukemia in SCID mice using the anti-CD7-deglycosylated ricin A-chain immunotoxin DA7. 137 Oct 92

Homozygosity for the severe combined immunodeficiency (scid) mutation results in a block in T- and B-lymphocyte development. An unusually high incidence of spontaneous thymic lymphoma development was observed after transfer of this mutation from the C.B-17 congenic strain background onto the diabetes-susceptible nonobese diabetic (NOD) background. Thymomagenesis in the NOD-scid/scid mouse was associated with expression of an NOD mouse-unique endogenous ecotropic murine leukemia provirus locus (Emv-30, mapped to proximal region of chromosome 11) not expressed in the standard substrain NOD/Lt thymus. All tumors exhibited insertions of ecotropic proviruses, whereas only a subset also exhibited proviral integrations of mink cell focus-forming retrovirus. Neither class of retrovirus was associated with consistent integration into genes previously associated with activation of oncogenesis. We propose that the unusual features of T-cell ontogeny characteristic of the NOD inbred strain synergize with the scid-imparted block in thymocyte development, leading to activation of the NOD-unique Emv-30 to initiate thymomagenesis.
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PMID:The nonobese diabetic scid mouse: model for spontaneous thymomagenesis associated with immunodeficiency. 137 93


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