Naive and Non Naive CD4+ and CD8+ T Cell Subsets Distribution in Blood and Marrow Grafts and Their Impact on Patients’ Outcome after Allogeneic Stem Cell Transplantation.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1240-1240
Author(s):  
Ibrahim Yakoub-Agha ◽  
Pasquine Saule ◽  
Claudine Grutzmacher ◽  
Pascale Cracco ◽  
Leo Magro ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
T Cell ◽  
Acute Gvhd ◽  
Cd8 T Cell ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Cd8 Cells ◽  
Immune Parameters ◽  
The Impact

Abstract Peripheral G-CSF-mobilized blood stem cells (PBSC), use as alternative to marrow stem cells (MSC), is associated with enhanced engraftment and accelerated hematopoietic recovery after allo-SCT. However, despite an increased number of donor T cells infused, the incidence of acute GVHD with PBSC appears to remain identical or less than with MSC. Recent works on the heterogeneity of the human CD4+ and CD8+ T cells have individualized 4 subsets: namely, naive (CCR7+CD45RA+), central memory (TCM, CCR7+CD45RA−), effector memory (TEM, CCR7−CD45RA−), and CD45RA+ effector memory cells (TEMRA, CCR7−CD45RA+). To our knowledge, the T cell subsets proportions in MSC and PBCSP grafts remain unknown. The impact of the infused T cell subsets on patients’ outcome is still to be investigated. Between September 2003 and July 2004, 25 consecutive hematopoietic allo-SCT (12 MSC and 13 PBSC) were considered for this study. Multiple combinations of immunophenotyping analysis were used to prospectively examine immune parameters related to graft as well as to early reconstitution. Early post-transplant complications including acute GVHD, relapse and infections were assessed. As expected, T cells subsets, B cells and NK cells numbers were significantly higher in PBSC grafts (versus MSC). However, proportions of CD4+ and CD8+ T-cell subsets were comparable in the 2 types of graft and similar to normal values observed with peripheral blood of healthy adults. Table below summarize the distribution of T cell subsets within T CD4+ and T CD8+ in the two types of graft. The incidence of acute GVHD was significantly higher in pts receiving > 5% of CD8+ TEM cells among infused CD8+ cells (p<0.05) suggesting a detrimental role of this CD8+ subset. Pts who developed acute GVHD, compared to those who did not, had a faster expansion of CD4+ and CD8+ TEM cells (p<0.003), and CD8+ TEMRA cells (p<0.05) after transplantation. Conclusion: this report contributes to the establishment of reference values regarding the distribution of T cell subsets within PBSC and MSC graft. Although, the quantity of infused T cell does not seem to influence early complications after allo-SCT, the qualitative composition of graft regarding T cell subsets, appears to be of great importance in acute GVHD occurrence. MSC PBSC CD4+ naive 45% 48% CD4+ TCM 25% 24% CD4+ TEM 20% 16% CD4+ TEMRA 5% 2% CD8+ naive 40% 50% CD8+ TCM 4% 7% CD8+ TEM 23% 14% CD8+ TEMRA 29% 22%

Phenotypic and Functional Analysis of T-Cells Mobilized in HLA-Matched Sibling Donors Following Treatment with the Chemokine Antagonist AMD3100.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3001-3001 ◽  
Author(s):  
Michael Rettig ◽  
Steven M. Devine ◽  
Julie Ritchey ◽  
John F. DiPersio
Keyword(s):  
T Cells ◽  
T Cell ◽  
Peripheral Blood ◽  
Acute Gvhd ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Phenotypic Properties ◽  
Functional Changes ◽  
Cd8 Cells ◽  
Matched Sibling

