The study was aimed to investigate the fusion gene transcript and immunophenotypic characteristics of the mixed linage leukemia (MLL)-rearranged positive childhood acute lymphoblastic leukemia (ALL). The incidence of MLL rearrangement in 601 cases of ALL patients was detected by the multiple-nested polymerase chain reaction (PCR); the subtypes and features of the fusion gene transcript were analyzed by PCR products sequencing; the immunophenotypic characteristics at diagnosis were compared between the 22 MLL rearrangement positive of ALL patient, 30 negative control which selected randomly from the patients whose fusion gene could not be detected in the same term and 43 pro-B-ALL patients. The results showed that the incidence of MLL positive ALL was 3.66%, constituted 29.9% of the pro-B-ALL. The MLL rearrangement positive 20 B-ALL patients were all CD10 negative; the number of patients who carried CD13, CD33 and CD34 was lower than that of pro-B-ALL who had no fusion gene, whereas the expression of CD20, CD22, CD2, CD5, CD7 showed no difference. 4 kind partner genes of MLL-AF4, AF9, AF10 and ENL were detected. The fusion loci of MLL gene were mainly located at the exon 6, 7, 8 and many kind of fusion loci of MLL may exist in one patient; whereas its partner gene fusion loci were relatively single. A transcript contains a random insert sequence existed in a transcript of one MLL-AF10+ patient. It is concluded that though incidence of MLL rearrangement is low, but it has a variety of fusion transcripts, the ALL patients has unique biological characteristics at immunophenotype and fusion transcript.
Adolescent ; Child ; Child, Preschool ; Gene Rearrangement ; Humans ; Immunophenotyping ; Infant ; Myeloid-Lymphoid Leukemia Protein ; genetics ; immunology ; Oncogene Proteins, Fusion ; genetics ; immunology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; immunology

To evaluate the expression of cytoplasmic CD79a (CyCD79a) and other commonly used B-lymphoid immunomarkers including cytoplasmic CD22 (CyCD22), CD19, CD20 and CD10 in various acute leukemia cells and to define the most sensitive and specific markers in the diagnosis of precursor B-cell acute lymphoblastic leukemia (pB-ALL), the immunophenotypic data from 221 de novo adult and pediatric acute leukemia patients as studied using multi-parameter flow cytometry in addition to routine morphologic and enzyme cytochemical assay, were retrospectively analyzed. Cytogenetic and/or molecular biological data in all 45 cases of acute promyelocytic leukemia (APL) and 13 cases of acute leukemia suspected as AML with the fusion genes such as AML1/ETO and CBFbeta/MYH11 were investigated. The results showed that CyCD79a and CyCD22 were the most sensitive and specific markers respectively for pB-ALL. Expression of CyCD79a was seen in 100% of 58 cases of pB-ALL. At the same time, none (0%) of all 147 cases of acute myeloid leukemia (AML) and 15 cases of precursor T-cell acute leukemia (pT-ALL) was positive for CyCD22. The conclusion is made that united detection of CyCD79a and CyCD22 is the optimal immune combination for the diagnosis pB-ALL and the distinguishing pB-ALL with AML and pT-ALL.
Acute Disease ; B-Lymphocytes ; immunology ; Biomarkers, Tumor ; immunology ; CD79 Antigens ; immunology ; Cytoplasm ; immunology ; Flow Cytometry ; Humans ; Immunophenotyping ; Karyotyping ; Leukemia, Myeloid ; genetics ; immunology ; pathology ; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma ; immunology ; metabolism ; pathology ; Sialic Acid Binding Ig-like Lectin 2 ; immunology

