Granulocyte colony-stimulating factor affects the distribution and clonality of TRGV and TRDV repertoire of T cells and graft-versus-host disease

Can GCSF-stimulated donor lymphocyte infusions improve outcomes for relapsed disease following allogeneic hematopoietic cell transplantation? A systematic review and meta-analysis

Donor lymphocyte infusions (DLI) can produce graft-versus tumor effects to treat relapse after allogeneic hematopoietic cell transplantation, however, durable responses remain uncommon. A systematic review and meta-analysis are needed to clarify whether DLI collected after stimulation with granulocyte colony-stimulating factor (GCSF; G-DLI) can improve clinical outcomes. Sixteen studies (4 controlled) involving 585 patients were identified in a systematic search up to 17 September 2020. A meta-analysis demonstrated no significant difference in the risk of all-cause mortality (RR: 0.94, 95% CI 0.52-1.68, p = 0.82; n = 3 studies) or relapse-related mortality (RR: 0.72, 0.44-1.18, p = 0.19; n = 3 studies) between G-DLI and conventional DLI (C-DLI) groups. G-DLI products had similar mean CD3+ cells compared to C-DLI products, but median CD34+ cells/kg were increased. No improvement in disease progression, complete response rates, or risk of developing GVHD was observed with G-DLI, however, greater non-relapse mortality was observed compared to C-DLI. Alternative approaches to enhancing graft-versus-tumor effects are needed.

Gamma delta T-cell reconstitution after allogeneic HCT: A platform for cell therapy

Allogeneic Hematopoietic stem cell transplantation (allo-HCT) is a curative platform for several hematological diseases. Despite its therapeutic benefits, the profound immunodeficiency associated with the transplant procedure remains a major challenge that renders patients vulnerable to several complications. Today, It is well established that a rapid and efficient immune reconstitution, particularly of the T cell compartment is pivotal to both a short-term and a long-term favorable outcome. T cells expressing a TCR heterodimer comprised of gamma (γ) and delta (δ) chains have received particular attention in allo-HCT setting, as a large body of evidence has indicated that γδ T cells can exert favorable potent anti-tumor effects without inducing severe graft versus host disease (GVHD). However, despite their potential role in allo-HCT, studies investigating their detailed reconstitution in patients after allo-HCT are scarce. In this review we aim to shed lights on the current literature and understanding of γδ T cell reconstitution kinetics as well as the different transplant-related factors that may influence γδ reconstitution in allo-HCT. Furthermore, we will present data from available reports supporting a role of γδ cells and their subsets in patient outcome. Finally, we discuss the current and future strategies to develop γδ cell-based therapies to exploit the full immunotherapeutic potential of γδ cells in HCT setting.

High TRGV 9 Subfamily Expression Marks an Improved Overall Survival in Patients With Acute Myeloid Leukemia

Background

Heterogeneous T cells in acute myeloid leukemia (AML) have the combinatorial variety generated by different T cell receptors (TCRs). γδ T cells are a distinct subgroup of T cells containing TCRγ (TRGV) and TCRδ (TRDV) subfamilies with diverse structural and functional heterogeneity. Our previous study showed that clonally expanded TRDV T cells might benefit the immune response directed against AML. However, the features of the TRGV repertoire in AML remain unknown. To fully characterize the features of γδ T cells, we analyzed the distribution and clonality of TRGV I-III subfamilies (TRGV II is also termed TRVG 9), the proportions of γδ T cell subsets, and their effects on the overall survival (OS) of patients with AML.

Methods

In this study, the complementarity-determining region 3 (CDR3) size of TRGV subfamilies in γδ T cells of peripheral blood (PB) from de novo AML patients were analyzed by Genescan analysis. Expression levels of TRGV subfamilies were performed by real-time quantitative PCR. The proportions of total γδ T cells and their Vγ9⁺ Vδ2⁺ T cells subsets were detected by multicolor flow cytometry assay. We further compared the correlation among the TRGV gene expression levels, the proportion of Vγ9⁺ Vδ2⁺ T cells, and OS in AML.

