Functional leukemia-associated antigen-specific memory CD8+ T cells exist in healthy individuals and in patients with chronic myelogenous leukemia before and after stem cell transplantation

Abstract Antigens implicated in the graft-versus-leukemia (GVL) effect in chronic myeloid leukemia (CML) include WT1, PR1, and BCR-ABL. To detect very low frequencies of these antigen-specific CD8+ T cells, we used quantitative polymerase chain reaction (qPCR) to measure interferon-γ (IFN-γ) mRNA production by peptide-pulsed CD8+ T cells from HLA-A*0201+ healthy volunteers and from patients with CML before and after allogeneic stem cell transplantation (SCT). Parallel assays using cytomegalovirus (CMV) pp65 tetramers demonstrated the IFN-γ copy number to be linearly related to the frequency of tetramer-binding T cells, sensitive to frequencies of 1 responding CD8+ T cell/100 000 CD8+ T cells. Responses to WT1 and PR1 but not BCR-ABL were detected in 10 of 18 healthy donors. Responses to WT1, PR1, or BCR-ABL were observed in 9 of 14 patients with CML before SCT and 5 of 6 after SCT, often to multiple epitopes. Responses were higher in patients with CML compared with healthy donors and highest after SCT. These antigen-specific CD8+ T cells comprised central memory (CD45RO+CD27+CD57–) and effector memory (CD45RO–CD27–CD57+) T cells. In conclusion, leukemia-reactive CD8+ T cells derive from memory T cells and occur at low frequencies in healthy individuals and at higher frequencies in patients with CML. The increased response in patients after SCT suggests a quantitative explanation for the greater effect of allogeneic SCT.

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B and T Lymphocyte Attenuator Mediates Inhibition of Tumor-Reactive CD8+ T Cells in Patients After Allogeneic Stem Cell Transplantation

The Journal of Immunology ◽

10.4049/jimmunol.1102807 ◽

2012 ◽

Vol 189 (1) ◽

pp. 39-49 ◽

Cited By ~ 41

Author(s):

Willemijn Hobo ◽

Wieger J. Norde ◽

Nicolaas Schaap ◽

Hanny Fredrix ◽

Frans Maas ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

T Lymphocyte ◽

Cd8 T Cells ◽

Allogeneic Stem Cell Transplantation

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Increased proportion of perforin-expressing CD8+T-cells indicates control of herpesvirus reactivation in children after stem cell transplantation

Clinical Immunology ◽

10.1016/j.clim.2013.02.023 ◽

2013 ◽

Vol 148 (1) ◽

pp. 92-98 ◽

Cited By ~ 5

Author(s):

P.J. de Pagter ◽

J.J. Boelens ◽

R. Jacobi ◽

R. Schuurman ◽

N.M. Nanlohy ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Cd8 T Cells

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Expansion of Double Negative (CD3+ CD4- CD8-) T Cells After Stem Cell Transplantation

Pediatric Research ◽

10.1203/00006450-199905010-00194 ◽

1999 ◽

Vol 45 ◽

pp. 770-770

Author(s):

Daniel K Stachel ◽

Irene Schmid ◽

Friedhelm Schuster ◽

Rainer J Haas

Keyword(s):

T Cells ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Cd8 T Cells ◽

Double Negative

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CTL Responses Against Tumor Associated Antigens Are Part of the Graft Versus Leukemia-Effect and Protect from Relapse after Allogeneic Hematopoetic Stem Cell Transplantation.

Blood ◽

10.1182/blood.v110.11.3231.3231 ◽

2007 ◽

Vol 110 (11) ◽

pp. 3231-3231

Author(s):

