1/8. Sialyl-Tn- and neuron-specific enolase-positive minimally differentiated erythroleukemia.Flow cytometric, immunochemical and molecular studies were performed on leukemic blasts from a patient with minimally differentiated erythroleukemia (AML-M6v). The blasts expressed CD36 and CD71 but not lymphoid antigens, myeloid antigens, CD41 or glycophorin A. Analysis of carbohydrate antigens showed that the blasts expressed the sialyl-Tn antigen. immunochemistry revealed that the blasts had neuron-specific enolase (NSE). serum sialyl-Tn and NSE levels were markedly increased. Finally, an erythroid lineage was confirmed in the presence of alpha-globin messages in the blasts. Sialyl-Tn and NSE expression in leukemic blasts may be useful to identify AML-M6v.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/8. HLA-DR expression by platelets in acute idiopathic thrombocytopenic purpura.Induction of expression of MHC class II antigens on the surface of cells that do not ordinarily express these proteins has been implicated in the pathogenesis of autoimmunity in diabetes mellitus and autoimmune thyroiditis. Platelets express class I but not class II hla antigens. In this report, we describe a child with acute idiopathic thrombocytopenic purpura who at the time of the thrombocytopenic episode had class II (HLA-DR) antigens on his platelets. Following recovery, the hla-dr antigens were no longer present on the platelets. We postulated that class II had been induced on his megakaryocytes by a cytokine such as interferon gamma, and that the induced expression of class II antigens contributed to the autoimmune disorder. To substantiate this possibility we next studied class I and II antigen expression on an erythroleukaemia cell line (HEL), which has many megakaryocytic features. Following treatment of HEL cells with interferon gamma, class I expression was increased and hla-dr antigens were induced. These observations suggest that cytokine-mediated induced HLA-DR expression may contribute to the pathogenesis of a subset of thrombocytopenias.- - - - - - - - - - ranking = 1.75keywords = antigen (Clic here for more details about this article) |
3/8. A new murine monoclonal antibody for the diagnosis of erythroleukemia.The authors have developed a murine monoclonal antibody, RC-82.4, against an antigen expressed by a human erythroleukemia cell line OCI-MIR. The antibody reacts with an antigen expressed by proerythroblasts, normoblasts, and some reticulocytes but not expressed in erythrocytes, granulocytes, monocytes, megakaryocytes, plasma cells, or lymphocytes. The authors have established an immunocytochemical method for studying bone marrow smears with RC-82.4. By studying bone marrow smears from 11 patients with M-6 erythroleukemia and 104 patients with various other hematologic and nonhematologic malignancies, the authors have found that RC-82.4 has great sensitivity and specificity in recognizing erythroid differentiation in blasts. The authors have used RC-82.4 and antihemoglobin antibodies to identify erythroblasts in acute and secondary acquired cases of erythroleukemia that would have been unclassifiable by morphologic and all other conventional cytochemical and immunocytochemical criteria.- - - - - - - - - - ranking = 0.5keywords = antigen (Clic here for more details about this article) |
4/8. Childhood erythroleukemia. Studies on pathogenesis using colony assays.Marrow hematopoiesis was examined in two infants with erythroleukemia (EL) using cell culture colony assays. At diagnosis, marrow from both yielded normal to increased numbers of granulocytic colonies (CFU-C), erythroid bursts (BFU-E), and mixed colonies (CFU-GEMM), which contrasted sharply with the reduced growth in eight other newly diagnosed patients with acute leukemia. BFU-E proliferation and hemoglobinization proceeded normally in culture and was entirely erythropoietin-dependent. CFU-C colony cellular composition showed normal granulopoiesis in various stages of development. Despite low numbers of morphologically recognizable blasts in the aspirates, they were readily identified in a blast colony assay because of their high plating efficiency and high index of self-renewal on replating. Blast cells in all cultures had myeloblastic morphology, were peroxidase positive, and expressed the granulocytic-specific My-1 antigen. monosomy 7 was seen in fresh and cultured blast cells but not in lymphocytes, indicating a clonal proliferation. After chemotherapy-induced remission, blast colonies and monosomy 7 could no longer be detected. It appears that the integrity and function of the normal hematopoietic progenitor pool were preserved in these patients with EL. The abnormal myeloblastic proliferation was expressed actively in colony assays and was useful diagnostically in these cases because marrow morphology was nondiagnostic. In these patients, EL seems to be a misnomer since the findings are suggestive of acute myeloblastic leukemia with secondary erythroid and granulocytic hyperplasia.- - - - - - - - - - ranking = 0.25keywords = antigen (Clic here for more details about this article) |