Results

We first found that the distribution pattern and clonality of TRGV subfamilies were changed. The expression frequencies and gene expression levels of three TRGV subfamilies in AML samples were significantly lower than those in healthy individuals (HIs). Compared with HIs, the proportions of total γδ T cells and Vγ9⁺ Vδ2⁺ T cells were also significantly decreased in patients with AML. In addition, patients with AML who had higher expression levels of the TRGV gene and higher proportion of Vγ9⁺ Vδ2⁺ T cells showed better OS than their counterparts. Furthermore, high expression levels of TRGV 9 and proportion of Vγ9⁺ Vδ2⁺ T cells were identified as independent protective factors for complete remission in patients with AML.

Conclusions

The restriction of TRGV usage might be related to the preference of usage of γδ T cells. Higher expression of TRGV subfamilies might be associated with better OS in AML. Higher TRGV 9 expression and increased Vγ9⁺ Vδ2⁺ T cells subfamilies might indicate a better prognosis in patients with AML.

Characterizing the BCR repertoire during lymphocyte reduction and recovery mediated by cyclophosphamide and granulocyte-macrophage colony-stimulating factor

Leukopenia is a common manifestation of many diseases, including global outbreak SAS-CoV-2 infection. Granulocyte-macrophage colony-stimulating factor (GM -CSF) has been proved to be effective in promoting lymphocyte regeneration, but adverse immunological effects have also emerged. This study aim to investigate the effect of GM -CSF on BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration. Cyclophosphamide (CTX) and GM -CSF were used to inhibit and stimulate bone marrow hematopoiesis, respectively. High throughput sequencing was applied to detect the characteristics of BCR CDR3 repertoire in controls, CTX group and GM -CSF group. The white blood cells (WBCs) were quickly reduced (P < 0.05) with lymphocytes decreasing causing by CTX, and the WBCs and lymphocytes returned to the level of controls after GM -CSF treatment. The diversity of BCR heavy chain CDR3 repertoire was also significantly decreased in CTX group. Although there is still a big gap from the controls, the diversity was picked up after GM -CSF treatment. The expression of IGHD01-01, IGHD02-14 and IGHJ04-01 with high-frequency usage regularly and significantly changed in three groups, and many genes with low-frequency usage lost in CTX group and did not reappear in GM -CSF group. Moreover, two shared sequences and accounted for the highest proportion in GM -CSF group have been detected in animal model of chronic lymphocytic leukemia. These results revealed that GM -CSF can partially restore changes in the BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration, but it may also lead to rearrangement, proliferation and activation of abnormal B cells, which can provide a basis for further study on the adverse immunological effects and mechanism of GM -CSF treatment.

γδ T Cells for Leukemia Immunotherapy: New and Expanding Trends

Recently, many discoveries have elucidated the cellular and molecular diversity in the leukemic microenvironment and improved our knowledge regarding their complex nature. This has allowed the development of new therapeutic strategies against leukemia. Advances in biotechnology and the current understanding of T cell-engineering have led to new approaches in this fight, thus improving cell-mediated immune response against cancer. However, most of the investigations focus only on conventional cytotoxic cells, while ignoring the potential of unconventional T cells that until now have been little studied. γδ T cells are a unique lymphocyte subpopulation that has an extensive repertoire of tumor sensing and may have new immunotherapeutic applications in a wide range of tumors. The ability to respond regardless of human leukocyte antigen (HLA) expression, the secretion of antitumor mediators and high functional plasticity are hallmarks of γδ T cells, and are ones that make them a promising alternative in the field of cell therapy. Despite this situation, in particular cases, the leukemic microenvironment can adopt strategies to circumvent the antitumor response of these lymphocytes, causing their exhaustion or polarization to a tumor-promoting phenotype. Intervening in this crosstalk can improve their capabilities and clinical applications and can make them key components in new therapeutic antileukemic approaches. In this review, we highlight several characteristics of γδ T cells and their interactions in leukemia. Furthermore, we explore strategies for maximizing their antitumor functions, aiming to illustrate the findings destined for a better mobilization of γδ T cells against the tumor. Finally, we outline our perspectives on their therapeutic applicability and indicate outstanding issues for future basic and clinical leukemia research, in the hope of contributing to the advancement of studies on γδ T cells in cancer immunotherapy.