Markus Kapp ◽

Stefan Stevanovic ◽

Kerstin Fick ◽

Juergen Loeffler ◽

Sen Mui Tan ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Cd8 T Cells ◽

T Cell Responses ◽

Proteinase 3 ◽

Post Transplantation ◽

Cell Responses

Abstract The Graft-versus-Leukemia (GVL) effect following allogeneic hematopoetic stem cell transplantation (HSCT) is one of the most prominent examples showing the ability of the immune system to eliminate malignant diseases. This effect was a strictly clinically described phenomenon, but in the last years T-cell responses against tumor-associated antigens (TAA) could partly be set in correlation with clinical benefit. Previously, TAA such as WT1 and proteinase-3 have been proposed as the targets for T-cells to establish a GVL effect. Now, we examined in addition other TAA (MUC1 and HM1.24) as possible T-cell targets of GVL related immune responses. We have defined new peptide epitopes from the MUC1 and HM1.24 antigens by the reverse immunology approach to increase the number of patients who can be screened and to expand the repertoire of immunologic monitoring as well as therapeutic approaches. A total of 25 patients after allogeneic stem cell transplantation have been screened and we are able to detect T-cell responses to both the MUC1 and HM1.24 antigens on top of the WT1 and the proteinase-3 antigen. Interestingly, we could detect a significant relationship between relapse and the absence of a T-cell response to TAA: Only 1/10 patients (10%) with TAA-specific CTL relapsed in contrast to 8/15 patients (53.3%) without TAA-specific CTL responses (p < 0.05). Furthermore, we demonstrated MUC1 peptides presented by HLA A*6801, B*0702 and B*4402 to be specifically recognized by CD3+/CD8+ T-cells. In conclusion, CD8+ T-cell responses directed to TAA might contribute to the GVL effect and are not limited to WT1 and proteinase-3. These observations clearly highlight both the importance and the potential of immunotherapeutic approaches in allogeneic stem cell recipients. Figure 1: New defined HLA class I epitopes predicted by computer analysis are recognized by specific CTL in patients post allogeneic HSCT. IFN-γ staining of PBMC from, patient No. 17 (AML, CR), 672 days post transplantation (A), patient No. 8 (AML, CR), 1035 days post transplantation (B) Cells were stimulated with 10μg/ml of the indicated peptides. Gates were set on lymphocytes by forward/side scattering (R1) and on CD3+/CD8+ cells (R2). Percentage numbers show peptide-specific CD3+/CD8+ T-cells from all CD3+/CD8+ T-cells. Figure 1:. New defined HLA class I epitopes predicted by computer analysis are recognized by specific CTL in patients post allogeneic HSCT. . / IFN-γ staining of PBMC from, patient No. 17 (AML, CR), 672 days post transplantation (A), patient No. 8 (AML, CR), 1035 days post transplantation (B) Cells were stimulated with 10μg/ml of the indicated peptides. Gates were set on lymphocytes by forward/side scattering (R1) and on CD3+/CD8+ cells (R2). Percentage numbers show peptide-specific CD3+/CD8+ T-cells from all CD3+/CD8+ T-cells.

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Lenalidomide Is Highly Effective in Patients with Relapsed Multiple Myeloma Following Allogeneic Stem Cell Transplantation and Increases the Frequency of CD4+FOXP3+ T Cells.

Blood ◽

10.1182/blood.v110.11.2722.2722 ◽

2007 ◽

Vol 110 (11) ◽

pp. 2722-2722

Author(s):

Monique C. Minnema ◽

Michael van der Veer ◽

Tineke Aarts ◽

Maarten Emmelot ◽

Tuna Mutis ◽

...

Keyword(s):