Gene rearrangement analysis using Southern-blot hybridization technique is a standard method for evaluating clonal receptor gene rearrangement. Both clonality and lineage can be identified in lymphoid neoplasms by the demonstration of one or more rearranged antigen receptor genes of the immunoglobulin supergene family-immunoglobulin and T-cell receptor genes. To evaluate the diagnostic applicability of antigen receptor gene rearrangements in the diagnosis of malignant lymphomas and leukemias, the authors performed a gene rearrangement analysis of 54 cases by southern blot hybridization technique. One or two clonally rearranged bands were detected in the malignant lymphomas and in the lymphoblastic leukemias with a false-negative rate of 13.8%. No clonal, rearranged band was detected in benign reactive hyperplasias, carcinomas or non-lymphocytic leukemias. Rearrangement analysis could resolve the lineage, clonality and stage of differentiation of malignant lymphoid neoplasms.
Gene Rearrangement ; *Gene Rearrangement, T-Lymphocyte ; *Genes, Immunoglobulin ; Human ; Leukemia/*genetics/immunology ; Lymphoma/*genetics/immunology ; Support, Non-U.S. Gov't

In order to analyze the distribution and clonal expansion of TCR Vbeta subfamily T cells in patients with acute promyelocytic leukemia (APL) in vivo and in vitro after T cell culture, the peripheral blood mononuclear cells from 3 APL patients were expanded by rhIL-2 and anti-CD3 antibody using liquid T lymphocytes culture technique. The complementary determining region 3 (CDR3) of TCR beta with variable region genes was amplified in T cells from 3 APL cases before and after T cell culture by using RT-PCR. The positive products were further analyzed to identify the clonality of T cells by genescan. The results showed that only a part of 24 Vbeta subfamilies was detected in T cells from the patients, and some Vbeta subfamily T cells could be identified after T cells culture. The clonal expansion T cells in some TCR Vbeta subfamilies could be found in all patients. The similar oligoclonal expansion of Vbeta1, Vbeta3, Vbeta7, Vbeta16 and Vbeta20 T cells was detected in two cases at different time points after T cell culture. It is concluded that the restricted expression of TCR Vbeta subfamily in T cells from patients might be the common feature in leukemia. Some Vbeta subfamily T cells could be induced after T cells culture in vitro. The continual clonal expansion of TCR Vbeta subfamily T cells at different time points after T cells culture could be a specific immune response of patients T cells related to the specific APL cell associated antigen.
Humans ; Leukemia, Promyelocytic, Acute ; genetics ; immunology ; Lymphocyte Activation ; Receptors, Antigen, T-Cell, alpha-beta ; genetics ; T-Lymphocytes ; immunology

RNA helicases are involved in almost every aspect of RNA, from transcription to RNA decay. DExD/H-box helicases comprise the largest SF2 helicase superfamily, which are characterized by two conserved RecA-like domains. In recent years, an increasing number of unexpected functions of these proteins have been discovered. They play important roles not only in innate immune response but also in diseases like cancers and chronic hepatitis C. In this review, we summarize the recent literatures on one member of the SF2 superfamily, the DEAD-box protein DDX41. After bacterial or viral infection, DNA or cyclic-di-GMP is released to cells. After phosphorylation of Tyr414 by BTK kinase, DDX41 will act as a sensor to recognize the invaders, followed by induction of type I interferons (IFN). After the immune response, DDX41 is degraded by the E3 ligase TRIM21, using Lys9 and Lys115 of DDX41 as the ubiquitination sites. Besides the roles in innate immunity, DDX41 is also related to diseases. An increasing number of both inherited and acquired mutations in DDX41 gene are identified from myelodysplastic syndrome and/or acute myeloid leukemia (MDS/AML) patients. The review focuses on DDX41, as well as its homolog Abstrakt in Drosophila, which is important for survival at all stages throughout the life cycle of the fly.
Agammaglobulinaemia Tyrosine Kinase ; Animals ; Bacterial Infections ; genetics ; immunology ; Cyclic GMP ; analogs & derivatives ; genetics ; immunology ; DEAD-box RNA Helicases ; genetics ; immunology ; Drosophila Proteins ; genetics ; immunology ; Drosophila melanogaster ; Humans ; Leukemia, Myeloid, Acute ; genetics ; immunology ; Mutation ; Myelodysplastic Syndromes ; genetics ; immunology ; Nuclear Proteins ; genetics ; immunology ; Protein-Tyrosine Kinases ; genetics ; immunology ; Virus Diseases ; genetics ; immunology

OBJECTIVETo investigate the clinical and biological characteristics and prognosis of mixed phenotype acute leukemia (MPAL).

