THE MAJORITY OF T-LYMPHOCYTES ARE POLYCLONAL DURING THE CHRONIC PHASEOF CHRONIC MYELOGENOUS LEUKEMIA

To clarify the extent of cell lineage involvement in chronic myelogeno us leukemia (CML), we investigated the bcr gene rearrangement and clon ality using the X-chromosome-linked restriction fragment length polymo rphism (RFLP) methylation method in T lymphocytes and granulocytes. We examined the granulocyte and T-cell fractions from the peripheral blo od of seven female patients with CML during the chronic phase patients were heterozygous for RFLPs at the phosphoglycerate kinase (PGK) or t he hypoxanthine phosphoribosyltransferase (HPRT) gene. RFLP-methylatio n analysis of granulocytes demonstrated a monoclonal pattern in six of the seven patients and a rearranged bcr gene in all seven patients. I n contrast, T lymphocytes exhibited a polyclonal pattern in six cases; in one case, a faint band was observed following methyl-sensitive enz yme cleavage. The bcr gene analysis in T lymphocytes showed the germli ne in every case. Our results indicate that the majority of T lymphocy tes are polyclonal during the chronic phase of CML and confirm previou s reports based on glucose-6-phosphate dehydrogenase, cytogenetic, and bcr rearrangement analyses.