RESUMO
Phenotypic markers of leukemic cells from 29 children with acute leukemia were examined. Of these cases, six were negative for myeloperoxidase and did not react with lineage-associated or mature lineage-associated monoclonal antibodies. Then, we analyzed the configuration of both immunoglobulin (heavy chain and kappa chain) and T-cell receptor (?, ?, ?) genes in these six cases. All cases had rearrangement of IgH were suggestive of B-lymphoid origin of these leukemic cells. Two cases without CD10 antigen had no rearrangement of kappa chain, one with retention of the germline configuration of TCR ?, ?. ?, the other with retention of the germline of TCR ? gene. In the cases with CD10 antigen, two cases showed kappa chain deletion, the alteration of TCR genes (rearrangements or deletions )was shown to occur frequently. These findings may implicate that the gene rearrange ments forming functional IgH gene in leukemic cells with CD10 antigen, induce the alteration of IgL and TCR genes.