METHODSThirty two patients were diagnosed as MPAL by bone marrow examination, immunophenotyping, cytogenetic and molecular assay and were treated with combined chemotherapy regimens for both acute lymphoblastic and acute myeloid leukemia. Two cases were received allogeneic hematopoietic stem cell transplantation (allo-HSCT).

RESULTS(1) The incidence of MPAL in acute leukemias was 2.6%. There were 16 cases (50.0%) of mixed myeloid and B-lymphoid (M/B), 14(43.8%) myeloid and T-lymphoid (M/T), one each (3.1%) of trilineage (M/B/T) and B- and T-lymphoid (B/T) phenotype. (2) The positive rates of CD34 and HLA-DR were 87.5% and 62.5%, respectively. (3) Abnormal karyotypes were detected in 70.0% of 30 MPAL patients, which were structural and numerical abnormalities including t(9;22), 11q23 and complex karyotypes. (4) The total complete remission (CR) rate was 75.0% and the overall survival (OS) and disease-free survival (DFS) at 2 years were 14.8% and 14.2% respectively. The CR rates for M/B and M/T cases were 75.0% and 71.4% respectively. No statistical difference was observed in OS and DFS between M/B and M/T cases.

CONCLUSIONSMPAL is a rare type of acute leukemia with a high heterogeneity. The unfavorable indicators of MPAL may be factors such as abnormal karyotypes, high expression of CD34 and extramedullary infiltration. Combined regimens and more intensive therapy including allo-HSCT might contribute to improving survival.

Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Humans ; Immunophenotyping ; Karyotype ; Leukemia, Biphenotypic, Acute ; classification ; genetics ; immunology ; Leukemia, Myeloid, Acute ; genetics ; immunology ; Male ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; immunology ; Prognosis ; Young Adult

Acute Disease ; Antigens, CD ; analysis ; Biomarkers, Tumor ; analysis ; Chromosome Aberrations ; Diagnosis, Differential ; Humans ; Immunophenotyping ; Leukemia ; classification ; diagnosis ; genetics ; immunology ; Leukemia, Biphenotypic, Acute ; classification ; diagnosis ; genetics ; immunology ; Phenotype

OBJECTIVETo investigate the biologic features of childhood acute leukemia in the northern region of China through a small cohort study in a single center.

METHODSThe medical records of 688 children with acute leukemia (age< or =15 years) who were initially diagnosed at Blood Disease Hospital of Chinese Academy of Medical Sciences from October 2003 to June 2006 were retrospectively studied.

RESULTSFour hundred children were diagnosed as acute lymphoblastic leukemia (ALL), with a peak incidence at ages of 1-4 years. Two hundred and eighteen children were classified into B-cell ALL, and 34 into T-cell ALL. In the 154 patients with cytogenetic data, high hyperdiploidy was presented in 13.0% of patients, low hyperdiploidy in 3.9%, pseudodiploidy in 5.2%, and hypodiploidy in 5.8%. E2A-PBX1 fusion gene was expressed in 3.9% of children with B-cell ALL. Two hundred and twenty-two children were diagnosed as acute myeloid leukemia (AML), with a peak incidence at ages of 10-15 years. AML-M2 was the most common subtype. Acute hybrid leukemia (AHL) was confirmed in 24 children (4.2%), with a median age of 9 years. Seventy-four percent of the children with (AHL) had mainly CD13 and CD33 expression in myeloid antigen integral.

