Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.11.1.7 (peroxidase)
 65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The diagnosis of primitive hematologic malignancies in extramedullary sites (lymphoblastic lymphoma of T- or B-cell type and myeloid sarcoma) on paraffin-embedded tissue sections is difficult and often impossible because of the primitive morphology of the neoplastic cells. The authors studied 21 extramedullary tumors of lymphoid or myeloid blasts. They used a panel of 22 antibodies on frozen sections and 9 antibodies on paraffin sections to determine the spectrum of immunophenotypes and to develop a practical panel for diagnosis. All but two of the cases could be classified as lymphoid or myeloid using immunohistologic analysis. Thirteen cases were classified as lymphoblastic lymphoma/acute lymphoblastic leukemia (LBL/ALL); 10 were classified as precursor T (CD7+, CD3+/-, CD45+) and 3 as precursor B-cell (CD19+/-CD10+CD45-) type. Five cases were classified as myeloid sarcoma (CD13+ myeloperoxidase+, lysozyme+). Two LBL/ALL coexpressed either CD33 (1 case) or CD15 (1 case), and one myeloid sarcoma coexpressed TdT and CD7. One case appeared to be truly mixed lineage, coexpressing CD3 with myeloperoxidase and lysozyme, and two cases expressed no lineage-specific antigens. There were clinical differences between the three major tumor types, and within the category of T-precursor LBL/ALL, classification according to stage of thymocyte differentiation was associated with distinctive clinical features. In conclusion, the spectrum of immunophenotypes detected on frozen section was similar to that reported by flow cytometry on peripheral blood and bone marrow specimens. The most useful antigens on frozen sections were CD7 and CD3 (T cell), CD10 and CD19 (B cell), and CD13 (myeloid). TdT was coexpressed by one myeloid sarcoma and was undetectable in 40% of LBL/ALL. On paraffin sections, myeloperoxidase and lysozyme were reliable markers of myeloid lineage, but none of the markers used on paraffin sections distinguished between LBL/ALL of T- and B-precursor types. Both B-LBL/ALL and myeloid sarcomas were often CD45- on paraffin sections, which may be a obstacle in determining the diagnosis. These distinctions appear to have clinical relevance.
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PMID:Extramedullary tumors of lymphoid or myeloid blasts. The role of immunohistology in diagnosis and classification. 757 94

Individuals with Down syndrome have an increased incidence of leukemia compared to the general population. In addition, Down syndrome children may acquire a myeloproliferation that resembles acute leukemia that undergoes a spontaneous, durable remission. To clarify the relationship between these two disorders, the morphologic, immunophenotypic and cytogenetic characteristics of 28 patients with Down syndrome and the morphologic manifestations of acute leukemia were examined. Three cytomorphological groups were discerned. The first two groups consisted of five patients with acute lymphoblastic leukemia (group I) and three patients with acute myeloid leukemia (group II). These leukemias resembled those of non-Down individuals. The third and largest group (group III) consisted of 20 cases of acute myeloid leukemia that showed prominent megakaryocytic and/or erythroid differentiation and occurred in children under 6 years of age. The blasts in this group were non-reactive for myeloperoxidase or non-specific esterase and expressed CD7, CD34 and CD36 with variable expression of CD61, CD13 and CD33. Four patients in this group had an acquired trisomy 8. Four group III leukemias underwent a durable, spontaneous remission within 2 months of diagnosis. There were no morphologic differences between those leukemias in this group that progressed and those that remitted; however, all remissions occurred in newborns. It is concluded that Down syndrome children acquire a characteristic acute myeloid leukemia that has prominent megakaryocytic and/or erythroid differentiation and an unusual immunophenotype. This group of leukemias may undergo a durable, spontaneous remission in the newborn period.
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PMID:Acute leukemia and the transient myeloproliferative disorder associated with Down syndrome: morphologic, immunophenotypic and cytogenetic manifestations. 765 8

