Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002874 (aplastic anemia)
 5,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Of 14 patients who underwent allogeneic or syngeneic bone marrow transplantation, 6 had a transient appearance of small blastoid cells in the bone marrow after transplantation. Most of these patients (11) had leukemia, although 3 had severe aplastic anemia. The cells were 8-18 micron in diameter and had scant cytoplasm and dense nuclei with smooth, homogeneous chromatin. They often had distinct nuclear clefts. These cells constituted 4.0-21.3% of the total number of bone marrow cells. They were not reactive with peroxidase, alpha-naphtyl butylate esterase, naphthol AS-D chloroacetate esterase, or periodic acid-Schiff stains. Immunocytochemical analysis revealed that the small blastoid cells expressed terminal deoxynucleotidyl transferase, Ia-like, CD19, and CD10 antigens and cytoplasmic mu heavy chains, indicating a precursor B-cell phenotype. CD20 antigen was not expressed on these cells. The data suggest that cytoplasmic mu may be expressed earlier than CD20 antigen in the differentiation of B-cell lineage. The morphologic, cytochemical, and immunophenotypic characteristics did not distinguish these nonneoplastic cells distinctly from leukemic lymphoblastic cells. The increase of small blastoid cells was a transient and self-limited phenomenon, in contrast to that of neoplastic blasts. These cells should be recognized as a common component of the bone marrow of marrow transplant recipients. The significance and role of these cells in immune recovery and hematopoiesis remain uncertain.
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PMID:The transient appearance of small blastoid cells in the marrow after bone marrow transplantation. 161 19

In order to investigate the involvement of apoptosis in the pathogenesis of aplastic anaemia (AA) we measured the expression of the Fas receptor (membrane protein that triggers apoptosis), Fas ligand (FasL), bcl-2 (cytoplasmatic protein that blocks apoptosis) and p53 (nuclear protein that induces apoptosis) in CD3 and CD19 lymphocytes from the peripheral blood or bone marrow of controls, patients with AA, aplastic anaemia in complete remission (AA-CR) and multiply transfused patients without aplastic anaemia. The Fas receptor was overexpressed in both T and B lymphocytes from the peripheral blood and bone marrow from patients with AA. These abnormalities were not detected in AA-CR or multiply transfused patients. CD3/FasL cells were not increased and no FasL expression was detected in B lymphocytes. Bcl-2 was highly expressed in lymphocytes from controls, AA, AA-CR and multiply transfused patients (> 99% of positive cells) whereas p53 was not detected in any group. To further characterize the functional activity of the Fas receptor we performed a Fas-induced apoptosis assay in peripheral blood lymphocytes using an anti-Fas monoclonal antibody. The crosslinking of the Fas receptor transduced an increased apoptotic signal in lymphocytes from AA patients, but not in lymphocytes from controls, AA-CR patients or multiply transfused patients. Taken together, these data suggest that a Fas-based mediated apoptosis without the apparent participation of bcl-2 or p53 is a possible mechanism of lymphocyte depletion in patients with AA. In addition, these findings suggest that Fas expression is a continuous event occurring from progenitor bone marrow cells to mature cells.
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PMID:Fas-mediated apoptosis with normal expression of bcl-2 and p53 in lymphocytes from aplastic anaemia. 958 Feb 7

Refractory anemia (RA) in myelodysplastic syndrome (MDS) without prominent dysplasia closely resemble the mild type of aplastic anemia (AA) in their hematological features. This sometimes makes it difficult to distinguish clearly between the two diseases. Using the multi-color flow cytometric technique, we compared cell surface antigen expression patterns on bone marrow hematopoietic progenitor cells which were isolated as a CD34 positive- CD45 dull positive with low side scatter intensity (CD34(+)CD45(dull+)SSC(low)) population in flow cytogram between RA (n=12) and AA (n=11). The antigens analyzed in CD34(+)CD45(dull+)SSC(low) mononuclear cells were: CD38 and CD71 for cell growth-related antigens, CD 33 and CD13 for myeloid and monocytoid lineage-associated antigens, CD7 and CD19 for lymphoid lineage, and CD14 for a monocytic lineage specific antigen. The percentages of CD34(+)CD45(dull+)SSC(low) cells in bone marrow non-erythroid mononuclear cells, and the expression frequencies of CD38, CD71, CD33 and CD13 antigens in CD34(+)CD45(dull+)SSC(low) progenitors were all significantly decreased in AA compared to normal bone marrows (n=7) (P<0.005). In contrast, in RA bone marrows the percentages of CD34(+)CD45(dull+)SSC(low) cells showed wide distribution and the cell surface antigen expression patterns varied among each case: some cases showed low frequencies of CD38 and CD71 expression as well as AA, whereas the others showed high expression frequency of specific antigen(s) which may reflect the clonal expansion of an abnormal clone in bone marrow. An MDS patient who had progressed from RA to RAEB showed further projecting pattern of expression of CD38 and CD33 in CD34(+)CD45(dull+)SSC(low) population in accordance with the disease progression. These data suggest that analysis of cell surface antigen expression patterns of CD34(+)CD45(dull+)SSC(low) progenitor cells by multi-color flow cytometry appears to be a useful method for qualitative and quantitative assessment of marrow progenitor states in AA and RA, therefore this method could be helpful for early detection of clonal evolution in MDS.
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PMID:Comparative multi-color flow cytometric analysis of cell surface antigens in bone marrow hematopoietic progenitors between refractory anemia and aplastic anemia. 1086 34

