Detection of clonal T-cell receptor gamma gene rearrangements using fluorescent-based PCR and automated high-resolution capillary electrophoresis.
BACKGROUND
Analysis of T-cell receptor gamma (TCR gamma) gene rearrangements by PCR is a powerful tool for detecting clonal T-cell populations for the diagnosis of lymphoid neoplasms. We report a method for TCR gamma PCR analysis using capillary electrophoresis (CE).


RESULTS
To define the threshold for identification of a predominant monoclonal population within a polyclonal background, we developed a novel objective parameter of the peak height ratio (Rn) of the peak of interest and the average of the two immediate flanking peaks. After evaluation of monoclonal, reactive, and normal T-cell populations, an Rn of 3.0 or greater was determined to be consistent with a monoclonal population, whereas an Rn between 1.9 and 3.0 was considered an intermediate range. This CE method was compared with the standard denaturing gradient gel electrophoresis (DGGE) method using previously evaluated clinical specimens. Eleven of 12 clinical specimens (92%) with a definitive diagnosis of T-cell lymphoma were monoclonal by CE, with 100% concordance with the DGGE method. Of nine specimens morphologically suspicious for T-cell lymphoma, five specimens were positive by CE analysis compared with four specimens by DGGE. In addition, 14 specimens for staging from patients with known T-cell lymphoma were studied using both the CE and DGGE methods, with a concordance of 86%.


CONCLUSIONS
CE is a powerful and efficient method for analysis of clonality by TCR gamma PCR.
Luo
V
V
Molecular Pathology Laboratory, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104-4283, USA.
Lessin
S R
SR
Wilson
R B
RB
Rennert
H
H
Tozer
C
C
Benoit
B
B
Leonard
D G
DG
D001706:Biopsy; D002999:Clone Cells; D017931:DNA Primers; D004273:DNA, Neoplasm / Q000032:analysis; D019075:Electrophoresis, Capillary; D004591:Electrophoresis, Polyacrylamide Gel; D005453:Fluorescence; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor / Q000235:genetics*; D019675:Genes, T-Cell Receptor gamma / Q000235:genetics*; D006801:Humans; D016399:Lymphoma, T-Cell / Q000235:genetics / Q000473:pathology; D016410:Lymphoma, T-Cell, Cutaneous / Q000235:genetics* / Q000473:pathology; D016612:Paraffin Embedding; D016133:Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology
D017931:DNA Primers; D004273:DNA, Neoplasm