Clinical application of TRBC1/TRBC2 detection by flow cytometry in assessing clonality of T-cell lymphoma
10.3760/cma.j.cn114452-20250305-00131
- VernacularTitle:流式细胞术检测TRBC1/TRBC2在评估T细胞淋巴瘤克隆性的临床应用
- Author:
Xueyan CAO
1
;
Jiwei LI
;
Dongyao YAN
;
Menghan LI
;
Zhaoming LI
;
Baohong YUE
Author Information
1. 郑州大学基础医学院，郑州 450000
- Publication Type:Journal Article
- Keywords:
Lymphoma;
T-cell lymphoma;
Flow cytometry;
T Cell receptor beta constant region;
Clonality
- From:
Chinese Journal of Laboratory Medicine
2025;48(8):1055-1062
- CountryChina
- Language:Chinese
-
Abstract:
Objective:Explore the clinical utility of TRBC1/TRBC2 dual staining by flow cytometry in determining clonality in T-cell lymphomas.Methods:This is a retrospective case-control study. A total of 40 patients with T-cell lymphoma involving bone marrow from the First Affiliated Hospital of Zhengzhou University were enrolled between December 10, 2024 and March 5, 2025. This cohort included 30 cases of mature T-cell lymphoma, 16 males and 14 females, age 62 (54, 71)years, and 10 cases of T-lymphoblastic leukemia/lymphoma[age 11(7, 33)years ]. Additionally, 30 control subjects without T-cell lymphoproliferative disorders were included (17 males and 13 females[age 55(47, 67)years]. Multiparameter flow cytometry (FCM) was performed to analyze TRBC1 and TRBC2 expression patterns in different αβ-T cell subsets within bone marrow samples. Neoplastic T lymphocytes were identified and gated based on immunophenotypic markers (CD3, CD2, CD5, CD7, etc.), followed by characterization of their TRBC1 and TRBC2 expression profiles. Statistical comparisons among multiple groups were conducted using the Kruskal-Wallis test, while the Wilcoxon rank-sum test was employed for pairwise comparisons.Results:In the mature T-cell lymphoma group, 66.7% (21/30) of cases demonstrated monotypic expression of either TRBC1 or TRBC2. Despite the rest 33.3% (9/30) of cases with surface CD3 negativity showed complete loss of both surface and intracellular TRBC1 and TRBC2 (dual-negative), TCR gene rearrangement positivity confirmed their biologically monoclonal proliferation. In contrast, control group αβ-T cells and their subsets exhibited polytypic TRBC1 and TRBC2 expression. Compared to control αβ-T cells, mature T-cell lymphomas showed statistically significant differences in TRBC1 ( U=270.00, P<0.05) and TRBC2 ( U=300.00, P<0.05) distribution. Within control group T-cell subsets, using a threshold of>85% TRBC1-or TRBC2-positive cells, T-cell clones of uncertain significance (T-CUS) were detected in 23% (7/30) of controls, in which 12 clonal proliferations were totally found. These T-CUS clones were significantly associated with CD57+T cells, suggesting a possible link to immunosenescence or chronic antigen stimulation. Among T-ALL/LBL patients, 2 cases showed intracellular TRBC monotypic expression, while 8 cases exhibited dual-negative intracellular TRBC expression, which aids in differentiating T-ALL/LBL from normal thymocytes (which usually display polytypic TRBC expression). Conclusion:Multiparameter flow cytometry (FCM) combined with TRBC1/TRBC2 dual staining can effectively distinguish neoplastic T cells from normal T lymphocyte populations. This approach serves as a crucial determinant for assessing T-cell clonality and can definitively identify TRBC subtypes (TRBC1 or TRBC2).
