Clonal Analysis of B-Cell Leukemias and Lymphomas using the Polymerase Chain Reaction for the Third Complementarity Determining Region of the IgH Gene: A Study of 75 Cases from Nagasaki Japan

Abstract

Using semi-nested polymerase chain reaction (PCR), we examined 75 Japanese cases of hematologic malignancies with B-cell antigens including 25 common acute lymphoblastic leukemia (ALL), 13 chronic lymphocytic leukemia (CLL), 28 B-cell malignant lym-phoma(B-ML), 2 hairy cell leukemia (HCL), 7 acute myelogenous leukemia with B-cell antigens (AML-B), and 23 controls. When amplified products were analysed by a standard polyacrylamide gel electrophoresis, the sensitivity for detection of clonal IgH rearrangements in each group of ALL, CLL, B-ML, HCL, and AML-B was 88%, 92,3%, 71.4%,100%, and 57.1%, respectively, with an overall sensitivity of 80.0%. There were no false positive results in any of the control sampIes. Single strand conformation polymorphism (SSCP) analysis of the amplified products gave rise. to a much greater sensitivity, up to 84% overall. The false negative samples were mainly encountered in B-ML with SmIgG and non-Ig, suggesting miss-annealing between the primers used and the template DNA because of somatic hyper-mutation of IgH genes in such clones. This indicates that PCR analysis is very useful in detecting the clonal IgH rearrangements in B-cell malignancies, especially in ALL and CLL, but not in B-ML corresponding to neoplasms originating from pre-germinal center naive B-cells.

Key Words:

• PCR
• IgH gene
• CDR3
• clonality
• B-Cells