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)

Cyclosporine (CyA) therapy has been shown to be effective in some patients with aplastic anemia. In an attempt to characterize aplastic patients likely to benefit from CyA therapy, we examined bone marrow mononuclear cells (BMMC) obtained before therapy from 23 patients with aplastic anemia, who were treated with CyA alone. Expression of four myelosuppressive cytokines, including tumor necrosis factor (TNF), lymphotoxin, macrophage inflammatory protein-1 alpha (MIP-1 alpha), and interferon-gamma (IFN-gamma) was examined using polymerase chain reaction (PCR)-assisted messenger RNA (mRNA) amplification. mRNA for TNF, lymphotoxin, and MIP-1 alpha was readily detectable at variable levels in BMMC from normal and transfused controls as well as in BMMC from aplastic patients. In contrast, IFN-gamma mRNA was only demonstrable in BMMC from some patients with aplastic anemia, irrespective of a history of transfusions. Of 13 patients who responded to CyA therapy and achieved transfusion-independence, IFN-gamma mRNA was detected in 12 patients, whereas the mRNA was only detectable in 3 of 10 patients refractory to CyA therapy (P = .003, Fisher's exact test). Follow-up examination of BMMC obtained from seven CyA-responding patients after hematologic remission showed disappearance of IFN-gamma mRNA in four patients. These results suggest that detection of IFN-gamma gene expression in pretreatment BMMC from aplastic patients using PCR may be helpful in predicting a good response to CyA therapy.
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PMID:Interferon-gamma gene expression in unstimulated bone marrow mononuclear cells predicts a good response to cyclosporine therapy in aplastic anemia. 158 5

The aim of the present study was to compare the response of bone marrow (BM) lymphocytes from patients with aplastic anemia (AA) or normal controls to increasing doses of antilymphocyte globulin (ALG) or phytohemagglutinin (PHA). For this purpose BM T-enriched cells from 11 AA patients and 9 normal individuals were incubated with ALG (0-1000 micrograms/ml) or PHA (0%-10%) for 1 day, and the supernatants were tested for suppression/enhancement of granulocyte-macrophage colony-forming unit (CFU-GM) growth and for release of granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) assayed with the enzyme-amplified sensitivity immunoassay (EASI). The production of colony-stimulating activity (CSA) by T cells primed with ALG and tested in the absence of exogenous GM-CSF correlated with the dose of ALG in priming cultures up to 14% EG (100% EG = CFU-GM growth with 30 ng/ml of GM-CSF). The amount of GM-CSF in the supernatants paralleled their capacity to sustain CFU-GM growth (up to 3.5 ng/ml of GM-CSF). Production of CSA or GM-CSF from T cells primed with PHA was significantly lower. Supernatants of PHA-primed T cells, when added to normal BM cells in the presence of exogenous GM-CSF, produced a dose-dependent inhibition of CFU-GM growth (down to 13% +/- 10% EG). The same supernatants contained detectable amounts of IFN-gamma and TNF-alpha (21 +/- 6.7 IU/ml and 4.6 +/- 2.9 ng/ml, respectively). IFN-gamma production from severe AA (SAA) T cells in response to PHA was significantly superior to the IFN-gamma production from normal T cells (21 +/- 6.7 IU/ml vs 9.5 +/- 7.1 IU/ml, p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:In vitro response of T cells from aplastic anemia patients to antilymphocyte globulin and phytohemagglutinin: colony-stimulating activity and lymphokine production. 190 92

To evaluate the role of cytokines in patients with aplastic anemia, colony stimulating activities (CSA) and interferon-gamma (IFN-gamma) in cultured media of lymphocytes with phytohemagglutinin (PHA-LCM) were measured with methylcellulose culture method in 20 patients (age 3 to 69 years). The CSA for granulocyte/macrophage (GM-CSA) in patients was equivalent to that of normal donors, while low burst promoting activity (BPA) was observed in PHA-LCM from 7 adult patients (61 +/- 17%). The ability of BPA production varied widely in 13 children (97 +/- 37%). In some patients, low production of BPA improved after successful treatment of antilymphocyte globulin. The IFN-gamma in PHA-LCM disclosed no significant difference between patients and normal donors. From these results, low production of BPA may have a role in the development of AA in certain patients. It is also suggested that therapy with recombinant cytokines such as GM-CSF and IL-3, detected as BPA in our culture system, could be effective for those patients.
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PMID:[Effect of humoral factors produced by lymphocytes on hematopoietic progenitor cells--productive ability of colony stimulating activities and interferon-gamma by blood mononuclear cells in patients with aplastic anemia]. 211 75

