A novel four-color PCR assay to assess T-cell receptor gamma gene rearrangements in lymphoproliferative lesions

We describe a novel 4-color polymerase chain reaction (PCA) assay combined with GeneScan analysis to assess fort T-cell receptor gamma chain gene (TCR gamma) rearrangements and evaluate its usefulness in 86 lymphoproliferative lesions. In this assay, each variable region (V-gamma) family primer is 5 ' end-labeled with a different fluorescent dye, allowing determination of t he V-gamma family involved in each TCRgamma rearrangement PCR products were analyzed by capillary electrophoresis. We detected clonal TCRgamma rearran gements in 60 (98%) of 61 T-cell lymphomas, 2 (15%) of 13 B-cell lymphomas, and 3 (25%) of 12 reactive lesions. These results compared favorably with conventional PCR methods using denaturing gradient gel electrophoresis, whi ch revealed clonal TCRgamma rearrangements in 37 (90%) of 41 T-cell lymphom as, 1 (25%) of 4 B-cell lymphomas, and 2 (25%) of 8 reactive lesions. This 4-color PCR assay is at least equivalent to conventional PCR methods and is convenient, allows accurate size determination of TCRgamma rearrangements, and identifies the specific V-gamma family involved, providing more specif ic information about TCRgamma rearrangement.