We describe 2 cases of "bilineal" crisis in chronic myelogenous leukemia (CML) with T cell and myeloid phenotypes. In both cases, morphocytochemically distinct myeloid and T lymphoid blast populations proliferated simultaneously in the phase of blastic crisis--myeloperoxidase (MPO)-positive, CD7+/CD33+ myeloblasts in the peripheral blood, and MPO-negative, periodic acid Schiff (PAS)-positive lymphoblasts in the lymph nodes. In each case, common karyotypes containing Ph1 translocation were demonstrated in both the peripheral blood and the lymph node samples. In Case 1, the lymph nodes were occupied by > 90% lymphoblasts, which were positive for CD2, cytoplasmic CD3 (cCD3), CD5 and CD7 and terminal deoxynucleotidyl transferase (TdT), but negative for myeloid antigens. Myeloblasts and T lymphoblasts showed an identical rearrangement of the bcr gene by Southern blotting analysis, although the clonal rearrangement of the T cell receptor (TcR)-delta gene was seen only in T lymphoblasts. In Case 2, simultaneous proliferation of myeloblasts and lymphoblasts was documented morphocytochemically in the lymph node, and a flow cytometric analysis revealed the coexistence of CD7+/CD33+ and CD7+/CD33- blast populations. Each blast population was enriched by antibody-conjugated immunomagnetic beads; the former was positive for MPO by 64% but negative for cCD3 and TdT, whereas the latter was positive for cCD3 and TdT but negative for MPO (< 1%). CD7+/CD33+ myeloblasts and CD7+/CD33- lymphoblasts showed an identical rearrangement of the bcr gene. Neither TcR-beta, TcR-gamma nor the TcR-delta gene was clonally rearranged in either population. These observations clearly indicate that T lymphoid and myeloid blasts share common Ph1-positive progenitors, and that Ph1-positive T lymphoid/myeloid progenitors are probably involved in the development of blastic transformation in some percentage of CML patients.
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PMID:T lymphoid/myeloid bilineal crisis in chronic myelogenous leukemia. 768 98

One of 8 to 12 pre-B ALL cells co-express CD13 and CD33 antigens, but such blasts do not express myeloperoxidase (MPO) even on electronmicroscopy or mRNA. MPO+ pre-B ALL is extremely rare (1/50-1/100), however a cell-line (Tahr87) was established in culture. In contrast, T-lineage blasts express CD13/33 antigens regularly in the pro-thymic stage (CD7+ 5+ 2+ 3- 4- 8- or more immature), and a limited expression of MPO is rather commonly detected particularly in recurrences. The co-expression of CD3 epsilon/MPO or CD3 epsilon/delta/MPO mRNA has been demonstrated. Thus, the regulation of MPO expression is of utmost importance in interpreting the phenotypes of leukemia/lymphoma. While testing the effects of several cytokines on MPO expression, IFN-gamma was found to suppress the gene expression of MPO in HL60 cells. This suppression was not accompanied by differentiation, termination of proliferation or reduction of cytochemical MPO+ cells, and was reversible. Among 22 cases of M1 AML blasts, 8 cases were HLA-DR(-). DR antigen was induced by the presence of a mixture of IFN-gamma, TNF-alpha and TPA in 4 cases, but not in the other 4 cases. The blasts of the latter 4 cases were always CD34(-), CD7(-) and CD45RA-/RO+, and constituted a distinct M1 subset which has not previously been reported.
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PMID:[Cytokine in phenotypic analysis of leukemia/lymphoma: suppression of gene expression of myeloperoxidase by IFN-gamma and subset of AML M1 defined by CD45RO+/RA-, CD7(-), CD34(-) and non-inducible HLA-DR antigen]. 768 32