The Roles of γδ T Cells in Hematopoietic Stem Cell Transplantation

The αβ T-cell-depleted hematopoietic stem cell transplantation (HSCT) leads to lower relapse and better outcome, and may correlate strongly with expansion of donor-derived γδ T cells. γδ T cells play an important role in immune reconstitution and can exert a graft-versus-leukemia effect after HSCT. This review showed the recent literature on immune functions of γδ T cells after HSCT. The discrepancies between studies of γδ T cells in graft-versus-host disease may cause by its heterogeneous and various distinct subsets. And reconstitution of γδ T cells may play a potential immunoregulatory role in the infections after HSCT.

Impact of γδ T cells on clinical outcome of hematopoietic stem cell transplantation: systematic review and meta-analysis

Allogeneic hematopoietic stem cell transplantation (HSCT) using αβ T-/B-cell-depleted grafts recently emerged as a transplant strategy and highlighted the potential role of γδ T cells on HSCT outcomes. Our aim was to scrutinize available evidence of γδ T-cell impact on relapse, infections, survival, and acute graft-versus-host disease (aGVHD). We performed a systematic review and meta-analysis of studies assessing γδ T cells in HSCT. We searched PubMed, Web of Science, Scopus, and conference abstracts from inception to March 2019 for relevant studies. We included all studies that assessed γδ T cells associated with HSCT. Data were extracted independently by 2 investigators based on strict selection criteria. A random-effects model was used to pool outcomes across studies. Primary outcome was disease relapse. We also assessed infections, survival, and aGVHD incidence. The review was registered with PROSPERO (CRD42019133344). Our search returned 2412 studies, of which 11 (919 patients) were eligible for meta-analysis. Median follow-up was 30 months (interquartile range, 22-32). High γδ T-cell values after HSCT were associated with less disease relapse (risk ratio [RR], 0.58; 95% confidence interval [95% CI], 0.40-0.84; P = .004; I2 = 0%), fewer viral infections (RR, 0.59; 95% CI, 0.43-0.82; P = .002; I2 = 0%) and higher overall (HR, 0.28; 95% CI, 0.18-0.44; P < .00001; I2 = 0%) and disease-free survivals (HR 0.29; 95% CI, 0.18-0.48; P < .00001; I2 = 0%). We found no association between high γδ T-cell values and aGVHD incidence (RR, 0.72; 95% CI, 0.41-1.27; P = .26; I2 = 0%). In conclusion, high γδ T cells after HSCT is associated with a favorable clinical outcome but not with aGVHD development, suggesting that γδ T cells have a significant effect on the success of HSCT. This study was registered with PROSPERO as #CRD42019133344.

The effects of CTX damage or inhibition of bone marrow hematopoiesis and GM-CSF stimulation of bone marrow hematopoiesis on the peripheral blood TCRβ CDR3 repertoire of BALB/c mice

Objective: This paper aims to investigate the dynamic changes of the T-cell receptor (TCR) β complementarity-determining region 3 (CDR3) repertoire during cyclophosphamide or Cytoxan (CTX) damage or inhibition of bone marrow hematopoiesis caused by a reduction of peripheral blood white blood cells (WBCs) in BALB/c mice.Methods: We analyze TCR CDR3 repertoire of BALB/c mice including (1) NS control group (2) CTX damage group (3) CTX damage + GM-CSF recovery group (4) CTX damage + auto-recovery group.Results: The number of WBCs in the CTX group is significantly lower than that in the NS group and after GM-CSF injection, the GM-CSF group is higher than that in the NS group. The diversity of the CTX damage group is the highest and there is a significant difference in high-frequency clonal proliferation between the CTX damage group and CTX damage + GM-CSF recovery group compared with the NS control group. In addition, the numbers of unique productive CDR3 overlapping numbers in the four experimental groups are similar.Conclusions: These data reveal that CTX significantly reduced the number of WBCs and ratio of high-frequency TCR CDR3 sequences, and indirectly increased the diversity of the TCR CDR3 repertoire. GM-CSF quickly restored the number of WBCs, and partially restored changes in the TCR CDR3 repertoire induced by CTX. Results from monitoring the dynamic changes of the TCR CDR3 repertoire can be used to assess the effects of CTX and GM-CSF on the function of peripheral blood T cells and to explore the possible underlying mechanisms.

Gene expression pattern of TCR repertoire and alteration expression of IL-17A gene of γδ T cells in patients with acute myocardial infarction

BACKGROUND

γδ T cells are associated with the pathogenesis of coronary atherosclerotic heart disease, but the relationship between the development of acute myocardial infarction (AMI) and γδ T cells is not clear. So we attempt to investigate the expression pattern and clonality of T cell receptor (TCR) repertoire of γδ T cells in AMI patients, analyze the expression levels of regulatory genes Foxp3 and IL-17A, and characterize the correlation between γδ T cells and the pathogenesis of AMI.