The expression of lymphocyte surface markers as well as the production of interleukin-2 (IL-2) and interferon-gamma (IFN) by mitogen-stimulated peripheral blood mononuclear cells (MNC) have been studied in five children with constitutional aplastic anemia. A significantly reduced T4/T8 ratio was found and two of five patients also had a reduced percentage of B cells. One patient had a high percentage of HLA-DR positive T8+ cells, very suggestive of a high degree of circulating activated T suppressor/cytotoxic cells. IL-2 production was reduced in two patients, whereas IFN production was only reduced in one of these. The abnormalities found correlate with the duration of the bone marrow failure. The patients with the longest duration of bone marrow failure also exhibited the lowest T4/T8 ratio. No spontaneous IFN production was detected in any of the patients. There was no clinical benefit or reversal of the immune abnormalities during and following treatment with cimetidine and cyclosporine A in two patients.
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PMID:Lymphocyte subpopulations and lymphokine production in children with constitutional aplastic anemia. 248 52

Circulating mononuclear cells from a patient developing severe aplastic anemia during the course of non-A, non-B hepatitis were found to be virtually entirely composed of in vivo activated suppressor T cells (Ia+T8+). These cells were used to establish a new permanent cell line, termed SMAA, by using phytohemagglutinin, Ebstein-Barr virus-transformed irradiated B cells, allogeneic irradiated peripheral blood mononuclear cells, and recombinant interleukin 2 to investigate the relationship of aplastic anemia-derived circulating T cells to bone marrow failure. SMAA cells, now in continuous culture for more than 9 mo, were shown to inhibit proliferation of purified myeloid progenitors and their differentiation into early and late appearing neutrophil and eosinophil colonies by 90%, whereas monocyte colonies were much less affected. Similarly, growth of erythroid colonies and bursts was almost completely inhibited, as was anti-mu-induced B cell proliferation and lectin-induced T cell proliferation. This inhibition of hematopoiesis was mediated by the release of a soluble factor that was sensitive to acid (pH 2), heat (56 degrees C), and trypsin. Monoclonal and polyclonal antibodies to interferon-gamma could abrogate the inhibitory effects of SMAA supernatant, but more than 10(4) neutralizing U/ml had to be added. The effects of SMAA could be duplicated by adding 10(4) U/ml of purified recombinant interferon-gamma to colony and proliferation assays. The concentration of interferon-gamma in SMAA supernatant was estimated to be greater than 3 X 10(3) National Institutes of Health reference U/ml by immunoradiometric assay. These results demonstrate that some patients with aplastic anemia have circulating T cells that are capable of prolonged in vitro secretion of interferon-gamma causing severe inhibition of in vitro hematopoiesis, and these cells can be expanded into permanent lines for studies on their regulatory properties.
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PMID:Establishment of an interleukin 2-dependent T cell line derived from a patient with severe aplastic anemia, which inhibits in vitro hematopoiesis. 293 4

T-cell-mediated inhibition of granulomonopoietic progenitors (CFU-GM) was studied in vitro in 27 patients with severe aplastic anaemia (AA). In nine out of 13 responders to anti-thymocyte globulin (ATG), cultured T-cells obtained prior to therapy, as well as their conditioned medium strongly suppressed both normal allogeneic and autologous CFU-GM (the latter obtained after marrow recovery). Addition of anti-interferon-gamma to the cultures abolished the suppressive effect on CFU-GM. After ATG therapy, no similar inhibitory effect was detected. Employing the panning method with monoclonal antibodies (CD4+ for inducer/helper and CD8+ for cytotoxic/suppressor T-cells) we were able to show that the cells responsible for in vitro CFU-GM inhibition were included in the cytotoxic/suppressor T-cell subpopulation. Cultured T-cells and their conditioned medium obtained from 14 non-responders to ATG did not show CFU-GM suppression. The mean interferon (IFN) levels in the T-cell conditioned media of ATG-responders was 625 +/- 125 mu/ml while in non-responders the level was 45 +/- 15 mu/ml (normal control levels 43 +/- 24 mu/ml). Freshly isolated peripheral blood lymphocytes from either group did not show any in vitro inhibitory effect. The response rate to ATG was statistically significant when the generation in culture of high versus low IFN production was compared (P = 0.0001). Experiments with T-cells obtained from heavily transfused thalassaemia major, and myelodysplastic syndrome patients, as well as normal volunteers, also did not demonstrate any suppression of CFU-GM. Our results indicate that the response rate to ATG is significantly higher in patients with AA who have an abnormal regulation of interferon-gamma (g-IFN) production.
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PMID:In vitro interferon-gamma production by cultured T-cells in severe aplastic anaemia: correlation with granulomonopoietic inhibition in patients who respond to anti-thymocyte globulin. 313 95

To determine the effect of recombinant human granulocyte-colony stimulation factor (rhG-CSF) on the immune system, serum immunoglobulins, lymphocyte subsets, and serum cytokines were analyzed in eight pediatric patients with aplastic anemia (AA) during 8-week rhG-CSF therapy. The rhG-CSF was administered either subcutaneously (200 micrograms/m2 x 4 weeks, followed by 400 micrograms/m2 x 4 weeks) or intravenously (400 micrograms/m2 x 4 weeks, followed by 800 micrograms/m2 x 4 weeks). In response to rhG-CSF therapy, neutrophil counts exceeded the pretreatment counts by twofold during the first week except for one case that did not attain twofold increase until day 41. While serum IgG and IgA were not affected, serum IgM was elevated during treatment in six of the eight cases to more than 1.2-fold basal levels (P < 0.04); however, there was no increase in serum interleukin (IL)-6 and interferon-gamma levels. On the other hand, CD56 positive NK cells significantly dropped from 7.7% to 4.5% (P < 0.02). These results indicate that systemic administration of rhG-CSF affects not only the neutrophil count, but also serum IgM levels and the natural killer cell population in patients with AA.
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PMID:Effect of recombinant human granulocyte-colony stimulation factor (rhG-CSF) on immune system in pediatric patients with aplastic anemia. 752 Feb 60