Abstract We are currently evaluating a novel method for the procurement of peripheral blood stem cells from HLA matched sibling donors using a direct antagonist of the CXCR4/SDF-1 interaction called AMD3100 (A). Donors receive a single subcutaneous injection of A and then undergo a 20 liter leukapheresis (LP) four hours later. The LP product is then cryopreserved and subsequently transplanted following ablative conditioning. To date, we have performed 15 transplants with allografts collected following A alone. In comparison to allografts collected following five days of G-CSF, A mobilized allografts contain approximately 50% less CD34+ cells but 2–3 times more CD3+ cells. Nevertheless, the kinetics of neutrophil and platelet engraftment have been virtually identical to that observed following G-mobilized allografts and grades 2–4 acute GVHD has been observed in only 20% of recipients. We sought to analyze the functional and phenotypic properties of T cells collected following A alone to understand the relatively low rates of acute GVHD despite the transplantation of higher T-cell doses. In 3 donors, extensive T cell phenotyping was performed on donor peripheral blood prior to A, 6 hours following A, and also on the LP product collected after A. Specifically, we were seeking to determine whether any alteration in CD4+ or CD8+ subsets had occurred. We analyzed T-cell subsets using well described markers for central memory, effector memory, naïve, and effector memory RA phenotypes. We also assessed expression of CD62L, CD127, CCR7, and SLAM family members (CD48, CD150, and CD244) on both CD4+ and CD8+ cells. The activation status on CD4 and CD8 cells was assessed using markers for CD25, CD30, and CD69. Finally we assessed for quantitative changes in the mobilization of regulatory T cells by assaying the proportion of CD4+CD25+FoxP3+ cells mobilized following A. In none of these analyses could we detect any significant alteration in the relative ratios of CD4 or CD8 subsets mobilized by A. Finally, the functional capacity of purified CD3+ cells collected following A was assessed using a NOD/SCID xenogeneic GVHD model we have recently developed. In that model, survival of mice transplanted with A mobilized T-cells was similar to that observed with untreated T cells, suggesting that A mobilized T cells retain their GVHD-inducing capacity. In summary, these preliminary data suggest that AMD3100 induces a “pan-mobilization” of T cell subsets without any apparent skewing toward a particular subset. These studies are in contrast to others suggesting subtle phenotypic and functional changes in donor T cells after mobilization with G-CSF. Further studies evaluating A mobilized allografts are ongoing.

scholarly journals Mitochondrial Dysfunction Associates With Acute T Lymphocytopenia and Impaired Functionality in COVID-19 Patients

2022 ◽  
Vol 12 ◽  
Author(s):  
Yufei Mo ◽  
Kelvin Kai-Wang To ◽  
Runhong Zhou ◽  
Li Liu ◽  
Tianyu Cao ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mitochondrial Dysfunction ◽  
Cd8 T Cells ◽  
Functional Impairment ◽  
Cell Loss ◽  
Cd8 T Cell ◽  
Underlying Mechanism ◽  
T Cell Subsets ◽  
Effector Memory

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection results in rapid T lymphocytopenia and functional impairment of T cells. The underlying mechanism, however, remains incompletely understood. In this study, we focused on characterizing the phenotype and kinetics of T-cell subsets with mitochondrial dysfunction (MD) by multicolor flow cytometry and investigating the association between MD and T-cell functionality. While 73.9% of study subjects displayed clinical lymphocytopenia upon hospital admission, a significant reduction of CD4 or CD8 T-cell frequency was found in all asymptomatic, symptomatic, and convalescent cases. CD4 and CD8 T cells with increased MD were found in both asymptomatic and symptomatic patients within the first week of symptom onset. Lower proportion of memory CD8 T cell with MD was found in severe patients than in mild ones at the stage of disease progression. Critically, the frequency of T cells with MD in symptomatic patients was preferentially associated with CD4 T-cell loss and CD8 T-cell hyperactivation, respectively. Patients bearing effector memory CD4 and CD8 T cells with the phenotype of high MD exhibited poorer T-cell responses upon either phorbol 12-myristate-13-acetate (PMA)/ionomycin or SARS-CoV-2 peptide stimulation than those with low MD. Our findings demonstrated an MD-associated mechanism underlying SARS-CoV-2-induced T lymphocytopenia and functional impairment during the acute phase of infection.

