ABSTRACT
About 80% to 90% of females are informative for X-inactivation/methylation analysis with the probe M27 beta, which would therefore seem attractive in assessing clonality in hematologic cell populations. Eighteen acute lymphoid or myeloid leukemias, three chronic lymphocytic leukemias, and three chronic myelogenous leukemias as well as 12 malignant non-Hodgkin's lymphomas mostly showed extremely skewed clonal X inactivation (median allelic cleavage ratio [ACR] of unmethylated/inactive M27 beta alleles was 50, range 1 to 100) or hypermethylation of both alleles. Two lymphomas showed random M27 beta X inactivation but clonal antigen-receptor gene rearrangements. In normal peripheral blood leukocytes from 105 healthy females aged 2 to 96 years, the median ACR was 2 (range 1 to 100). Thus, it was significantly lower than in the leukemias (P = .0001, Mann-Whitney test), but extremely skewed patterns (ACR > 10.8, ie, > 80th percentile) were seen not only in the leukemias but also in 21/105 samples (20%) of normal leukocytes, and significantly more frequent in a population of elderly women (aged 75 to 96 years) compared with healthy children (aged 2 to 8 years) and younger women (aged 20 to 58 years) (P = .00125; chi 2 test). We conclude that in a population of cells derived from the hematopoietic system where clonality is uncertain, skewed M27 beta patterns are not reliable indicators for the presence of a clonal neoplastic disorder. The basis for severe X-inactivation skewing is unclear at present, but this finding raises interesting questions regarding the composition of the hematopoietic stem cell pool.
Subject(s)
Aging/physiology , Hematopoiesis , Leukocytes/physiology , X Chromosome , Acute Disease , Adult , Aged , Aged, 80 and over , Base Sequence , Blotting, Southern , Child , Child, Preschool , Chronic Disease , Cloning, Molecular , DNA Primers , DNA Probes , Female , Humans , Leukemia/blood , Leukemia/genetics , Lymphoma, Non-Hodgkin/blood , Lymphoma, Non-Hodgkin/genetics , Methylation , Middle Aged , Molecular Sequence Data , Polymerase Chain Reaction , Polymorphism, Genetic , Reference Values , Restriction MappingABSTRACT
A novel association, Epstein-Barr virus-positive Ki-1+/CD30+ anaplastic large cell non-Hodgkin's lymphoma of B-cell phenotype in immunosuppressed renal transplant recipients is reported. Case 1 involved an aggressive clinical evolution, whereas case 2 followed a more "benign" clinical course. Both lymphomas were Epstein-Barr virus-positive as assessed by in situ hybridization, Southern blot, polymerase chain reaction, and immunohistochemical analysis. Both lymphomas contained a single clonal Epstein-Barr virus terminal-repeat fragment. In case 1, clonality was confirmed by the detection of bi-allelic immunoglobulin (Ig) heavy chain gene rearrangement. Case 2 showed germline Ig genes at presentation and oligoclonal Ig heavy chain gene rearrangements at relapse. These results are consistent with the notion that anaplastic large cell lymphoma might arise in a B cell transformed by Epstein-Barr virus at a very early stage, before Ig gene rearrangement. The latter may occur later in the course of clonal evolution, thus permitting investigators to trace intermediate and late stages within a process of multistep lymphomagenesis and/or tumor progression.
Subject(s)
Herpesvirus 4, Human/isolation & purification , Kidney Transplantation , Lymphoma, Large B-Cell, Diffuse/microbiology , Adolescent , Adult , Antigens, CD/analysis , Antigens, Neoplasm/analysis , Blotting, Southern , DNA Probes , DNA, Neoplasm/analysis , DNA, Viral/analysis , Herpesvirus 4, Human/genetics , Humans , Immunohistochemistry , Ki-1 Antigen , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/immunology , Male , Nucleic Acid Hybridization , Polymerase Chain Reaction , Postoperative Complications/immunology , Postoperative Complications/microbiologyABSTRACT
13 cases of childhood acute lymphoblastic leukaemia (ALL) were studied combining cell surface marker analysis with immunogenotyping by Southern blot hybridisation with a panel of antigen receptor gene probes. The immunophenotypes were unequivocal: 7 patients had B-phenotype and 6 patients T-phenotype ALL. In several patients immunogenotypes were not fully consistent with the respective phenotypes. For example, 2 B-cell precursor ALL had rearranged TCR beta chain genes and 2 T-ALL rearrangement of Ig heavy-chain genes. All cases showed clonal rearrangement or deletions within the TCR delta gene locus. TCR delta gene rearrangements might, therefore, serve as markers of clonality but not of B- or T-lineage in immature lymphoid neoplasms. We conclude that in current diagnostic practice immunogenotyping is a supplement rather than an alternative to immunophenotyping by surface marker analysis.
Subject(s)
Bacterial Proteins , Burkitt Lymphoma/diagnosis , Gene Rearrangement , Genotype , Leukemia-Lymphoma, Adult T-Cell/diagnosis , Receptors, Antigen, T-Cell/genetics , Adolescent , Burkitt Lymphoma/genetics , Child , Child, Preschool , DNA Probes , Deoxyribonuclease EcoRI , Deoxyribonuclease HindIII , Deoxyribonucleases, Type II Site-Specific , Gene Rearrangement, T-Lymphocyte , Gene Rearrangement, beta-Chain T-Cell Antigen Receptor , Humans , Immunoglobulin Heavy Chains/genetics , Immunophenotyping , Infant , Leukemia-Lymphoma, Adult T-Cell/genetics , Nucleic Acid Hybridization , Polymorphism, Restriction Fragment LengthSubject(s)
Antibodies, Anti-Idiotypic/analysis , Immunoglobulin G , Adsorption , Amino Acid Sequence , Animals , Chromatography, Gel , Chromatography, Paper , Electrophoresis , Electrophoresis, Paper , Humans , Immunization , Immunodiffusion , Immunoelectrophoresis , Immunoglobulin Fab Fragments/analysis , Immunoglobulin Fragments/analysis , Isoelectric Focusing , Papain , Pepsin A , Peptides/analysis , Rabbits/immunology , Sheep/immunology , Spectrophotometry, UltravioletABSTRACT
An improved method for the isolation of normal immunoglobulin E is described. The method is based on the use of an immunoadsorbent formed by the mechanical entrapment of antibodies against a myeloma immunoglobulin E into a lattice of a highly cross-linked macroporous polyacrylamide gel. Normal immunoglobulin E was isolated from an immunoglobulin E-rich serum pool as well as from an individual healthy donor. The isolated immunoglobulin E was contaminated with about 20% of immunoglobulin G. An antiserum against normal immunoglobulin E was prepared by immunizing rabbits with the isolated immunoglobulin E.