CONCLUSIONSThere are differences in the biologic features of childhood acute leukemia between the northern region of China and other regions and races, which suggests that there might be differences in the pathogenesis of childhood acute leukemia in different environmental exposures.

Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Leukemia, Myeloid, Acute ; epidemiology ; genetics ; immunology ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; epidemiology ; genetics ; immunology ; Retrospective Studies

In order to investigate the inhibition role of anti-Fas hammerhead ribozyme on Fas expression and Fas-mediated apoptosis in CTLL-2 cells (mouse CTL cell line), and to explore a new way for enhancing the ability of T cells against Leukemia in donor lymphocytes infusion, CTLL-2 cells were transfected with pEGFP-RZ596 and pEGFPC1 (mock-transfected) via electroporation. Fas expression on CTLL-2 cells was detected by RT-PCR and Western blot. The killing effect of CTL against WEHI-3 (mouse acute myelomonocytic leukemia cell line) highly expressing FasL in vitro was detected by MTT assay. The caspase-3 proteolytic activity and the apoptosis rate of CTLL-2 cells were detected by means of BD AproAlert Caspase-3 Colorimetric kit and FITC labeled Annexin-V apoptosis detecting kit respectively. The results showed that the anti-Fas ribozyme could be successfully introduced into mouse CTLL-2 cells; Fas expression on the surface of cells transfected with the ribozyme was obviously decreased, in comparison with control and mock-transfected cells; after cocultured with WEHI-3 cells, the viability of CTLL-2 cells transfeced with the ribozyme was significantly increased, as compared with other two groups; caspase-3 activity and apoptosis rate of the ribozyme-transfeced cells were significantly decreased, the killing effect of CTLL-2 transfected with the ribozyme was stronger than that of other groups. It is concluded that anti-Fas ribozyme can remarkably decrease Fas expression on CTLL-2 cells, so as to avoid Fas-mediated apoptosis by Fas ligand on WEHI-3 cells, and to enhance their killing activity against WEHI-3 cells, as a result, the immune escape of acute myelomonocytic leukemia was depressed.
Animals ; Cell Line ; Fas Ligand Protein ; immunology ; Leukemia, Myelomonocytic, Acute ; immunology ; Mice ; RNA, Catalytic ; T-Lymphocytes, Cytotoxic ; cytology ; immunology ; Tumor Cells, Cultured ; Tumor Escape ; genetics ; immunology

OBJECTIVETo construct and express human CD96 gene outer membrane domain (hCD96om) in prokaryotic cells and prepare rabbit polyclonal antibody of hCD96om.

METHODShCD96om was amplified by RT-PCR from the peripheral blood of patients with acute myeloid leukemia and inserted into prokaryotic expression vector pET32a(+) to construct the recombinant plasmid pET32-CD96. The expression of hCD96om was induced by IPTG in BL21(DE3) cells, and the expression product was identified by Western blotting. The anti-hCD96 polyclonal antibody was prepared by immunization of rabbits with the fusion protein. The specificity of anti-hCD96 antibody was determined by Western blotting.

RESULTShCD96om protein was expressed in E.coli BL21(DE3) cells in the form of inclusion body, with a relative molecular mass around 37 kD. Western blotting showed a specific reaction of the prepared antiserum with the 70 kD protein extracted from human leukemia cell line HL-60 cells and with the 37 kD hCD96om fusion protein.

CONCLUSIONThe CD96 gene of human has been successfully cloned and expressed in BL21(DE3) cells, and its rabbit polyclonal antibody has been obtained.

Animals ; Antibodies ; immunology ; metabolism ; Antigens, CD ; biosynthesis ; genetics ; immunology ; Base Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Humans ; Immune Sera ; biosynthesis ; Immunization ; Leukemia, Myeloid, Acute ; immunology ; Molecular Sequence Data ; Neoplastic Stem Cells ; immunology ; Rabbits ; Recombinant Proteins ; biosynthesis ; genetics ; immunology