[Antigen receptor gene analysis in lymphoid malignancies--a study using the polymerase chain reaction]

A leukemia line KOPN30bi was established from a patient of acute lymphoblastic leukemia with Philadelphia chromosome. The clonal rearrangement of the immunoglobulin heavy chain gene was identical between KOPN30bi and the predominant clone in the fresh sample (S1) from which KOPN30bi was established, indicating that they are of the same clonal origin. The study of the T cell receptor (TCR) genes including TCR beta, gamma, delta loci showed none of these loci was identical between KOPN30bi and S1. The result of the TCR delta region analysis which was rearranged on one of the alleles in KOPN30bi and was deleted on both alleles in S1, however, indicated KOPN30bi was not a derivative of S1. Polymerase chain reaction, using oligonucleotide probe corresponding to the N region sequence of V gamma-J gamma juncture of KOPN30bi, indicated that only one % of the blast cells in S1 corresponded to KOPN30bi. These studies indicated that the predominant clone in the fresh sample, although it occupied more than 99% of the blasts, did not represent the characteristics of the target cell for leukemogenesis, and furthermore that the leukemogenic molecular mechanisms such as P190 type BCR/ABL translocation are not enough to freeze the differentiation of the target cell.