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

It has previously been shown that patients with aplastic anemia (AA) have a stem cell defect both of proliferation and differentiation. This has been shown by long-term bone marrow (BM) culture, long-term initiating cell assays, and committed progenitor assays. We present, for the first time, data on megakaryocyte (Mk) colony formation from purified BM CD34(+) cells from patients with AA. The results are compared with those from normal controls and from patients with paroxysmal nocturnal hemoglobinuria (PNH) and the myelodysplastic syndromes (MDSs). Those treated for AA had previously received immunosuppression (antithymocyte globulin and/or cyclosporin). No patients had received bone marrow transplantation. A total of 13 AA patients (five untreated, eight treated), six PNH, six MDS, and 13 normal donors were studied. BM CD34(+) cells were purified by indirect labeling and then cultured in a collagen-based Mk assay kit (MegaCult-C, StemCell Technologies). The cultures were fixed on day 12, and the Mk colonies were identified by the alkaline phosphatase anti-alkaline phosphatase technique using the monoclonal antibody CD41 (GP IIb/IIIa). The slides were scored for Mk colony-forming units (CFU-Mks) (3-20 and >20 cells), Mk burst-forming units (BFU-Mks) (>50 cells), and mixed colonies. The results show that total Mk colony formation in AA was significantly lower than in normal donors (p<0.0001), both in untreated patients/nonresponders to treatment (p = 0.0001) and in complete/partial responders (p<0.002). There was no significant difference in Mk colony formation in treated and untreated patients (p = 0.05). Patients with AA had a lower total colony formation than PNH patients (p = 0.0002). PNH patients exhibited lower colony formation than normal controls (p = 0.03), as shown by MDS patients, although the considerable number of variables resulted in a lack of statistically significant difference from normal controls (p = 0.2). We have now shown that Mk colony formation from purified BM CD34(+) cells is significantly reduced, supporting previous evidence that AA results from a stem cell defect.
 ...
PMID:In vitro proliferation and differentiation of megakaryocytic progenitors in patients with aplastic anemia, paroxysmal nocturnal hemoglobinuria, and the myelodysplastic syndromes. 1107 31

Cyclosporin A (CsA) is used to prevent rejection in transplantation and to treat autoimmune and hematologic diseases such as aplastic anemia. However, the tumor growth-promoting effect of CsA remains controversial. We report the case of a 24-year-old man who developed acute lymphoblastic leukemia of precursor-T-cell origin after 75 months of treatment with CsA for aplastic anemia. The surface antigen phenotype of his leukemic cells was CD2+, CD3+, CD5+, CD7+, CD4-, CD8-, CD10-, CD20-, CD34-, CD41-, and CD56-. Southern blot analysis revealed a monoclonal rearrangement of T-cell receptor-Jgamma nongermline fragments in HindIII digestion.
 ...
PMID:T-Cell type acute lymphoblastic leukemia following cyclosporin A therapy for aplastic anemia. 1137 36

The aim of this study was to explore application value of detecting platelet associated antibody and platelet membrane glycoprotein in the diagnosis and prognosis for immune thrombocytopenia. The platelet associated immunoglobulin (PAIg) and platelet membrane glycoprotein (CD41, CD61, GPIIb/IIIa) in 76 cases of immune thrombocytopenia and 30 healthy subjects were determined by FCM. The results showed that PAIg level in ITP patients included PAIgG (31.25 +/- 18.06)%, PAIgM (32.41 +/- 15.51)%, PAIgA (23.39 +/- 16.67)% which were remarkedly higher than in health control (10.48 +/- 5.05)%, (9.40 +/- 4.42)% and (7.23 +/- 3.61)% (P < 0.001). In patients with secondary immune thrombocytopenia (chronic aplastic anemia, SLE, Evans syndrome, liver cirrhosis hypersplenism, etc), PAIg level was higher than that in control group, while the platelet membrane glycoprotein in the blood of these patients was lower than that in control group. The level of PAIg decreased (P < 0.05) after treatment, but platelet membrane glycoprotein increased (P < 0.01). The result suggested that measurements for platelet membrane glycoprotein and platelet associated antibody by FCM were practical with high sensitivity, rapidity and simplicity used as a routine method in diagnosis and evaluation of the therapeutic effects in immune thrombocytopenia patients.
 ...
PMID:[Significance of detecting platelet associated antibody and platelet membrane glycoprotein for diagnosis of immune thrombocytopenia]. 1515 39

The numbers of antibody-binding sites of platelet glycoprotein (GP) IIb/IIIa on circulating platelets were analyzed using 4 kinds of antibodies in 34 aplastic anemia (AA) patients, 20 idiopathic thrombocytopenic purpura (ITP) patients, and 14 normal controls. The numbers of antibody-binding sites of CD41, CD41a, CD41b, and CD61 on platelets of the AA patients were less than in the normal controls (p <0.001). In the ITP patients, the numbers of sites for CD41 and CD41a were less than in normal controls (p <0.05). There were significant positive correlations between CD41 and CD41a, CD41b, and CD61 in the 3 groups. There were significant negative correlations between CD41 and CD41b and between CD41a and CD41b in the normal controls, but not in the AA or ITP patients. In summary, the numbers of the 4 antibody-binding sites of GPIIb/IIIa on platelets of AA and ITP patients are different from those in normal controls. Measurements of the antibody-binding sites of GPIIb/IIIa are not necessary for the differential diagnosis of AA and ITP. However, the differences in correlations between the numbers of epitopes in AA and ITP patients suggest that the epitopes of GPIIb/IIIa are altered in these diseases.
 ...
PMID:Quantitative comparisons of antibody-binding sites of platelet glycoprotein IIb/IIIa in aplastic anemia and idiopathic thrombocytopenic purpura. 1831 75

A morphometric analysis was performed on aspirated clots of bone marrow to identify the presence of micromegakaryocytes after immune staining with a monoclonal antibody raised against CD41. Quantitative and qualitative abnormalities of micromegakaryocytes were assessed based on both standard staining and CD41 immune staining. Micromegakaryocytes were largely detected in bone marrow from patients with myelodysplastic syndrome (MDS), while almost no micromegakaryocytes were present in aplastic anemia. CD41 immune staining clearly improved the efficiency of micromegakaryocyte detection under any conditions, showing strong potential as a tool for the auxiliary diagnosis of MDS and differentiation of MDS from pancytopenia, particularly aplastic anemia(AA).
 ...
PMID:CD41 immune staining of micromegakaryocytes improves the diagnosis of myelodysplastic syndrome and differentiation from pancytopenia. 2967 88