METHODS

25 patients diagnosed with ST-segment-elevation AMI were enrolled and 14 healthy individuals were recruited as the controls. RT-PCR and GeneScan were used to analyze the complementarity-determining region 3 sizes of TCR γδ repertoire genes in sorted γδ T cells from peripheral blood mononuclear cells (PBMCs). RQ-PCR was used to detect the gene expression levels of Foxp3, IL-17A and TCR Vγ subfamilies in sorted γδ T cells. All the patients were followed up for recordings of clinical endpoints.

RESULTS

The mRNA gene expression levels of TCR Vγ1, Vγ2, and Vγ3 subfamilies in AMI patients were significantly higher than those in healthy controls. The expression pattern was Vγ1 > Vγ2 > Vγ3 in AMI patients, while Vγ1 > Vγ3 > Vγ2 in healthy controls. The significantly restricted expression of TCR Vδ subfamilies were also found in AMI patients. The expression frequencies of TCR Vδ7 and TCR Vδ6 in AMI patients were significantly lower than those in healthy controls. The high clonal expansion frequencies of the TCR Vδ8, Vδ4 and Vδ3 were determined in AMI patients. High expression of Foxp3 gene was found in AMI PBMCs, while high expression of IL-17A was found in AMI γδ+ cells.

CONCLUSIONS

Restrictive expression of TCR γδ repertoire and alteration expression of IL-17A gene are the important characteristics of γδ T cells in AMI patients, which might be related to the immune response and clinical outcome. γδ T cells might play a key role in the pathological progress of AMI and associated with the IL-17A mediated pathway.

Regulatory γδ T cells induced by G-CSF participate in acute graft-versus-host disease regulation in G-CSF-mobilized allogeneic peripheral blood stem cell transplantation

Background

The immunomodulatory effects of granulocyte colony-stimulating factor (G-CSF) on T cells result in a low incidence of acute graft-versus-host disease (aGVHD) in G-CSF-mobilized allogeneic peripheral blood stem cell transplantation (G-PBSCT). However, the exact mechanism remains unclear. Regulatory γδ T cells (γδTregs), characterized by the presence of TCRγδ and Foxp3, have aroused great concern in the maintenance of immune tolerance. We hypothesized that γδTregs might involve in the immunomodulatory effects of G-CSF mobilization.

Methods

The expression and immunomodulatory function of γδTreg subsets in peripheral blood of donors before and after G-CSF treatment in vivo and in vitro were evaluated by flow cytometry and CFSE assays. To investigate the effects of γδTregs on aGVHD, the association between γδTreg subsets in grafts and aGVHD in recipients was estimated.

Results

The proportions of Vδ1Tregs, CD27⁺Vδ1Tregs and CD25⁺Vδ1Tregs were significantly increased in peripheral blood after G-CSF treatment in vivo. γδTregs could be generated in vitro by stimulating with anti-TCRγδ in the presence of G-CSF. The immune phenotype, proliferation suppression function, and cytokine secretion of G-CSF-induced γδTregs were similar to that of transforming growth factor-β (TGF-β)-induced γδTregs. The clinical data demonstrated that the proportion of CD27⁺Vδ1Tregs in grafts was significantly lower in the patients who experienced aGVHD than in those who did not develop aGVHD (P = 0.028), and the proportions of other γδTreg subsets in grafts did not differ significantly between the two groups. The best cutoff value for CD27⁺Vδ1Treg proportion in grafts in prediction of aGVHD was 0.33%, with an area under the curve value of 0.725 (P = 0.043). Eight patients (26.7%) were classified as the low-CD27⁺Vδ1Treg group (< 0.33%), and 22 patients (73.3%) as the high-CD27⁺Vδ1Treg group (≥ 0.33%). The incidence of aGVHD was higher in the low-CD27⁺Vδ1Treg group than in the high-CD27⁺Vδ1Treg group (75.0% versus 22.7%, P = 0.028).

Conclusions

G-CSF could induce the generation of γδTregs in vivo and in vitro, and γδTregs might participate in aGVHD regulation in G-PBSCT.