We investigated the phenotypes of blast cells of 53 patients with acute leukemia by a modified streptavidin-biotin alkaline phosphatase (SAB-AP) labeling technique, using a panel of monoclonal antibodies [MoAb; anti-CD11b, CD13, CD14, CD33, CD34, CD41, CD3, CD7, CD10, CD19, anti-HLA-DR, and anti-myeloperoxidase (MPO)]. The selection of an optimal fixative solution for each antigen from five options of various combinations of formalin, acetone, methanol, and/or ethanol, successfully conserved cell morphology and improved specific reaction compared with the conventional methods which used a single fixative for multiple antigens. We compared the SAB-AP results with those obtained by flow cytometry (FCM) for surface markers in each case. High concordance rates for both positive and negative results were observed for each marker. However, positive reaction for some markers (anti-CD13, CD14, CD33, and CD34) were often noted only in the cytoplasm by the SAB-AP method, indicating that combination of these two methods is essential for the precise immunophenotyping of poorly differentiated leukemia cells.
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PMID:Usefulness of immunocytochemistry for phenotypical analysis of acute leukemia; improved fixation procedure and comparative study with flow cytometry. 771 39

In August, 1992, we established a leukemic cell line (NS-Meg) from a patient in megakaryoblastic transformation of Philadelphia chromosome-positive chronic myeloid leukemia. The NS-Meg cells were positive for alpha-naphthyl acetate esterase and periodic acid-Schiff (PAS) staining and for surface CD4, CD7, CD13, CD34, CD41a, and glycophorin A antigens. Ultrastructurally, the cells had alpha-granules, demarcation membranes, and platelet peroxidase activity. The NS-Meg cells spontaneously produced platelet-like particles which contained alpha-granules, mitochondria and dense bodies, strongly suggesting platelet production. Erythropoietin (Epo), granulocyte/macrophage colony stimulating factor(GM-CSF), and interleukin 3 (IL-3) promoted the growth of NS-Meg cells. Phorbol-12-myristate-13-acetate increased the expression of both CD41a and CD61 antigens. Ten-day exposure to Epo induced mature erythroblasts and red cells. These benzidine-positive cells were positive for hemoglobin F staining. Untreated NS-Meg cells expressed mRNA for the Epo receptor (EpoR), for GATA-1, and for alpha 1, alpha 2 and gamma globin genes. These results indicate that NS-Meg cells undergo terminal differentiation of both megakaryocytic and erythroid lineages. This cell line should be a very useful tool for the investigation of both megakaryocytic and erythroid maturation.
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PMID:A newly established megakaryoblastic/erythroid cell line that differentiates to red cells in the presence of erythropoietin and produces platelet-like particles. 771 48

We describe a patient with basophilic leukaemia following a 2-year period with myelodysplastic syndrome (refractory anaemia). The marrow showed 59.4% of blasts with 25.0% of mature and immature basophils. The leukaemic blasts contained granules, positively stained with toluidine blue but negative for peroxidase. The basophilic differentiation was confirmed by ultrastructural analysis demonstrating immature basophil granules. In addition, a morphological transition from immature blasts to more mature basophils was observed. Immunophenotypic analysis of blasts and basophils showed positive for CD5, CD7, CD13, CD33 and CD34. Cytogenetic investigation showed an abnormal karyotype, 46,XY,del(5)(q31q35), in 11% of the cells examined when the initial diagnosis of refractory anaemia was made. However, expansion of the same clone up to 100% was observed concomitantly with transformation to basophilic leukaemia.
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PMID:Transformation into acute basophilic leukaemia in a patient with myelodysplastic syndrome. 773 71