Multiple Myeloma ◽

T Cells ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cd8 T Cells ◽

Allogeneic Stem Cell Transplantation ◽

Response Rate ◽

Cell Populations ◽

Ifn Γ ◽

Grade 3

Abstract Lenalidomide has demonstrated significant clinical activity in patients with newly diagnosed and relapsed multiple myeloma (MM). Its actions are partly mediated by stimulation of cellular host anti–MM immunity. Given these potent immunomodulatory effects, we analysed whether lenalidomide could enhance graft versus tumour or graft versus Host (GvH) reactions and analysed the efficacy and toxicity of lenalidomide after allogeneic stem cell transplantation (allo-SCT). Lenalidomide 25 mg/day was given for 21 days followed by 1 week rest for a maximum of 6 cycles to 11 end-stage patients with relapsed MM following allo–SCT. Seven patients were refractory to their last treatment. From 5 patients peripheral blood was collected before, during and after lenalidomide treatment for analysis of CD4+, CD8+ T–cells, plasmacytoid and myeloid dendritic cells, regulatory T cells and NK cell populations by FACS. Also the percentage of CD4+FOXP3+ cells and IL–10 and IFN–γ producing CD4+ and CD8+ T cells were analysed by FACS. Dexamethasone 40 mg/day was added on day 1–4 and 15–18 at start of treatment in patients 2 and 5, or after 2 cycles in patients 3, 9 and 10. A high response rate was observed in these patients. Four patients developed complete (CR) or very good partial remissions (VGPR) after 1–5 treatment cycles. Three patients developed acute GvH disease (GvHD), grade 2–4. In 1 patient long lasting chronic GvHD was diminished, in another resolved. Other toxicities beyond CTC AE grade 1 were 1 patient with grade 3 diarrhoea, 1 with grade 3 muscular pain and 1 patient with grade 4 pulmonary embolism. There were 2 patients with leukocytopenia grade 3 and 4 and 2 patients with thrombocytopenia grade 2 and 3. Comprehensive immunomonitoring of 2 poor responders with stable disease (SD) or minimal response (MR) and 3 responders revealed generally no significant changes in dendritic cell populations, CD4+ and CD8+ T cells, CD56dim, CD56high and invariant NK cells. In 4/5 patients lenalidomide increased the frequency of IFN–γ producing CD4+ and CD8+ T cells. In 3/5 patients there was a decrease in the percentage of IL–10 producing CD8+ and CD4+ T cells. Remarkably, in 4/5 patients lenalidomide treatment induced a strong increase in the frequency of CD4+FOXP3+ T cells, which are considered to represent natural regulatory T cells (Tregs). In conclusion, our results reveal for the first time the potent effects with limited toxicity of lenalidomide in the allo–SCT setting with a response rate in 9 of 11 patients. In 4 of 5 patients tested we demonstrated an increase in Tregs and IFN–γ producing T cells, indicating that the action of lenalidomide is associated with immunomodulatory events involving both effector and Treg cell populations. Nr Age/Sex Refractory to last treatment Max Response/nr cycli GvHD FOXP3♣ IFNγ♣ IL-10♣ 1 62/F yes PR/2 BOS↓ nd nd nd 2 67/F yes PR/2 no nd nd nd 3 44/M yes PR/2 no 2,5↑ 3↑ 2↓ 4 62/F yes CR/4 no 0,3↓ 0 0 5 49/M yes PR/1 BOS = nd nd nd 6 64/M no PR/2 no nd nd nd 7 64/M no CR/4 acute gr 2, chronic↓ nd nd nd 8 56/F* yes VGPR/1 acute gr 4 5↑ 5↑ 2↑ 9 43/M no SD/2 no 5↑ 2↑ 2↓ 10 66/M yes VGPR/5 no nd nd nd 11 63/M† yes MR/1 acute gr 3 6↑ 2↑ 3↓

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Automated Generation of Antigen-Specific T Cells for Adoptive T Cell Therapy.

Blood ◽

10.1182/blood.v116.21.1177.1177 ◽

2010 ◽

Vol 116 (21) ◽

pp. 1177-1177

Author(s):

Melanie Fahrendorff ◽

Nanette von Oppen ◽

Georg Rauser ◽

Mario Assenmacher ◽

Juergen Schmitz ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Cd8 T Cells ◽

