Rearrangement of T-cell δ locus in lymphoproliferative disorders

Abstract

Studies of lymphoproliferative disorders using immunoglobulin and T-cell receptor genes have contributed to our understanding of clonality and lineages of these disorders. In this study, we examined the rearrangement of the recently discovered T-cell δ chain genes in a variety of lymphoproliferative diseases. We show here that six of 14 T-cell lymphomas and five of 23 B-cell lymphomas or B-cell leukemia cell lines have rearranged the δ loci, while two of two hyperimmune reactions retain germline configuration within these genes. Seven of ten cases of AILD were rearranged, and Lennert's lymphoma, which has been previously described as a T-cell malignancy, also contains rearrangements in the δ chain genes (three of five). Large cell anaplastic lymphomas positive for the activation antigen CD 30 also contain rearrangement in about one-half (five of 11) of the tumors examined. Two of seven of the Hodgkin's lymphomas studied contained a rearrangement for this gene. This study indicates that this newly identified T-cell δ gene is useful in evaluating clonality but is not lineage specific. However, with only one exception (in 28 rearrangements), this gene rearranges in tumors with γ and β chain gene rearrangements, indicating that when used in conjunction with the other TcR genes, δ rearrangement may also be useful in evaluating lineages.