Proportions of T-Cell CD8+ Subsets Lacking CD28 Expression at Day 30 after Myeloablative Allogeneic Stem Cell Transplantation Are Predictive for Relapse and Chronic GVHD.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2979-2979
Author(s):  
Ibrahim Yakoub-Agha ◽  
Pasquine Saule ◽  
Leonardo Magro ◽  
Pascale Cracco ◽  
Valerie Coiteux ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Chronic Gvhd ◽  
Immunosuppressive Treatment ◽  
Cd8 T Cell ◽  
T Cell Subsets ◽  
Mixed Chimerism ◽  
Effector Memory ◽  
Myeloablative Conditioning ◽  
Risk Of Relapse

Abstract The curative potential of allo-SCT for malignancies derives from the progressive reconstitution of the immune system and the development of effective anti-tumor immunity, but GVHD and disease relapse remain considerable obstacles to improvement in overall outcomes. Because in recipients target antigens are persisting, donor-derived T-cell responses may be expected to lead to the accumulation of a sizable proportion of differentiated T-cells, as happens following infection with persisting pathogens. A few cross-sectional studies have pointed to the preponderance of certain memory T-cell subsets associated with chronic GVHD (cGVHD), but the subset identified differed between studies. Inasmuch as qualitative T-cell recovery takes months to years to complete and there is substantial variability in time to development of GVHD or relapse, serial analysis might be more suitable to unveil early changes in T-cell subset composition attributable to transplantation-related events. From October 2003 on, 55 pts who underwent an allo-SCT after myeloablative conditioning were monitored prospectively in terms of clinical post-graft complications, including graft rejection, infections, GVHD and relapse. Blood samples were obtained on days 30±2, 60±3, 90±5, 180±10 and 365±15 post-transplant. Naive (CD45RA+CCR7+), central memory (TCM, CD45RAnegCCR7+), effector memory (TEM, CD45RAnegCCR7neg), and terminally differentiated effector (TTD, CD45RA+CCR7neg) were enumerated within the CD4+ and CD8+ pools, and the percentage of cells coexpressing CD28 was calculated within each eight subsets. The degree of donor-derived T-cell chimerism was assessed by real time PCR (sensitivity ≤ 1%). Median follow-up was 733 d (404–1251). Dynamics of CD4+ and CD8+ naive, TCM, TEM, and TTD were similar between the pts who developed cGVHD (n=15) and those who did not and between pts who relapsed and those who did not. However, costaining to detect CD28 demonstrated contrasting differences between cGVHD and relapse. At day 30, pts who subsequently relapsed (n=17) had elevated percentages of cells keeping CD28 expression within CD8+ T-cell subsets (TCM, p=.001; TCM, p=.021; and TTD, p=.007). Conversely, pts who subsequently developed cGVHD (n=15; only one relapsed) had diminished percentages of CD28+ cells within the two CD8+CCR7+ subsets at day 30 (p=.002 and p=.034, respectively). Loss of CD28 expression is known to be a hallmark of CMV infection but multivariate analysis ruled out, however, a confounding effect of CMV. Adjusted hazard ratios were 0.10 (95% CI, 0.01-0.76; p=.026) and 5.56 (95% CI, 1.16-25.00; p=.032) with CD28neg cells 16.7% of all CD8+ TCM at day 30 for relapse and cGVHD, respectively. Furthermore, pts with relapse had more often mixed chimerism at day 30 while those with cGVHD had more often full-donor chimerism (p=.042 and p=.023, respectively). CONCLUSION: This prospective study is the first to associate an early contrasting change in CD8+CD28neg T-cells with the risk of relapse and cGVHD after a myeloablative conditioning. Determination at day 30 of the proportions of CD8+ T-cell subsets expressing CD28 and of the level of T-cell chimerism could assist in predicting risk of relapse and cGVHD and help build an algorithm for the management of immunosuppressive treatment.

TNFR2 Is Expressed Preferentially By Late Differentiated CD8 T-Cells and Can be Triggered By TNFR2-Specific Ligand to Induce Cell Death of Recently Activated Antigen-Specific T Cells: A Possible Role of TNFR2 in T-Cell Deflation

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4352-4352
Author(s):  
Mohammad Raeiszadeh ◽  
Matthew Verney ◽  
Charles Craddock ◽  
Harald Wajant ◽  
Paul Moss ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd8 T Cell ◽  
Receptor Expression ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Cell Transplant ◽  
Gamma Chain ◽  
Transplant Patients