Allogeneic Stem Cell Transplantation ◽

Closed System ◽

Isolated Cells ◽

Ifn Gamma ◽

Cell Processing

Abstract Abstract 1177 The adoptive transfer of antigen-specific T cells can be a powerful tool for immunotherapy of malignant diseases or infectious complications after allogeneic stem cell transplantation (Riddell et al., 1992; Heslop et al. 2010). Human adenovirus (AdV), Epstein-Barr virus (EBV) or cytomegalovirus (HCMV) infections are frequent and often life-threatening complications post allogeneic stem cell transplantation. To reduce the time required to isolate antigen-specific T cells for adoptive transfer we have developed a method to isolate IFN-gamma-secreting CD4+ as well as CD8+ T cells after antigen-specific restimulation, the Cytokine Capture System IFN-gamma (CCS). Several preclinical studies demonstrate the efficient enrichment of functional CD4+ and CD8+ T cells specific for HCMV (Rauser et al., 2004), EBV (Hammer et al., 2007) or AdV (Feuchtinger et al. 2008) using the CCS. First clinical data of adoptively transferred HCMV-, EBV- or AdV-specific T cells into patients post allogeneic stem cell transplantation are very encouraging (Feuchtinger et al., 2010; Moosmann et al., 2010; Feuchtinger et al., 2006) with low T cell doses infused varying from 1–97×10e3 cells/kg. We have now developed a cell processing device for the automation of the CCS procedure. Antigen-specific stimulation, labeling with the CCS reagents, washing steps, cytokine capture, magnetic enrichment and potentially expansion of the isolated cells are performed fully automated in a closed system. At the beginning of the procedure all components including the cellular starting product, antigen(s), reagents, buffer, and media are connected to a sterile single-use closed system processing set in the device. Due to usage of sterile filters and sterile docking the whole process runs under sterile conditions. The cellular end product can be obtained in the medium/buffer of choice, with the desired cell concentration and volume. The cellular starting product can be leukapheresis or bone marrow and the yield of antigen-specific T cells depends on the frequency of IFN-gamma producing cells. When starting with 1×10e9 cells 1–20×10e5 HCMV-specific T cells could be isolated. Cell processing is possible overnight and the isolated cells might be used directly after enrichment or after a phase of in vitro expansion. Using this cell processing device, IFN-gamma secreting HCMV-specific T cells were enriched to the same purity (>80% IFN-gamma secreting CD4+ and CD8+ T cells) as with the semi-automated procedure. Cell loss during the procedure is markedly reduced, leading to an increased yield of IFN-gamma positive cells. An improved viability was observed resulting in better expansion rates. In conclusion, the automation in a closed system enables the fast and robust generation of antigen-specific T cells for adoptive therapy and will reduce clean room requirements. Disclosures: Fahrendorff: Miltenyi Biotec GmbH: Employment. von Oppen:Miltenyi Biotec GmbH: Employment. Rauser:Miltenyi Biotec GmbH: Employment. Assenmacher:Miltenyi Biotec GmbH: Employment. Schmitz:Miltenyi Biotec GmbH: Employment. Biehl:Miltenyi Biotec GmbH: Employment. Miltenyi:Miltenyi Biotec GmbH: Membership on an entity's Board of Directors or advisory committees.

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Exhaustion of CMV Specific T Cells with Enhanced PD-1 Expression In Persistent Cytomegalovirus Infection After Allogeneic Stem Cell Transplantation

Blood ◽

10.1182/blood.v116.21.3912.3912 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3912-3912 ◽

Cited By ~ 1

Author(s):

