Heterogeneity of V52 TCR 8 Gene Rearrangements in Acute Myeloid Leukemia

Abstract

In a previous study, we described the occurrence of T-cell receptor (TCR)δ gene rearrangements in 9/100 acute myeloid leukemia (AML) cases. In this study, we further characterized these rearrangements by Southern Blot hybridization using a Vδ2 specific probe and polymerase chain reaction (PCR). Southern Blot analysis revealed that rearrangements involved the Vδ2 gene segment in four patients. Interestingly the restriction fragments detected by the Vδ2 probe differed markedly in size. PCR analysis revealed a complete Vδ2(Dn)Jδ1 gene rearrangement, an incomplete Vδ2Dδ3 rearrangement and a large amplification product, which cannot be explained with normal VDJ recombinatorial processes, in one case each. Furthermore although Vδ2 and Jδ1 were rearranged, no comigration of rearranged fragments was observed and no PCR product was obtained in one case.

Obtained results in AML differ from findings in acute lymphoblastic leukemia (ALL) of B-cell lineage, where a more homogeneous pattern of rearrangements has been described. This heterogeneity might be related to the illegitimate occurrence of TCRδ gene rearrangements in AML.

Key Words:

• Acute myeloid leukemia
• T-cell recetor delta gene
• gene rearrangement