Homeostatic γδ T Cell Contents Are Preserved by Granulocyte Colony-Stimulating Factor Priming and Correlate with the Early Recovery of γδ T Cell Subsets after Haploidentical Hematopoietic Stem Cell Transplantation

Emerging evidence from graft manipulations and immunotherapeutic treatments has highlighted a favorable effect of γδ T cells in the setting of allogeneic hematopoietic stem cell transplantation (alloHSCT). However, γδ T cell subsets and their distinct features in the allograft have not been characterized. Additionally, whether homeostatic γδ T cell fractions are influenced by treatment with granulocyte colony-stimulating factor (G-CSF) remains elusive. We initially compared the phenotypes of γδ T cell subsets, including CD27⁺, CD27^-, Vδ1⁺, Vδ2⁺, Vδ1⁺CD27⁺, Vδ1⁺CD27^-, Vδ2⁺CD27⁺, and Vδ2⁺CD27^- cells, in the peripheral blood of 20 healthy donors before and after G-CSF mobilization. The effects of G-CSF on the cytokine production capacities of γδ T cell subsets were also detected. Moreover, the correlation between donor homeostatic γδ T cell content and the early recoveries of γδ T cell subgroups after haploidentical HSCT was investigated in 40 pairs of donors and recipients. We found that both the proportions and IFN-γ secretion capacities of peripheral γδ T cell subsets were preserved in G-CSF-primed grafts. Homeostatic Vδ1 and Vδ2 proportions of donors significantly correlated with the early recoveries of Vδ1 and Vδ2 cells after haploidentical HSCT. Interestingly, a higher day 30 Vδ1 concentration was associated with a lower incidence of cytomegalovirus reactivation in recipients. These results not only clarify the preservation of γδ T cell phenotypes and functional features by G-CSF mobilization but also suggest the importance of homeostatic γδ T cell content for immune recovery after alloHSCT.

Oligoclonal expansion of TCR Vδ T cells may be a potential immune biomarker for clinical outcome of acute myeloid leukemia

Background

Recent data have shown that γδ T cells can act as mediators for immune defense against tumors. Our previous study has demonstrated that persisting clonally expanded TRDV4 T cells might be relatively beneficial for the outcome of patients with T cell acute lymphoblastic leukemia after hematopoietic stem cell transplantation (HSCT). However, little is known about the distribution and clonality of the TRDV repertoire in T cell receptor (TCR) of γδ T cells and their effects on the clinical outcome of patients with acute myeloid leukemia (AML). The aim of this study was to assess whether the oligoclonal expansion of TCR Vδ T cells could be used as an immune biomarker for AML outcome.

Findings

γδ T cells were sorted from the peripheral blood of 30 patients with untreated AML and 12 healthy donors. The complementarity-determining region 3 (CDR3) sizes of eight TCR Vδ subfamily genes (TRDV1 to TRDV8) were analyzed in sorted γδ T cells using RT-PCR and GeneScan. The most frequently expressed TRDV subfamilies in the AML patients were TRDV8 (86.67 %) and TRDV2 (83.33 %), and the frequencies for TRDV1, TRDV3, TRDV4, and TRDV6 were significantly lower than those in healthy individuals. The most frequent clonally expanded TRDV subfamilies in the AML patients included TRDV8 (56.67 %) and TRDV4 (40 %). The clonal expansion frequencies of the TRDV2 and TRDV4 T cells were significantly higher than those in healthy individuals, whereas a significantly lower TRDV1 clonal expansion frequency was observed in those with AML. Moreover, the oligoclones of TRDV4 and TRDV8 were independent protective factors for complete remission. Furthermore, the oligoclonal expansion frequencies of TRDV5 and TRDV6 in patients with relapse were significantly higher than those in non-recurrent cases.

Conclusions

To the best of our knowledge, we characterized for the first time a significant alteration in the distribution and clonality of the TRDV subfamily members in γδ T cells sorted from AML patients. Clonally expanded TRDV4 and TRDV8 T cells might contribute to the immune response directed against AML, while oligoclonal TRDV5 and TRDV6 might occur in patients who undergo relapse. While the function of such γδ T cell clones requires further investigation, TRDV γδ T cell clones might be potential immune biomarkers for AML outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-016-0353-3) contains supplementary material, which is available to authorized users.