Tomonori Kato ◽

Tetsuya Nishida ◽

Miho Murase ◽

Makoto Murata ◽

Tomoki Naoe

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Cd8 T Cells ◽

Culture Media ◽

Cmv Infection ◽

Control Serum ◽

And Control

Abstract Abstract 3912 Cytomegalovirus (CMV) is one of the most common pathogens causing morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT), despite preemptive treatments employing antiviral drugs. Cytotoxic T cells are indispensable to control CMV infections. Chronic viral infections with human immunodeficiency virus or hepatitis C virus were shown to be associated with exhausted T cells with high expression of the inhibitory molecule programmed death 1 (PD-1). Recently, it has been reported that PD-1 up-regulation on CMV specific T cells was associated with CMV infection after renal and liver transplantation. PD-1 expression on CMV specific T cells after HSCT has not been well examined. We evaluated the involvements of exhausted CMV specific T cells characterized by high PD-1 expression in persistent CMV infection after allogeneic HSCT. Peripheral blood mononuclear cells (PBMC) and serum were obtained from an HLA-A*2402-positive patient who had received bone marrow transplantation from an HLA-A, B, C and DR matched unrelated donor. This patient failed to eliminate CMV for more than one year after transplantation despite intermittent administration of ganciclovir and foscarnet. Control PBMC and serum were obtained from an HLA-A*2402-positive healthy volunteer because the Japan Marrow Donor Program prohibits blood collection for research use from donor. All blood was collected with written informed consent. We at first analyzed frequencies of CMV-specific CD8+ T cells in patient and control PBMC by flow cytometer using QYDPVAALF/A*2402-specific tetramer and CD8 antibodies. QYDPVAALF is derived from CMV pp65 protein and presented by the HLA-A*2402 molecule. Tetramer stained cells were detected in the patient PBMC but control PBMC (0.11% versus undetectable). Patient and control PBMC were stimulated by a synthetic peptide QYDPVAALF in culture media containing IL-2 for 14 days, and stained with QYD/A*2402-specific tetramer. Remarkably, post-stimulated patient PBMC contained only 0.54% of tetramer stained CD8+ T cells, whereas a more dramatic increase (14.1%) in control PBMC. We analyzed frequencies of IFN-g secreting CD8+ T cells in PBMC after stimulation with a peptide pool covering the whole CMV pp65 protein for 4 hours. Less patient CD8+ T cells produced IFN-g, compared with the control CD8+ T cells (0.5% versus 1.1%) These data demonstrate dysfunction of CMV-specific CD8+ T cells in the patient with persistent CMV infection. To examine the mechanism of dysfunction of CMV-specific CD8+ T cells, we analyzed the expression of PD-1 on CMV-specific CD8+ T cells 14 days after stimulation with QYDPVAALF peptide. Multiparameter flow cytometry and tetramer assay exhibited higher expression of PD-1 on CMV-specific CD8+ T cells generated from patient PBMC, compared with CMV-specific CD8+ T cells generated from control PBMC. To find out whether the engagement of PD-1 to its ligand (PD-L1) leads to T cell exhaustion, we stimulated patient PBMC with QYDPVAALF peptide for 14 days in the presence or absence of anti PD-L1 antibody which blocks PD-1/PD-L1 inhibitory pathway. Blockade of PD-1/PD-L1 pathway resulted in 3.9-fold increase in patient CMV specific T cells. These findings demonstrate that PD-1 is associated with the exhaustion of CMV specific CD8+ T cells during persistent CMV infection in this patient. To examine the effect of patient serum on CMV specific CD8+ T cells, we stimulated patient PBMC with QYDPVAALF peptide for 14 days in culture media with patient or control serum. CMV specific CD8+ T cells increased 4-fold and 55-fold in the presence of patient and control serum, respectively. Patient serum led to higher PD-1 expression on CMV specific CD8+ T cells, compared with control serum (Fig). These findings suggest that patient serum may contain what regulates PD-1 expression level of exhausted T cells. Further investigations to identify factors regulating PD-1 expression in patient serum are in progress. The identification of the factors may provide new strategies to improve exhausted T cell function. Disclosures: No relevant conflicts of interest to declare.

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New Interleukin-15 Superagonist (IL-15 SA) Significantly Enhances Graft-Versus-Tumor Activity After Allogeneic Hematopoietic Stem Cell Transplantation

Blood ◽

10.1182/blood.v122.21.3254.3254 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3254-3254

Author(s):