Abstract Recent evidence suggests that Tumor Necrosis Factor (TNF) can selectively kill antigen-specific autoreactive CD8+ T-cells through engagement with TNF Receptor 2 (TNFR2) (1). Within the immune system, TNFR2 expression is restricted to subsets of T-cells, a profile which is in marked contrast to the ubiquitous pattern of expression of TNFR1. However, the spectrum and physiological significance of TNFR2 expression by CD8+ T-cell subpopulations is unknown. In this study we analysed the expression of TNFR2 by CD8 T-cell subsets isolated from normal healthy donors by flow cytometry. In addition, in order to understand the physiological significance of TNFR2 expression on recently activated T cells, we further studied expression on CMV-specific CD8 T-cells which expanded in stem cell transplant patients in response to episodes of CMV reactivation. The expression of TNFR2 was compared to that of other common gamma chain receptors including IL2R and IL7R, and to the expression of a receptor for inflammatory cytokine IL6. TNFR2 expression was found to increase during differentiation of CD8+ T cells. In particular, TNFR2 expression was seen on 6.5% of naïve, 14.6% of central memory, 37.9% of effector memory and 45.2% of CD45RA-revertant effector memory (TEMRA) CD8+ T cells. In contrast, common gamma chain cytokine receptor expression was skewed towards less differentiated T-cell subsets. For example, IL-7R was expressed by 63% of central memory populations but only 18.4% of the TEMRA subset. Comparable expression of IL2R was 12.1% on TCM and 2% on TEMRA. Of interest, IL-6 receptor expression was predominantly expressed by naïve CD8 T-cells (69.5%). In support of these results, we went on to show that expression of TNFR2 was inducible on primary T cells following activation with anti-CD3 and IL-2 in vitro. Healthy CMV seropositive donors had a larger median number of CD8+ T cells expressing TNFR2 (53%) in comparison to CMV seronegative donors (15%), (p<0.0001), consistent with the known accumulation of differentiated T-cells within CMV seropositive individuals.The expression of TNFR2 was then examined on CMV-specific CD8 T-cells which were undergoing acute expansion in response to viremia in six haemopoietic stem cell transplant patients. The expansion of CMV-specific CD8 T-cells was accompanied by an increase in the intensity of TNFR2 expression which later decreased during the retraction of antigen-specific T-cells during resolution of viremia. In order to explore the functional significance of TNFR2 expression, T-cells isolated from healthy donors were treated with recombinant TNFR2-specific ligand. This induced cell loss ranging from 13% to 60% of all CD8 T-cells in relation to untreated control cells, with selective depletion of the TNFR2+ population. A similar proportion of CMV-specific T-cells from transplant patients were eliminated by ex vivo stimulation of TNFR2. In conclusion our work shows that TNFR2 expression increases during differentiation of CD8+ T cells. In addition, we were able to utilize virus-specific T cells from SCT patients to show that expression is increased during the acute response to stimulation with antigen. We also provide evidence that TNFR2 activation can lead to the partial elimination of antigen-specific CMV-specific T-cells and it may thus play an important role in the ‘deflation’ of a pathogen-specific T-cell immune response following resolution of infection. These data suggest that TNFR2 expression may act as a ligand to signal activation-induced cell death in late differentiated populations of CD8+ T cells. Further investigations are required to assess the molecular pathways of TNFR2 signalling that are activated following receptor ligation in vivoand whether or not these are disrupted in disorders associated with chronic CD8+ T cell lymphproliferation. (1) L. Ban et al, PNAS 2008, 105: 3644 Disclosures No relevant conflicts of interest to declare.

scholarly journals Interplay between IL-10, IFN-γ, IL-17A and PD-1 Expressing EBNA1-Specific CD4+ and CD8+ T Cell Responses in the Etiologic Pathway to Endemic Burkitt Lymphoma

Cancers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 5375
Author(s):  
Catherine S. Forconi ◽  
David H. Mulama ◽  
Priya Saikumar Lakshmi ◽  
Joslyn Foley ◽  
Juliana A. Otieno ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Burkitt Lymphoma ◽  
Cd4 T Cells ◽  
Cd8 T Cell ◽  
T Cell Response ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Healthy Children ◽  
Ifn Γ