Fifty three patients (pts) received an allogeneic hematopoietic transplant using peripheral blood progenitor cells (PBPC). Diagnosis were acute myeloid leukemia (AML) in 16 pts, acute lymphoblastic leukemia (ALL) in 15, chronic myeloid leukemia (CML) in first chronic phase in 12, aplastic anemia in 4, myelodysplasia in 3 and Hodgkin's disease, major thalasemia and Hunter's syndrome in one each. Mean age was 20 years-old (2-55), 28 males and 25 females. Conditioning regimens were total body irradiation with 1200 cGy and cyclophosphamide 120 mg/kg in 38 pts, busulfan 16 mg/kg and cyclophosphamide 120 mg/kg in 10 pts, total lymphoid irradiation and cyclophosphamide in 3, 2 pts received other chemotherapy based conditionings. PBPC were infused unmanipulated through a central catheter. Graft versus host disease (GVHD) prophylaxis was cyclosporin and short course methotrexate. Donors were 6/6 HLA compatible siblings in 52 cases and 5/6 match in one case. PBPC mobilization was done with G-CSF at a dose of 10 micrograms/kg/day subcutaneously for four days, pheresis started on day 5. Bone marrow harvest was also done in the first thirty cases. Mean cellularities for CD34, CD3, CD4, CD8, CD56, CD19 (cel x 10(6)/kg) were 4.12; 4.59; 2.57; 1.9; 0.55 and 0.68, respectively. Mean recovery of neutrophils > 500/microL was obtained on day +11 and platelets > 20,000/microL on day +13. Patients were hospitalized for a mean period of 26 days (range 18-39) and days with parenteral antibiotics were 12.2 (5-45). Two pts had venoocclusive disease of the liver. Transplant related mortality was 15%. Acute graft versus host disease (GVHD) was observed in 43.4% of pts, only 5 pts had acute GVHD III or IV. Mean time for aGVHD diagnosis was +23 (8-76). Forty three pts were evaluable for chronic GVHD with a mean follow-up of 18 months (4-39). Chronic GVHD was observed in 26.4% by day +240, only 2 pts developed severe cGVHD. The present experience demonstrates an acceptable incidence for cGVHD; however, taking into account recent reports showing an increase of this complication, it seems reasonable not to perform this procedure for non-malignant diseases in which graft versus malignancy effect is not to be expected.
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PMID:[Allogeneic hematopoietic transplantation with stem cells extracted from peripheral blood]. 1096 6

The hydroquinone and catechol like metabolites, NCQ344 and NCQ436 respectively, of the antipsychotic remoxipride have recently been demonstrated to induce apoptosis in myeloperoxidase (MPO)-rich human bone marrow progenitor and HL-60 cells [S.M. McGuinness, R. Johansson, J. Lundstrom, D. Ross, Induction of apoptosis by remoxipride metabolites in HL-60 and CD34+/CD19- human bone marrow progenitor cells: potential relevance to remoxipride-induced aplastic anemia, Chem. Biol. Interact. 121 (1999) 253-265]. In the present study, we determined the molecular mechanisms of apoptosis induced by these remoxipride metabolites in HL-60 cells. Our results show that apoptosis was accompanied by phosphatidylserine (PS) exposure, activation of caspases-9, -3, -7 and DNA cleavage. In HL-60 cells treated with the hydroquinone NCQ344 and catechol NCQ436, the general caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp. fluoromethyl ketone (Z-VAD.FMK) blocked DNA cleavage and activation of caspases-9, -3/-7. In addition, PS exposure was significantly but not completely inhibited by Z-VAD.FMK. These results demonstrate that although Z-VAD.FMK inhibitable caspases are necessary for maximal apoptosis induced by NCQ344 and NCQ436, additional caspase-independent processes may orchestrate changes leading to PS exposure during apoptosis induced by the remoxipride polyphenolic metabolites.
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PMID:Caspase-dependent and -independent mechanisms in apoptosis induced by hydroquinone and catechol metabolites of remoxipride in HL-60 cells. 1099