Cavan P Bailey ◽

Christopher Sauter ◽

Michelle M Panis ◽

Tulin Budak-Alpdogan ◽

Hing Wong ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Cd8 T Cells ◽

T Cell Proliferation ◽

Hematopoietic Stem ◽

Interleukin 15 ◽

And Function

Abstract Interleukin-15 (IL-15) is a pleiotropic cytokine, which plays various roles in the innate and adaptive immune system, including the development, activation, homing and survival of immune effector cells. IL-15 has been previously shown to increase CD8+ T and NK cells number and function in normal mice and recipients of stem cell transplantation. However, obstacles remain in using IL-15 therapeutically, specifically its low potency and short in vivo half-life. To overcome this, a new IL-15 mutant (IL-15N72D, J. Immunol, 2009; 183:3598) has been developed, with increased biological activity. Co-expressing IL-15N72D, in conjunction with IL-15RαSu/Fc produced a biologically active and highly potent IL-15 superagonist complex (IL-15SA, also known as ALT-803, Cytokine, 2011; 56:804). We evaluated the effects of IL-15-SA on immune reconstitution and graft-versus-tumor (GVT) activity in recipients of allogeneic hematopoietic stem cell transplantation (HSCT). Lethally irradiated BALB/c recipients were transplanted with T-cell depleted (TCD) bone marrow (BM) cells from B6 mice. IL-15 SA was administered via IP injection in two doses on days +17 and +24 after transplant. Animals were sacrificed at day 28. Administration of IL-15 significantly increased the numbers of CD8+ T cells and NK cells. IL-15 SA also augmented interferon-γ secretion from CD8+ T cells. We observed similar activity in B6CBA→CB6F1 transplant model. Interestingly IL-15 SA upregulates NKG2D and CD107a expression on CD8+ T cells. IL-15 SA administration also specifically increased slow-proliferative CD8+ T-cell proliferation in conjunction with robust IFN-γ and TNF-α secretion in CD8+ T cells in recipients of CFSE (carboxyfluorescein succinimidyl ester) labeled-T-cell infusion, whereas there was no effect on CD4+ T-cell proliferation. We then tested the anti-tumor activity of IL-15 SA in three different tumor models; murine mastocytoma (P815), murine B cell lymphoma (A20) and murine renal cell carcinoma (Renca). We found that IL-15 SA administration enhanced GVT activity against P815 and A20 in recipients of allogeneic HSCT though this activity required a low-dose T cell infusion with HSCT. Interestingly, augmented GVT activity against to Renca after IL-15 SA administration in recipients of allogeneic HSCT did not require T cell infusion. We conclude that IL-15 SA is a very potent cytokine complex for enhancing CD8+ and NK cell reconstitution and function after HSCT, which would be a candidate for post-transplant immunotherapy. Disclosures: Wong: Altor Bioscience: Employment.

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Immunosenescent Characteristics of T Cells in Young Patients Following Haploidentical Stem Cell Transplantation from Parental Donors

Blood ◽

10.1182/blood-2019-125282 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 3283-3283

Author(s):

Ga Hye Lee ◽

Kyung Taek Hong ◽

Jung Yoon Choi ◽

Hee Young Shin ◽

Won-Woo Lee ◽

...

Keyword(s):

Dna Damage ◽

T Cells ◽

Stem Cell ◽

T Cell ◽

Hematopoietic Stem Cell Transplantation ◽

Stem Cell Transplantation ◽

Telomere Length ◽

Cell Transplantation ◽

Cd8 T Cells ◽

Hematopoietic Stem

Introduction: Pediatric and adolescent patients in need of allogeneic hematopoietic stem cell transplantation generally receive stem cells from older, unrelated or parental donors when a sibling donor is not available. Despite encouraging clinical outcomes, it has been suggested that immune reconstitution accompanied by increased replicative stress and a large difference between donor and recipient age may worsen immunosenescence in pediatric recipients. Therefore, in this study paired samples were collected at the same time from donors and recipients of haploidentical hematopoietic stem cell transplantation (HaploSCT). Methods: We conducted flow cytometry-based phenotypic and functional analyses and telomere length measurements of 21 paired T-cell sets from parental donors and children who received T cell-replete HaploSCT with post-transplant cyclophosphamide (PTCy) at Seoul National University Children's Hospital between February 2014 and January 2017. The conditioning regimen was comprised of targeted busulfan (total target area under the curve, 75,000 mg•h/L) with intensive pharmacokinetic monitoring, fludarabine and cyclophosphamide. Results: Fourteen pediatric, adolescent, and young adult patients with malignant disease and seven with nonmalignant disease were included with a median post-transplantation period of 16.9 months (range, 12.4-38.8). Senescent T cells, CD28- or CD57+ subsets of both CD4+ and CD8+ T cells, were significantly expanded in patients compared with parental donors. Further, not only CD4+CD28- T cells, but also CD4+CD28+ T cells showed reduced cytokine production capacity and impaired polyfunctionality compared with parental donors, whereas their TCR mediated proliferation capacity was comparable. Of note, the telomere length in patient T cells was preserved, or even slightly longer, in senescent T cells compared with donor cells. We also found that the patients had a higher level of γ-H2AX-expressing CD28- senescent T cells compared with the donors, which is used as a DNA damage marker. Regression analysis showed that senescent features of CD4+ and CD8+ T cells in patients were influenced by donor age and the frequency of CD28- cells, respectively. Conclusions: Our data suggest that T cells undergo premature immunosenescent changes and exhibit functional defects in pediatric HaploSCT recipients. Further, there is an increased level of DNA damage in patient CD4+ T cells compared to those of parental donors. Therefore, long-term, comprehensive immune monitoring of these patients is necessary. Disclosures No relevant conflicts of interest to declare.