Children diagnosed with endemic Burkitt lymphoma (eBL) are deficient in interferon-γ (IFN-γ) responses to Epstein–Barr Nuclear Antigen1 (EBNA1), the viral protein that defines the latency I pattern in this B cell tumor. However, the contributions of immune-regulatory cytokines and phenotypes of the EBNA1-specific T cells have not been characterized for eBL. Using a bespoke flow cytometry assay we measured intracellular IFN-γ, IL-10, IL-17A expression and phenotyped CD4+ and CD8+ T cell effector memory subsets specific to EBNA1 for eBL patients compared to two groups of healthy children with divergent malaria exposures. In response to EBNA1 and a malaria antigen (PfSEA-1A), the three study groups exhibited strikingly different cytokine expression and T cell memory profiles. EBNA1-specific IFN-γ-producing CD4+ T cell response rates were lowest in eBL (40%) compared to children with high malaria (84%) and low malaria (66%) exposures (p < 0.0001 and p = 0.0004, respectively). However, eBL patients did not differ in CD8+ T cell response rates or the magnitude of IFN-γ expression. In contrast, eBL children were more likely to have EBNA1-specific CD4+ T cells expressing IL-10, and less likely to have polyfunctional IFN-γ+IL-10+ CD4+ T cells (p = 0.02). They were also more likely to have IFN-γ+IL-17A+, IFN-γ+ and IL-17A+ CD8+ T cell subsets compared to healthy children. Cytokine-producing T cell subsets were predominantly CD45RA+CCR7+ TNAIVE-LIKE cells, yet PD-1, a marker of persistent activation/exhaustion, was more highly expressed by the central memory (TCM) and effector memory (TEM) T cell subsets. In summary, our study suggests that IL-10 mediated immune regulation and depletion of IFN-γ+ EBNA1-specific CD4+ T cells are complementary mechanisms that contribute to impaired T cell cytotoxicity in eBL pathogenesis.

scholarly journals PD-1-Mediated T Cell Exhaustion Is Prevalent Among Patients with MPN-Associated Myelofibrosis Independent of JAK1/2 Inhibition

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5487-5487
Author(s):  
Ivo Veletic ◽  
Taghi Manshouri ◽  
Graciela M. Nogueras González ◽  
Sanja Prijic ◽  
Joseph E. Bove ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Board Of Directors ◽  
Central Memory ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Spleen Size ◽  
Advisory Committees ◽  
Cd8 Cells ◽  
Circulating T Cells