Antilymphocyte globulins (ALG) are immunosuppressive agents of animal origin currently used in clinical transplantation medicine and for the treatment of severe aplastic anemia. The potency of each batch is tested in vivo using primates as hosts for allogeneic skin transplantation. The test is done with a maximum of three animals, one as a control and two after the treatment with ALG. The two in vitro methods in use are a cytotoxic assay and the rosette inhibition assay. These methods are evaluated with the microscope. Besides wellfare aspects these methods require a lot of experience, are subjective, difficult to validate and the information about the biological potency of the sera is questionable. The aim of our study is a better biological characterisation as a prerequisite to subsequently define an in vitro alternative for the potency test in monkeys. Using a competition assay with monoclonal antibodies we can identify several specificities directed against functional molecules on T cells (e.g., CD2, CD3, CD5, CD28), B Cells (CD19), macrophages and natural killer cells (CD16) and nonlineage specificities such as CD18, CD25, CD29, CD95. This method could describe a part of the biological potency and control homogeneity of batches. The cytotoxic capacity of ALG either with or without complement as well as DNA-fragmentation characteristic for apoptosis can be analysed by flowcytometry using propidiumiodide- (PI) incorporation. Immunoprecipitation of cell-lysate with ALG<<s and subsequent incubation with radioactive ATP (kinase-assay) shows specific bands which seem to be identical between different batches of one product.
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PMID:[Potency testing of anti-lymphocyte Globulins: In vitro alternatives for the monkey skin-graft assay] 1117 34

Graft failure is a life-threatening complication after transplantation of hematopoietic stem cells. We report a cohort of 11 pediatric patients with leukemias (n=8) and severe aplastic anemia (n=3) who experienced graft rejection after myeloablative transplantation from mismatched related donors (n=6) or after cord blood or matched unrelated donor transplantation (n=5). In the latter, the original donor was not available anymore. All patients were re-transplanted with CD34(+) selected or CD3/CD19 depleted stem cells from a second, haploidentical donor. Median time span from diagnosis of rejection to second transplant was 9 days. Reconditioning regimens comprised total lymphoid irradiation, thiotepa, fludarabine, ATG/OKT3 and were well tolerated. A median number of 23.5x10(6)/kg stem cells with 95,000/kg residual T-cells were infused. Sustained engraftment of neutrophiles/platelets and complete donor chimerism was achieved in all patients (ANC>500/microl: 9 (11-32) days). No GvHD>grade II was observed. 8/11 patients are disease free (median follow up 1.9 years; 1 year-EFS=72%). Causes of death were: pneumonitis, infection, relapse. Thus, haploidentical transplantation represents a realistic option to rescue patients with graft failure within a short time span, for whom a second donation from the original donor is not available. The use of different donors may contribute to avoid a second rejection.
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PMID:Retransplantation with stem cells from mismatched related donors after graft rejection in pediatric patients. 1788 40