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A Pilot Study of Mycophenolate Mofetil for the Prophylaxis and Treatment of Graft-Versus-Host Disease.

Blood ◽

10.1182/blood.v110.11.4969.4969 ◽

2007 ◽

Vol 110 (11) ◽

pp. 4969-4969

Author(s):

Chengwei Luo ◽

Xin Du ◽

Jianyu Weng ◽

Rong Guo ◽

Zesheng Lu

Keyword(s):

T Cells ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Graft Versus Host Disease ◽

Cd8 T Cells ◽

Peripheral Blood Stem Cell ◽

Host Disease ◽

Graft Versus Host ◽

Gvhd Prophylaxis

Abstract Graft-versus-host disease (GVHD) is a serious complication of allogeneic peripheral blood stem cell transplantation (PBSCT), which contribute to morbidity and mortality after transplantation. Approximately half of the patients that undergo allogeneic stem cell transplantation develop severe acute or chronic graft-versus-host disease [Shulman HM et al. Am J Med, 1980], which varies with the degree of histoincompatibility, the recipient and donor ages, the source and quality of donor T lymphocytes, the incidence of cytomegalovirus infection,and type of GVHD prophylaxis strategy. The combination of immunosuppressive drugs, CsA and short-course MTX is a standard regiment for prevention of GVHD after BMT [Nademanee A et al. Blood, 1995], and have been shown in randomize trials to be superior to either drug alone in preventing severe GVHD [Storb R N Engl J Med.1986]. Although the efficacy of the regimens in preventing GVHD, the incidence reported for GVHD after transplantation is 38–68%. Each of these agents is also associated with significant organ toxicity. MMF is an new immunosuppressive drug, which selectively inhibits proliferation of T and B lymphocytes, formation of antibodies, and glycosylation of adhesion molecules by inhibition purine nucleotide synthesis and depleting the lymphocytes and monocytes of guanosine triphosphate. In patients undergoing renal and heart transplantation, it has been successfully used to prevent graft rejection [Lang P et al.Transplantation, 2005]. We compared the effects of MMF+ CsA+ MTX as GVHD prophylaxis vs CsA + MTX in patients undergoing allogeneic peripheral blood stem cell transplantation. In all, 33 patients were enrolled in this study. The first group, of 16 patients, received CsA at 3mg/kg i.v. from day −1 to +30 day and MTX was on 15mg/m2 day +1 and 10mg/m2 day +3, +6, +11. The other group, of 17 patients received MMF 1g/d day −7 until day 0 and CsA + MTX. Here we used flow cytometric analysis technique to measure the changes of T cell subsets before and after treatment of MMF and CsA. Our study showed the incident of aGVHD is 25% when we combined standard GVHD proplylaxis with MMF after PBSCT, Which significantly reduce the risk of aGVHD than the combination of CsA and MTX (58.8%). Therefore, MMF is an effective drug in prophylaxis of aGVHD. Chronic GVHD is a late complication of PBSCT, Which develops approximately 30% in related donor HLA-matched allografts, and 60–70% in HLA-unmatched. The incident is not reduce with the development of aGVHD prophylaxis, Our result showed that the incident of cGVHD in research group (25%) is the same as the control group (23.5%). It seems that MMF is not reduce the incident of cGVHD, which may be different frome aGVHD. Our conclude that the number of CD3+ CD4+T cells decreased after the treatment of MMF, and those of CD3+ CD8+T cells increased,with reduction of the CD4+/CD8+ ratio. the number of CD25+ CD4+ and CD69+ CD8+ T cells were all increase. It seems that MMF may preferably effect on the CD3+CD4+T cells and the combination of MMF with CSA and MTX can significantly reduce the incidence of acute graft-vost-host diease, It appears to have a synergic action with CSA for the treatment of aGVHD.

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