Abstract Background: Primary myelofibrosis (PMF), post-polycythemia vera MF (post-PV MF) and post-essential thrombocythemia MF (post-ET MF) are characterized by expansion of the neoplastic clone and by progressive bone marrow (BM) fibrosis. Like in other hematologic malignancies, in most patients with MF the immune system is significantly deregulated: MF patients' plasma cytokine and chemokine levels are markedly increased and their normal T cell subset distribution is significantly altered. Although treatment with the Janus kinase (JAK)-1/2 inhibitor ruxolitinib significantly decreases cytokine/chemokine levels, reduces spleen size, and improves symptoms and quality of life, it does not reverse BM fibrosis nor does it halt the propagation of the neoplastic clone. The T cell immune checkpoint programmed cell death protein-1 (PD-1) promotes immune tolerance by binding to the tumor's cell surface PD-1 ligand (PD-L1). Whereas the importance of T cell-mediated immune tolerance in MF has been documented and trials evaluating clinical benefits of PD1/PD-L1 checkpoint inhibition are ongoing, little is known about the effect of ruxolitinib on PD-1 expression in T cell subsets. Therefore we systematically analyzed MF patients circulating T cells' surface marker expression prior to and during ruxolitinib treatment. Methods: Peripheral blood cells were obtained from well-characterized PMF, post-PV MF and post-ET MF patients prior to and during the course of treatment with ruxolitinib (n=47) and, as control, from age-matched healthy donors (n=28). The proportion of PD-1-expressing CD4+ and CD8+ cells was assessed using multiparameter flow cytometry. Naïve, central memory, effector memory, and effector T cell subsets were defined based on CD45RO and CD27 cell surface antigen expression. Results: A significantly high number of circulating T cells co-expressing CD4+/PD-1+ and CD8+/PD-1+ was found in MF patients compared to age-matched healthy individuals (5.3±4.1% vs. 3.4±1.7%, P=0.028; 7.1±4.4% vs. 3.8±2.3%, P=0.001). Whereas MF patients' naïve T cells harbored an increased number of cells co-expressing CD8+/PD-1+ (P=0.007), but not CD4+/PD-1+, their T central memory cells had a high proportion of cells co-expressing CD4+/PD-1+ and CD8+/PD-1+ (P<0.001; P<0.001). Similarly, a high proportion of circulating PD-1+ T effector memory cells (P<0.001; P<0.001), and T effector cells (P=0.013; P<0.001) was found in MF patients compared to the same cell subsets in healthy age-matched individuals. The proportions of PD-1+ T cells significantly correlated with LDH level and DIPSS score (CD4+ T cells), monocyte count (CD8+ T cells), and total leukocyte count and spleen size (both subsets). Remarkably, the percentage of PD-1+ cells within naïve and central memory CD8+ T cell populations was significantly higher in MF patients with circulating blasts (P=0.036). To determine the effects of ruxolitinib administration, we performed repeated flow cytometry analyses on MF patients' T cells prior to and during treatment (median duration: 4.3 years). Overall, no significant change in PD-1 expression levels in any of the different T cell subsets was detected over the entire treatment period. However, a significant reduction in percentage of cells co-expressing CD4+/PD-1+ and CD8+/ PD-1+ compared to treatment baseline (4.4±0.4% vs. 7.6±2.0%, P=0.011; 6.3±0.6% vs. 10.4±2.7%, P=0.021) was found in patients whose spleen size was reduced after 6 months of treatment. Conclusions: In patients with MF, circulating T cells express high levels of PD-1. While not restricted to a particular stage of T cell differentiation, the correlation between PD-1-expressing T cells and distinct clinical parameters suggests that increased PD-1 levels might induce immune exhaustion in T cell subsets in different ways. Although ruxolitinib significantly inhibits the JAK1/2 signaling pathway in a variety of hematopoietic cells, thereby lowering cytokine/chemokine levels in almost all MF patients, treatment with ruxolitinib did not affect PD-1 expression nor did it alter its distribution among the T cell subsets. Yet, the proportion of PD-1-expressing CD4+ and CD8+ cells was markedly reduced in patients who experienced a superior response to ruxolitinib as assessed by significant spleen size reduction. How disease burden and MF microenvironment affect PD-1 expression in T cells of patients with MF warrants further investigation. Disclosures Verstovsek: Incyte: Consultancy; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees; Italfarmaco: Membership on an entity's Board of Directors or advisory committees.

scholarly journals Ecto-5′-Nucleotidase (CD73) Regulates the Survival of CD8+ T Cells

2021 ◽  
Vol 9 ◽  
Author(s):  
Mariana V. Rosemblatt ◽  
Brian Parra-Tello ◽  
Pedro Briceño ◽  
Elizabeth Rivas-Yáñez ◽  
Suat Tucer ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Interleukin 2 ◽  
Cd8 T Cell ◽  
Antigenic Stimulation ◽  
T Cell Subsets ◽  
Limited Information ◽  
Α Chain ◽  
The Impact

Ecto-5′-nucleotidase (CD73) is an enzyme present on the surface of tumor cells whose primary described function is the production of extracellular adenosine. Due to the immunosuppressive properties of adenosine, CD73 is being investigated as a target for new antitumor therapies. We and others have described that CD73 is present at the surface of different CD8+ T cell subsets. Nonetheless, there is limited information as to whether CD73 affects CD8+ T cell proliferation and survival. In this study, we assessed the impact of CD73 deficiency on CD8+ T cells by analyzing their proliferation and survival in antigenic and homeostatic conditions. Results obtained from adoptive transfer experiments demonstrate a paradoxical role of CD73. On one side, it favors the expression of interleukin-7 receptor α chain on CD8+ T cells and their homeostatic survival; on the other side, it reduces the survival of activated CD8+ T cells under antigenic stimulation. Also, upon in vitro antigenic stimulation, CD73 decreases the expression of interleukin-2 receptor α chain and the anti-apoptotic molecule Bcl-2, findings that may explain the reduced CD8+ T cell survival observed in this condition. These results indicate that CD73 has a dual effect on CD8+ T cells depending on whether they are subject to an antigenic or homeostatic stimulus, and thus, special attention should be given to these aspects when considering CD73 blockade in the design of novel antitumor therapies.

