Alternative expression of TCRζ related genes in patients with chronic myeloid leukemia

Abstract

A previous study has demonstrated a significant decrease in the TCRζ gene expression level in chronic myeloid leukemia (CML); thus, we further investigated the expression of TCRζ-regulating factors, the distribution of the TCRζ 3' untranslated region (3'-UTR) splice variants, and the expression level and correlation of the alternative splicing factor/splicing factor 2 (ASF/SF-2), FcεRIγ and ZAP-70 genes. TCRζ 3'-UTR splice variants were identified in peripheral blood mononuclear cells (PBMCs) from 14 healthy individuals, 40 patients with CML and 22 patients with CML in complete remission (CML-CR) by RT-PCR. The expression level of the TCRζ, FcεRIγ, ASF/SF-2 and ZAP-70 genes was analyzed by real-time quantitative PCR. While the expression of TCRζ gene in the CML group was significantly lower than that in the healthy individual and CML-CR groups, a significantly higher expression of the FceRIγ and ASF/SF-2 genes was found in the CML group. Two types of splicing forms were detected in all of the healthy individual CML-CR cases: wild type (WT) TCRζ 3'-UTR and alternatively splieced (AS) TCRζ 3'-UTR which have been alternatively splieced in the WT TCRζ 3'-UTR . However, 35% of the CML cases contained only the wild type TCRζ 3'-UTR isoform. Based on the TCRζ 3'-UTR isoform expression characteristic, we divided the patients with CML into two subgroups: the WT+AS- CML group, containing patients that express only the wild type TCRζ 3'-UTR, and the WT+AS+ CML group, which contained patients that expressed two TCRζ 3'-UTR isoforms. A significantly different ASF/SF-2 and FcεRIγ gene expression pattern was found between the WT+AS- and WT+AS+CML groups. We concluded that defective TCRζ expression may be characterized in the WT+AS-and WT+AS+CML subgroups by the different gene expression pattern. The overexpression of ASF/SF2, which alternatively splices the TCRζ 3’-UTR, is thought to participate in feedback regulation. The characteristics of TCRζ 3'-UTR alternative splicing may be a novel immunological marker for the evaluation of the CML immune status.

Enhancement of the TCRζ Expression, Polyclonal Expansion, and Activation of T Cells from Patients with Acute Myeloid Leukemia After IL-2, IL-7, and IL-12 Induction

“…Such deficiency in CD3 gene expression levels might be, at least, a part of the reason for the reduction in T cell activation in AML. Similar findings were also reported in CML, CLL, and lymphomas (Huang et al, 2012;Zha et al, 2012b;Liao et al, 2014). Therefore, enhancing CD3 expression may reactive the T cell activation functions and reverse the immunodeficiency in leukemia patients.…”

“…Therefore, enhancing CD3 expression may reactive the T cell activation functions and reverse the immunodeficiency in leukemia patients. Enhancement in TCRz (CD3z), which is crucial for TCR signaling functions, because it provides 6 of 10 immunoreceptor tyrosine-based activation motifs for the TCR-CD3 complex (Call and Wucherpfennig, 2005;Li, 2008;Zha et al, 2012a), was reported by different methods, including cytokine induction and TCRz transfer in T cells of CML patients (Chen et al, 2009;Zha et al, 2012b). A previous study showed that IL-2 could enhance the TCRf level, but it could not completely recover the TCRf level in T cells in CML patients (Chen et al, 2009).…”

“…T cells from patients with leukemia are functionally impaired, and this is related to a decrease in the TCRz chain expression (Chen et al, 2000;Fischer et al, 2005;Li, 2008;Chen et al, 2011). Recently, we have reported significantly lower expression of TCRf in patients with AML and CML, and increasing TCRz expression by gene transfer enhances the activation and cytotoxicity of T cells from patients with CML (Chen et al, 2009;Zha et al, 2012aZha et al, , 2012b. However, there are few data characterizing TCRz upregulation and the T cell activation and proliferation induced by different methods such as gene transfer and cytokine induction in T cells from AML.…”

The TCR γδ Repertoire and Relative Gene Expression Characteristics of T-ALL Cases with Biclonal Malignant Vδ1 and Vδ2 T Cells

“…Specific amplification of the PCR products was confirmed by melting curve analysis. The data are presented as the relative expression of the genes of interest compared with the internal control gene as determined by the 2( -DCT ) method (Zha et al, 2012;Shi et al, 2013).…”

Chronic Myelocytic Leukemia (CML) Patient-Derived Dendritic Cells Transfected with Autologous Total RNA Induces CML-Specific Cytotoxicity

“…CML patients have significantly lower numbers of circulating myeloid and plasmacytoid dendritic cells (pDCs) compared with healthy volunteers [8,9]. Bcr/abl1-presenting DCs have been detected in the peripheral blood of CML patients, suggesting that CML-derived DCs may contribute to anti-leukemic immunity [10,11]. Bcr/abl1-presenting DCs can be generated from peripheral blood mononuclear cells (PBMCs) or CD34c progenitor cells of CML patients, and have been shown to have the capacity to capture, process and present bcr/abl1 antigen [5,12].…”