The role of gamma delta T cells in haematopoietic stem cell transplantation

Although haematopoietic stem cell transplantation (HSCT) is a potential curative treatment for haematological malignancies, it is still a procedure associated with substantial morbidity and mortality due to toxicity, graft-versus-host disease (GVHD) and relapse. Recent attempts of developing safer transplantation modalities increasingly focuses on selective cell depletion and graft engineering with the aim of retaining beneficial immune donor cells for the graft-versus-leukaemia (GVL) effect. In this context, the adoptive and especially innate effector functions of γδ T cells together with clinical studies investigating the effect of γδ T cells in relation to HSCT are reviewed. In addition to phospho-antigen recognition by the γδ T cell receptor (TCR), γδ T cells express receptors of the natural killer (NK) and natural cytotoxicity (NCR) families enabling them to recognize and kill leukaemia cells. Antigen recognition independent from the major histocompatibility complex (MHC) allows for the theoretical possibility of mediating GVL without an allogeneic response in terms of GVHD. Early studies on the impact of γδ T cells in HSCT have reported conflicting results. Recent studies, however, do suggest an overall favourable effect of high γδ T cell immune reconstitution after HSCT; patients with elevated numbers of γδ T cells had a significantly higher overall survival rate and a decreased rate of acute GVHD compared to patients with low or normal γδ T cell counts. Further research in terms of effector mechanisms, subtypes and tissue distribution during the course of HSCT is needed to assess the potentially beneficial effects of γδ T cells in this setting.

Overexpression of MALT1-A20-NF-κB in adult B-cell acute lymphoblastic leukemia

Background

A20 is a dual inhibitor of NF-κB activation and apoptosis in the tumor necrosis factor receptor 1 signaling pathway, and both are related to tumorigenesis. A20 is frequently inactivated by deletions and/or mutations in several B and T cell lymphoma subtypes; however, knowledge of the role of A20 in B-cell acute lymphoblastic leukemia (B-ALL) remains limited. In this study, we characterized the A20 gene expression pattern, the expression level of its upstream regulating factor MALT1, and its downstream target NF-κB in adult B-ALL.

Methods

The expression level of MALT1, A20 and NF-κB1 was detected in peripheral blood mononuclear cells (PBMCs) from 20 patients with adult B-ALL (including 12 de novo B-ALL and 8 refractory/relapse B-ALL cases), and nine patients with B-ALL in complete remission (CR) using real-time PCR. Sixteen healthy individuals served as controls.

Results

Significant A20 overexpression was found in the B-ALL (median: 13.489) compared with B-ALL CR (median: 3.755) (P = 0.003) patients and healthy individuals (median: 8.748) (P = 0.002), while there was no significant difference in A20 expression between B-ALL CR patients and healthy individuals (P = 0.107). Interestingly, the A20 expression level in the B-ALL samples was relatively different with approximately 50% of the B-ALL cases showing a relatively high A20 expression level, while the remaining 50% cases demonstrated slight upregulation or a similar expression level as the healthy controls. However, there was no significant difference in the A20 expression level between de novo B-ALL (median 12.252) and refractory/relapse B-ALL patients (median 21.342) (P = 0.616). Similarly, a significantly higher expression level of NF-κB1 was found in the B-ALL (median 1.062) patients compared with healthy individuals (median 0.335) (P < 0.0001), while the NF-κB1 expression level was downregulated in the B-ALL CR group (median 0.339), which was significantly lower than that in those with B-ALL (P = 0.001). Moreover, the MALT1 expression level in B-ALL was upregulated (median 1.938) and significantly higher than that in healthy individuals (median 0.677) (P = 0.002) and B-ALL CR patients (median 0.153) (P = 0.008). The correlation of the expression levels of all three genes was lost in B-ALL.

Conclusions

We found that MALT1-A20-NF-κB is overexpressed in adult B-ALL, which may be related to the pathogenesis of B-ALL, and this pathway may be considered a potentially attractive target for the development of B-ALL therapeutics.

Electronic supplementary material

The online version of this article (doi:10.1186/s12935-015-0222-0) contains supplementary material, which is available to authorized users.

