Frequency analysis of TRBV subfamily sjTRECs to characterize T-cell reconstitution in acute leukemia patients after allogeneic hematopoietic stem cell transplantation

• Published in: Journal of hematology and oncology Vol. 4; no. 1; p. 19
• Main Authors: Wu, Xiuli, Zhu, Kanger, Du, Xin, Chen, Shaohua, Yang, Lijian, Wu, Jufeng, Liu, Qifa, Li, Yangqiu
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 23.04.2011; BioMed Central; BMC
• Subjects: Acute Disease; Acute leukemia; Adolescent; Adult; Antigen receptors, T cell; Antineoplastic Agents - therapeutic use; Care and treatment; Flow Cytometry; Gene Rearrangement, T-Lymphocyte; Genetic aspects; Graft vs Host Disease - genetics; Graft vs Host Disease - immunology; Hematopoietic Stem Cell Transplantation - methods; Hematopoietic stem cells; Humans; Leukemia - genetics; Leukemia - immunology; Leukemia - surgery; Leukemia, Myeloid - genetics; Leukemia, Myeloid - immunology; Leukemia, Myeloid - surgery; Leukocytes, Mononuclear - immunology; Leukocytes, Mononuclear - metabolism; Middle Aged; Physiological aspects; Precursor Cell Lymphoblastic Leukemia-Lymphoma - genetics; Precursor Cell Lymphoblastic Leukemia-Lymphoma - immunology; Precursor Cell Lymphoblastic Leukemia-Lymphoma - surgery; Receptors; Receptors, Antigen, T-Cell, alpha-beta - genetics; Reverse Transcriptase Polymerase Chain Reaction; T cells; T-Lymphocytes - immunology; T-Lymphocytes - metabolism; Thymus Gland - immunology; Thymus Gland - metabolism; Time Factors; Transplantation; Transplantation Conditioning - methods; Transplantation, Homologous; Vidarabine - analogs & derivatives; Vidarabine - therapeutic use; Young Adult; China
• ISSN: 1756-8722; 1756-8722
• DOI: 10.1186/1756-8722-4-19

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) leads to a prolonged state of immunodeficiency and requires reconstitution of normal T-cell immunity. Signal joint T-cell receptor excision DNA circles (sjTRECs) are markers of developmental proximity to the thymus that have been used to evaluate thymic function related to T-cell immune reconstitution after HSCT. To assess the proliferative history in different T-cell receptor beta variable region (TRBV) subfamilies of T cells after HSCT, expansion of TRBV subfamily-naive T cells was determined by analysis of a series of TRBV-BD1 sjTRECs. sjTRECs levels were detected by real-time quantitative polymerase chain reaction (PCR) in peripheral blood mononuclear cells (PBMCs) from 43 Chinese acute leukemia patients who underwent allo-HSCT. Twenty-three TRBV-BD1 sjTRECs were amplified by semi-nested PCR. Sixteen age-matched healthy volunteers served as normal controls. sjTRECs levels were low or undetectable in the first 6 weeks after allo-HSCT and increased after 8 weeks post HSCT; however, sjTRECs levels at week 20 post-HSCT were still less than normal controls. Frequencies of TRBV subfamily sjTRECs in PBMCs from recipients at week 8 post-HSCT (29.17 ± 20.97%) or at week 16 post-HSCT (38.33 ± 9.03%) were significantly lower than those in donors (47.92 ± 13.82%) or recipients at pre-HSCT (45.83 ± 14.03%). However, frequencies of TRBV subfamily sjTRECs in recipients at week 30 post-HSCT (42.71 ± 21.62%) were similar to those in donors and recipients at pre-HSCT. sjTRECs levels in donors had a positive linear correlation with sjTRECs levels in recipients within 8-12 weeks post-HSCT. Patients with acute graft-versus-host disease (GVHD) or chronic GVHD had profoundly reduced TRECs levels during the first year post-HSCT. Frequencies of BV22-BD1 sjTRECs and BV23-BD1 sjTRECs in patients with GVHD were significantly lower than those in recipients at pre-HSCT, and the frequencies of BV22-BD1 sjTRECs in patients with GVHD were significantly lower than those in donors. Reconstitution of thymic output function resulted in a period of immunodeficiency, with low or undetectable TRECs after transplantation, although fludarabine-based dose-reduced conditioning regimens were used. GVHD could affect reconstitution of thymic output function and reduce sjTRECs levels and frequencies of TRBV-BD1 sjTRECs. Low frequency of BV22-BD1 and BV23-BD1 sjTRECs might be associated with GVHD.