5/8. Erythroleukemia with high fetal hemoglobin after therapy for ovarian carcinoma.The authors report the association of erythroleukemia (FAB M6) and fetal hemoglobin (HbF) level of at least 65% after therapy for ovarian carcinoma. The patient's erythrocytes had many signs of reversion to fetal-like erythropoiesis including: elevated HbF with a fetal G gamma/A gamma (gly/ala) of 3/1, low hemoglobin a2 (HbA2), macrocytosis, and increased i antigen. These data and data from other case reports suggest that elevation of HbF to greater than 25% with reversion to fetal-like erythropoiesis is useful in differentiating erythroleukemia from other preleukemic disorders.- - - - - - - - - - ranking = 0.25keywords = antigen (Clic here for more details about this article) |
6/8. Modifications of B, I, i, and Lewisb antigens in a patient with DiGuglielmo's erythroleukemia.Loss of red blood cell antigens has been documented in patients with acute myelocytic leukemia and includes loss of A, B, and H antigens in the ABO system as well as antigens of the Rh, MNSsU, Lewis and Ii systems. The following case represents partial loss of the B, I and Lewisb antigens in a patient with erythroleukemia. Also, the loss of the I antigen was associated with a concomitant increase in i antigen, a known but rare finding. These changes within the ABO, Ii, and Lewis systems do not appear to be coincidental, as these blood group systems share a common biochemical backbone.- - - - - - - - - - ranking = 2.5keywords = antigen (Clic here for more details about this article) |
7/8. Pathogenetic significance of "pure" monosomy 7 in myeloproliferative disorders. Analysis of 14 cases.monosomy 7 is frequent in acute myeloid leukaemia (AML) and in preleukaemic dysmyelopoietic syndromes but often it is not the only chromosome anomaly associated with these conditions. We report 14 patients with "pure" monosomy 7 and their clinical and haematological data are analysed in order to clarify the possible implications of this chromosome anomaly. The following points are considered: 1) In spite of the apparent variability of clinical forms in which monosomy 7 is found, several characteristics are common to all monosomy 7 patients, i.e. the presence of a preleukaemic phase and blood and marrow features suggesting the early involvement in the disease of all marrow cell lines. The different diagnoses associated with monosomy 7 are correlated with different steps of a unique myeloproliferative disease whose typical course can be reconstructed. 2) monosomy 7 has a negative prognostic value. When it is found in a preleukaemic disorder it indicates a high risk of progression to AML, while in AML it implies recurrent infections, poor response to therapy and short survival. 3) The significance of the lack of Colton blood group antigens in monosomy 7 patients is discussed, with particular regard to the fact that the patients in whom this lack was found are the only ones who had not received transfusions in the months before the tests were done. 4) The finding of defective neutrophil chemotaxis in monosomy 7 patients is confirmed and the clinical importance of this fact is emphasized. 5) The data on the 14 patients support the opinion that AML, in general, is heterogeneous in origin. It is postulated that monosomy 7 is a marker of a specific pathogenetic pathway of AML, which implies the beginning of the malignancy in a pluripotent stem cell.- - - - - - - - - - ranking = 0.25keywords = antigen (Clic here for more details about this article) |
8/8. Ischaemic colitis and lung infiltrates caused by extramedullary haematopoiesis in a patient with an acute erythroid leukaemia following polycythaemia vera.A patient with 'spent' polycythaemia vera showed extensive extramedullary haematopoiesis (EMH) in non-haematopoietic tissue clinically resulting in an ischaemic colitis and respiratory symptoms due to lung infiltrates. On laboratory investigation, the EMH also included immature erythroblasts due to acute erythroid leukaemia. It is hypothesised that the abnormal homing of erythroid progenitors might be related to the abnormal expression of antigens, such as CD36.- - - - - - - - - - ranking = 0.25keywords = antigen (Clic here for more details about this article) |