PD-L1/CD80 and PD-L1/PD-1 Signaling Reciprocally Regulate Alloreactive CD8+ T Cell Glycolysis, Proliferation, Apoptosis and Gvhd-Inducing Capacity

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4282-4282 ◽  
Author(s):  
Kaniel M. Cassady ◽  
Jian Zhou ◽  
Art Riggs ◽  
Defu Zeng
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Acute Gvhd ◽  
Cd8 T Cell ◽  
Cd4 T Cell ◽  
Glycolytic Flux ◽  
Widespread Application ◽  
Proliferation And Apoptosis ◽  
The Impact

Abstract Graft versus host disease (GVHD) remains the major obstacle for widespread application of allogeneic hematopoietic cell transplantation (HCT), a curative therapy for hematological malignancies. We and others have reported that while sorted CD4+ T cells induce severe acute GVHD, the same numbers of CD8+ T cells induce no acute GVHD. CD8+ T cells can facilitate donor cell engraftment and mediate graft versus leukemia (GVL) effect in the absence of GVHD, but the mechanisms remain largely unknown. Programmed death-ligand 1 (PD-L1) interacts with both CD80 and PD-1. We have recently reported that simultaneous PD-L1/CD80 and PD-L1/PD-1 signaling augments activated alloreactive CD4+ T cell proliferation and apoptosis and ameliorates acute GVHD. However, the impact of this PD-L1-mediated signaling on alloreactive CD8+ T cells has not been investigated. In addition, T cell glycolytic metabolism has been recently reported to be able to regulate acute GVHD, and PD-L1/PD-1 signaling inhibits CD4+ T cell glycolytic flux, but how PD-L1/CD80 modulates T cell metabolism remains unstudied. In the current studies, we evaluated the role of PD-L1/CD80 and PD-L1/PD-1 signaling on alloreactive CD8+ T cell glycolysis, proliferation, apoptosis and GVHD-inducing capacity, using a MHC-mismatched murine HCT model of C57BL/6 (H-2b) donor to BABL/c recipient (H-2d). We have observed the following early (3-5 days) after HCT: 1) In wild-type (WT) recipients, PD-1-/- CD8+ T cells significantly upregulate expression of Glucose Transporter I (Glut1) and exhibit much higher rates of glycolytic flux; PD-1-/- CD8+ T cells also show markedly enhanced proliferation and reduced apoptosis as well as up-regulation of gut tissue homing and chemokine receptors (i.e. α4β7 and CCR9) and induce lethal GVHD, as compared to WT CD8+ T cells that induce little signs of GVHD. 2) In PD-L1-/- recipients, PD-1-/- CD8+ T cells reduce expression of Glut1 and no longer exhibit enhanced glycolytic flux or reduced apoptosis; PD-1-/- CD8+ T cells transplanted into PD-L1-/- recipients also induce little GVHD, similar to WT CD8+ T cells. 3) After injection of anti-PD-L1 mAb (clone 43H12) that specifically blocks PD-L1/CD80 interaction and preserves PD-L1/PD-1 interaction, WT CD8+ T cells in WT recipients show drastically reduced expansion, as compared to control recipients treated with rat-IgG. Blockade of PD-L1/CD80 interaction reduces phosphorylation of key elements in the TCR signaling cascade and CD28 co-stimulatory pathway including ZAP-70, AKT, mTOR and rpS6. Taken together, these studies indicate that 1) PD-L1/CD80 signaling alone augments alloreactive CD8+ T cell expansion and GVHD-inducing capacity; 2) PD-L1/CD80 and PD-L1/PD-1 signaling reciprocally regulate CD8+ T cell glycolysis, proliferation, and apoptosis as well as their GVHD-inducing capacity, and a balance of the two signaling pathways would be required to allow donor CD8+ T cells to facilitate engraftment and mediate GVL effect without causing GVHD. This work was supported by Institutional Funds of The Beckman Research Institute of City of Hope. Disclosures No relevant conflicts of interest to declare.