This study was aimed to investigate the characteristics of lymphocyte immune abnormality in children idiopathic aplastic anemia (IAA) in order to explore the immune pathogenesis of childhood IAA. The phenotypes of lymphocytes, the ratios of Th1/Th2 and Tc1/Tc2, the levels of CD25(+) and CD4(+)CD25(+) T lymphocytes in peripheral blood of IAA patients were measured at the onset of disease by flow cytometry and were compared with that in normal controls. The influences of those immunological indicators on prognosis of IAA were also analyzed. The results showed that there were 40 cases of severe aplastic anemia (SAA) and 12 cases of mild aplastic anemia (MAA). The levels of CD3(+) CD8(+) T cells in SAA group and MAA group were significantly higher than those in controls (p < 0.05). The levels of CD3(+) and CD3(+) CD4(+) T cells in MAA group were lower than that in SAA group (p < 0.05), but there were no difference was compared with control group. No differences of the levels of CD3(-)CD19(+) T cells were between the both SAA and MAA groups and the control group. The levels of CD3(-)CD56(+) T cells in SAA group and MAA groups were lower significantly than that in control group. As compared to control group, the levels of Th1 and Tc1 in SAA group and MAA groups increased significantly (p < 0.05), and the ratios of Th1/Th2 and Tc1/Tc2 in SAA group and MAA groups increased significantly (p < 0.05). The level of Th2 increased in SAA group. As compared to MAA group, the levels of Th1 and Tc1 and the ratios of Th1/Th2 and Tc1/Tc2 in SAA group increased significantly (p < 0.05). The levels of CD25(+) T lymphocyte in SAA group and MAA group increased significantly (p < 0.05), and were higher than that in normal controls, but levels of CD4(+)CD25(+) T lymphocyte and ratio of CD4(+)CD25(+)/CD4(+) in SAA group and MAA group had no significant difference. It is concluded that the abnormal lymphocyte immune function exist in the onset of childhood IAA. The polarization of Th1/Th2 and Tc1/Tc2 shifts to Th1 and Tc1 cells. These changes closely relate to severity of the disease. There is high level of CD25(+) T lymphocyte in children IAA. These changes reveal that abnormality of immune function plays an important role at the onset of childhood idiopathic aplastic anemia.
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PMID:[Analysis of lymphocyte immune abnormality in 52 cases of children idiopathic aplastic anemia]. 1892 2

The outcome of haematopoietic SCT (HSCT) from matched unrelated donors in children with severe aplastic anaemia (SAA) has improved significantly in the last decade and should be offered to all children who fail to respond to their first course of combined immunosuppressive therapy. High-resolution typing for HLA class I and II is mandatory for donor selection. In 10/10 or 9/10 alleles matched donors, a non-TBI conditioning based on fludarabine, CY and anti-thymocyte globulin is sufficient to allow for sustained engraftment when unmanipulated BM is used. Owing to increased rates of cGVHD after PBSC transplantation are reported in young patients, BM is the preferred stem cell source. HSCT from mismatched related and unrelated donors are still high-risk procedures. New techniques for graft manipulation such as CD3/CD19 depletion might improve engraftment and immune reconstitution. In T-cell depleted grafts, irradiation-based conditioning seems to be inevitable to reduce the high risk for rejection.
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PMID:Risk-adapted procedures for HSCT from alternative donor in children with severe aplastic anaemia. 1897 55

This study was purposed to explore the diagnostic role of flow cytometry in immunorelated pancytopenia (IRP). After 50 IRP patients were hospitalized, the concentration of serum ferritin, folic acid and vitamin B(12), immunologic test, platelet antibody, test of hepatitis A, B and C, haemolysis test and bone marrow smear examination were carried out, meanwhile the chromosome karyotype analysis and some routine examinations were performed. The 50 patients were divided into group A and group B. Group A consisted of 22 patients who were undefinedly diagnosed and intended to diagnosed as IRP, group B consisted of 28 definedly diagnosed patients with hematologic malignancies, including 7 cases of aplastic anemia, 2 of paroxysmal nocturnal hemoglobinuria, 10 of myelodysplastic syndrome, 9 of megaloblastic anemia. In addition, 30 normal people were used as normal control group (group C). For groups A and B, the binding autoantibodies of bone marrow stem/progenitor cells, erythroblasts and myelocytes were detected by flow cytometry, meantime the ratio of total B-(CD10(+)) and CD5(+) B-lymphocytes in peripheral blood was assayed. For control group, the ratios of CD19(+) and CD5(+) B lymphocytes in peripheral blood were determined alone. The results indicated that the detection of bone marrow autoantibodies in 20 patients of group A showed positive with 90.90%. The IgG type was found mostly in antibody binding types, next the IgM type, the IgA type was fewer. The detection of bone marrow autoantibodies of 2 patients in group B showed positive with 7.14%. The positive rate in group A was obviously higher than that in group B (p < 0.01). The ratios of CD19(+) and CD5(+) B lymphocyte in peripheral blood were significant higher in group A than that in group B and control group (p < 0.01), but there was no significant difference between groups B and control. It is concluded that the application of flow cytometry in detecting the autoantibodies of bone marrow cells and CD19(+) B-and CD5(+) B-lymphocyte in peripheral blood can provide reliable diagnostic evidence and detection measure for diagnosis and differential diagnosis of IRP, as well as may contribute to draw up more effective therapeutic strategy.
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PMID:[Clinical significance of flow cytometry in diagnosis of immunorelated pancytopenia]. 1937 90


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