We describe our experience in the identification of 19 cases of AML-M0 categorized among 200 consecutive AML cases. Leukaemic cells from our cases were morphologically marked by agranular basophilic cytoplasm, finely dispersed chromatin and prominent nucleoli. In two cases heavily vacuolated and monocytoid-shaped blasts were also observed. Cytochemistry (MPO, SBB, alpha ANAE, alpha NBE, NASDCAE, AP, PAS) was negative in 14 cases, five cases expressing a very faint cytoplasmic positivity for alpha NBE (not exceeding 30% of the blasts) and alpha ANAE (not exceeding 41%) which was sodium fluoride resistant. In these five cases other monocytic markers (e.g. CD14) were not in favour of myelomonocytic differentiation. All the cases were anti-MPO positive at frequency > 10%. Phenotypic analysis also revealed myeloid features with all the patients having at least one myeloid antigen (CD13, CD33, CD15), Tdt was expressed in nine cases and CD7 in six cases. All cases but one were positive for CD34. Cytogenetic analysis, performed in 16 cases, showed no adequate growth in two cases and no consistent abnormality in four; among the remaining 10 cases no consistent abnormality was observed, the most common finding was trisomy 8 (two cases) and 4 (two cases) and aberrations of chromosomes 2, 3, 5, 7, 9, 12 and 21. No cases of (t9;22), Ph chromosome were observed. Interestingly three out of five patients with faint alpha NBE/alpha ANAE positivity relapsed as typical M4 (one case) or M5a (two cases).
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PMID:Minimally differentiated acute myeloid leukaemia (AML-M0): cytochemical, immunophenotypic and cytogenetic analysis of 19 cases. 781 3

Coexpression of myeloid, B-, and T-lineage associated markers was found in a patient with morphologically and cytochemically undifferentiated acute leukemia. Surface marker analysis using two-color immunofluorescence staining characterized blast cells to express CD34, CD38, CD117, and class II antigens, coexpressing TdT, CD4, CD7, CD13, CD19, and CD33. Cytoplasmic expression of myeloperoxidase, CD3, and CD22 could not be demonstrated. Monosomy for chromosome 7 was found by cytogenetic analysis. The absence of clonal rearrangements of immunoglobulin or T-cell receptor genes was shown by Southern blot analysis. Using a 3H-thymidine incorporation assay, DNA synthesis of leukemic blasts could be stimulated by IL-3, IL-6 and G-CSF in vitro. The present case did not offer specific criteria of lineage commitment. Corresponding to an equivalent counterpart in normal hematopoiesis, the involved cell population may reflect an early, most immature developmental stage within a multipotent progenitor cell compartment.
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PMID:Acute leukemia coexpressing myeloid, B- and T-lineage associated markers: multiparameter analysis of criteria defining lineage commitment and maturational stage in a case of undifferentiated leukemia. 786 61

We have established a novel human megakaryoblastic cell line, designated as MEG-A2, from a patient with megakaryoblastic crisis of Philadelphia (Ph) chromosome positive chronic myelogenous leukemia. MEG-A2 cells showed positive phenotypes for periodic acid Schiff and alpha-naphthylbutyrate esterase reactions, but were negative for myeloperoxidase and naphthol ASD chloroacetate esterase reactions. Flow cytometric analyses of cell surface markers revealed that MEG-A2 cells had a low level of GP IIb/IIIa expression as well as apparent expressions of CD4, CD7, CD13, CD33 and CD34 antigens, but no expression of GP Ib nor glycophorin A. Stimulation with phorbol 12-myristate 13-acetate (PMA) dramatically increased the expression of megakaryocyte-related markers such as HPL-3, J15, Pit-1, Y2/51 and AN51 in MEG-A2 cells. The PMA-stimulation also induced expression of platelet peroxidase (PPO) in MEG-A2 cells on electromicroscopic observation. Proliferative responses to granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3) or erythropoietin were observed, and the expression of GP IIb/IIIa was increased by stimulation with GM-CSF, IL-3, erythropoietin and interleukin-6 (IL-6). Protein S mRNA expression was seen in cultured cells on Northern blot analysis. Expression of platelet factor 4 mRNA was induced in PMA-stimulated cells, and a marked accumulation of protein was observed in the culture medium. In conclusion, a new cell line, MEG-A2, belongs to the relatively immature megakaryocytic lineage and has markedly increased megakaryocytic characteristics with PMA stimulation.
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PMID:Establishment and characterization of an immature human megakaryoblastic cell line, MEG-A2. 786 73


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