Upregulated TCRζ improves cytokine secretion in T cells from patients with AML

Previous studies indicated that upregulating TCRζ partially recovers T cell function in patients with leukemia. In this study, we characterized the cytokine profile of TCRζ-transfected T cells from acute myeloid leukemia (AML) patients by Quantibody®Array Glass Chip. Firstly, the significantly lower expression of TCRζ in CD3⁺/TCRζ⁺ cells from AML patients was found. Increased secretion of IL-2, IL-8, IL-10, IL-13, IFN-γ, TNF-α, GM-CSF, growth-regulated oncogene (GRO), MIP-1b, and regulated on activation, normal T cell expressed and secreted (RANTES) could be detected in T cells from AML patients after TCRζ upregulating. We concluded that upregulating TCRζ in T cells from AML can alter the secretion profile of cytokines and chemokine which are involved in T cell proliferation and activation.

The feature of distribution and clonality of TCR γ/δ subfamilies T cells in patients with B-cell non-Hodgkin lymphoma

Restricted T-cell receptor (TCR) Vα/Vβ repertoire expression and clonal expansion of αβ T cells especially for putative tumor-associated antigens were observed in patients with hematological malignancies. To further characterize the γδ T-cell immune status in B-cell non-Hodgkin lymphoma (B-NHL), we investigated the distribution and clonality of TCR Vγ/Vδ repertoire in peripheral blood (PB), bone marrow (BM), and lymph node (LN) from patients with B-NHL. Four newly diagnosed B-NHL cases, including three with diffuse large B-cell lymphoma (DLBCL) and one with small lymphocytic lymphoma (SLL), were enrolled. The restrictive expression of TCR Vγ/Vδ subfamilies with different distribution patterns could be detected in PB, BM, or LN from all of four patients, and partial subfamily T cells showed clonal proliferation. At least one clonally expanded Vδ subfamily member was found in PB from each patient. However, the expression pattern and clonality of TCR Vγ/Vδ changed in different immune organs and showed individual feature in different patients. The clonally expanded Vδ5, Vδ6, and Vδ8 were detected only in PB but neither in BM nor LN while clonally expanded Vδ2 and Vδ3 could be detected in both PB and BM/LN. In conclusion, the results provide a preliminary profile of distribution and clonality of TCR γ/δ subfamilies T cells in PB, BM, and LN from B-NHL; similar clonally expanded Vδ subfamily T cells in PB and BM may be related to the same B-cell lymphoma-associated antigens, while the different reactive clonally expanded Vγ/Vδ T cells may be due to local immune response.

Gene expression pattern of Treg and TCR Vγ subfamily T cells before and after specific immunotherapy in allergic rhinitis

BACKGROUND

T regulatory cell (Treg) plays a critical role in respiratory allergy and allergen-specific immunotherapy (SIT), and γδ T cells might participate in mediating Treg quantity and/or function in some immunological diseases. To further characterize whether γδ T cells could influence Treg in allergic rhinitis (AR) and SIT, we investigated the expression pattern of Treg's Foxp3 gene and γδ T cell receptor (TCR) Vγ subfamily genes in peripheral blood mononuclear cells (PBMCs) of AR patients before and after SIT.

METHODS

Eighteen AR patients undergoing effective SIT with house dust mite extract for one year were recruited. Visual Analogue Scale (VAS) was applied to evaluate the severity. Immunofluorescence quantification analysis was performed to determine the serum specific IgE (sIgE) content. Real-time PCR was used to detect the expression levels of Foxp3 and TCR Vγ subfamilies. Ten healthy volunteers were recruited as the controls.

RESULTS

Nasal uni-VAS score after SIT was significantly lower than that before SIT, while serum sIgE content was similar before and after SIT. Expression levels of Foxp3 and TCR Vγ subfamilies in AR patients before treatment were significantly lower than those in healthy subjects. Expression levels of VγI and II were similar before and after SIT, while expression levels of Foxp3 and VγIII after SIT were significantly higher than those before. Before SIT, the significant positive correlation was observed between expression levels of Foxp3 and VγI, II, III, while negative correlation was observed between Foxp3, VγIII and VAS. After SIT, the significant positive correlation between expression levels of Foxp3 and VγIII and negative correlation between Foxp3, VγIII and VAS were observed.

CONCLUSIONS

Treg and Vγ subfamily T cells were in a dynamic equilibrium in AR patients before and after effective immunotherapy for one year. The early improvement of symptoms following immunotherapy might be independent of the serum sIgE content in AR patients, but associated with the reconstitution of T cell immunity.