In some patients with aplastic anemia (AA), hematopoietic function is dependent on continuous administration of cyclosporine A (CyA). These AA patients may have T lymphocytes whose myelosuppressive effect is mitigated by CyA. We established a total of 29 T cell clones from the bone marrow of a CyA-dependent AA patient in relapse. Some of the CD4+ T cell clones demonstrated a specific proliferative response to irradiated autologous bone marrow cells enriched for CD34+ cells (CD34(+)-rich cells) obtained from the patient in remission. One of the T cell clones showing the best proliferative response to CD34(+)-rich cells carried the T cell receptor V beta 17 and produced interferon-gamma (IFN-gamma) only when cultured with autologous CD34(+)-rich cells. This T cell clone inhibited colony formation by colony-forming unit-granulocyte/macrophage (CFU-GM) and burst-forming unit-erythroid (BFU-E) by approximately 60% when it was cultured with autologous CD34(+)-rich cells in methylcellulose medium, although the clone did not exhibit direct cytotoxicity to the CD34(+)-rich cells. The inhibition of in vitro hematopoietic progenitor cell growth by the T cell clone was partially abrogated by the addition of CyA to the culture. These findings suggest that in some patients with CyA-dependent AA, CD4+ T cells autoreactive to hematopoietic progenitor cells exist and may play an important role in the pathogenesis of bone marrow failure.
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PMID:Establishment of a CD4+ T cell clone recognizing autologous hematopoietic progenitor cells from a patient with immune-mediated aplastic anemia. 772 Aug 14

Five patients with severe aplastic anaemia (SAA) who, simultaneously (n = 3) or consecutively (n = 2), presented with multiple sclerosis (MS) (n = 2) or immune hyperthyroidism (IHT) (n = 2) or subacute thyroiditis (n = 1) are described. Two female patients with MS developed SAA after a small dose of azathioprine. Another patient simultaneously presented with IHT and SAA. SAA and MS responded to cyclosporine while IHT required 131I. Relapsing SAA in 1 patient with MS was treated with antithymocyte globulin (ATG) which induced acute exacerbation of MS. Despite the low total dose of ATG (31.5 mg/kg), complete remission of SAA was obtained. Two other patients developed thyroid disorders, 42 and 106 months after successful immunosuppression with ATG/high-dose methylprednisolone. IHT and subacute thyroiditis were successfully treated with 131I or prednisolone, respectively, without recurrence of SAA in both cases. These are the first documented cases of SAA evolving in the course of MS while the coincidence with IHT was already described. Since enhanced expression of interferon-gamma plays a crucial role in SAA as well as in MS and in IHT, similar pathogenetic principles may apply for these seemingly unrelated disorders.
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PMID:Coincidence of severe aplastic anaemia with multiple sclerosis or thyroid disorders. Report of 5 cases. 787 51

Plasma levels of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) were determined in healthy individuals and patients with aplastic anemia (ApAn). IFN-gamma was not detected in normal peripheral blood plasma (PBP) or bone marrow plasma (BMP) and was present in PBP from only 2 of 22 patients and in BMP from 1 of 14 patients and the levels were low (< 1.5 U/ml). Elevated levels of TNF-alpha were present in BMP and PBP from patients but not in control (healthy donor) PBP and BMP. Eleven of twenty-four patients had elevated levels of TNF-alpha in their PBP and 6 of 13 patients had detectable levels of TNF-alpha in their BMP. Only one of the 14 healthy control donors had detectable TNF-alpha and the level was very low (7 pg/ml), while 13 of the 27 ApAn patients had detectable TNF-alpha (P = .009, chi-square test). Not surprisingly, the centers of the distributions of TNF-alpha concentrations of the controls and ApAn patients differed significantly (P < .017 for control and patient PBP and P < .056 for control and patient BMP, Wilcoxon rank-sum test). Spontaneous production of IFN-gamma and TNF-alpha by cultured bone marrow mononuclear cells was observed in four of seven patients but not in the six healthy controls (P = 0.026). Spontaneous production of IFN-gamma and TNF-alpha by cultured peripheral blood mononuclear cells from patients and controls was however similar. Phytohemagglutinin (PHA)-induced production of IFN-gamma and TNF-alpha by cultured mononuclear cells did not differ significantly between ApAn patients and normal controls. The significance of overproduction of TNF-alpha in the pathophysiology of ApAn is discussed.
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PMID:Detection of tumor necrosis factor-alpha in bone marrow plasma and peripheral blood plasma from patients with aplastic anemia. 825 9


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