Striking Clinical, Molecular and Immunological Outcomes in Non-Human Primate Hematopoietic Stem Cell Transplantation Using a Novel OX40L Blockade Agent, KY1005, Combined with Rapamycin

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3341-3341
Author(s):  
Victor Tkachev ◽  
Scott N. Furlan ◽  
Ben Watkins ◽  
Betty Zheng ◽  
Daniel Hunt ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Research Funding ◽  
Cd8 T Cell ◽  
Effector Memory ◽  
T Cell Proliferation ◽  
Hematopoietic Stem ◽  
Free Survival ◽  
The Impact

Abstract While calcineurin inhibition (CNI)-based strategies remain the mainstay for GVHD prevention, CNI are notoriously antagonistic to immune tolerance induction. Rapamycin (Rapa) has been shown to be more pro-tolerogenic; however, the best agents to combine with Rapa are still undetermined, and it remains a second-line GVHD prevention strategy without clear superiority over CNI. Finding tolerogenic partners for Rapa, therefore, represents a critical unmet need in the field. Of the possible partners for Rapa, the OX40/OX40L pathway represents an important target. OX40 is a costimulatory receptor expressed on activated human T cells, which, upon interaction with OX40L delivers activation signals to conventional T cells (Tconv) promoting their proliferation, survival and clonal expansion. Notably, these same OX40/OX40L signals may either inhibit or promote Treg functions, depending on context, suggesting that blockade of this pathway may simultaneously control Tconv activation while permitting Treg homeostasis. During GVHD in non-human primates (NHP), we found OX40L upregulation on myeloid dendritic cells and OX40 upregulation on activated T cells in recipients treated with multiple immunosuppressive agents, including Rapa (Fig 1). These data provided strong rationale for testing KY1005, a novel human monoclonal antibody that binds to OX40L and blocks its interaction with OX40, as a potential partner with Rapa. We tested the outcomes of prophylactic blockade of this pathway on NHP GVHD, using KY1005 alone and in combination with Rapa. These experiments utilized our previously published NHP GVHD model, in which GVHD is studied after T cell-replete haplo-identical HCT. KY1005 was dosed at 10mg/kg weekly from days -2ˆ+54 and Rapa was continued through Day +100. Prophylaxis with KY1005 alone provided initial evidence for its in vivo activity, with control of CD4>CD8 T cell proliferation and mitigation of the expansion of CD4>CD8 T effector/memory cells. Consistent with the partial control of T cell activation, these recipients demonstrated improved GVHD-free survival versus unprophylaxed controls, but disease ultimately broke through (Median Survival Time (MST) = 19.5 days with KY1005 (n=4) compared to 8 days in unprophylaxed recipients (n= 10, Fig 2)). We next investigated the impact of OX40L blockade + Rapa. We have published that Rapa as a monotherapy minimally controlled both immunologic and clinical disease, with an MST = 14 days (n=6). Combined prophylaxis was striking: recipients given KY1005+Rapa (n=5) maintained robust health throughout the entire experiment (MST >100d), and demonstrated high levels of donor T cell chimerism (86 +/- 3% at Day 100), rapid hematopoietic reconstitution, and had a terminal GVHD Grade of 0, compared to a Grade of III-IV in both KY1005- and Rapa-monotherapy cohorts. Immunologic analysis demonstrated synergistic control of both CD4 and CD8 T cell proliferation, restoring it to the level observed during autologous immune reconstitution, and resulting in a concomitant abrogation of CD4 and CD8 memory/effector expansion while preserving T cells with a na•ve phenotype. In striking contrast to the inhibition of Tconv activation by KY1005+Rapa, recipients of dual therapy demonstrated intact Treg reconstitution post-HCT, which resulted in a favorable Treg:Tconv ratio of 5.4 vs 1.4:100 in KY1005+Rapa treated compared to untreated recipients (p < 0.05). Transcriptomic analysis confirmed the unique immunologic state conferred by KY1005+Rapa on purified T cells, with gene arrays from these recipients demonstrating separation from all other transplant cohorts in Principal Component space (Figure 3A) and Class Neighbor Analysis identifying unique expression modules that tracked with KY1005 + Rapa prophylaxis (Figure 3B red and blue boxes). These results underscore the critical role of OX40/OX40L signaling in the development of GVHD and demonstrate the striking control of GVHD in KY1005+Rapa recipients. They represent the first demonstration of uniform, long-term GVHD-free survival in the primate model of high-risk haplo-identical HCT, and the first therapeutic strategy that simultaneously controls Tconv activation while supporting Treg homeostasis in this model. They suggest that OX40L blockade + Rapa is a novel, evidence-based combinatorial strategy to control GVHD that is an exceptional candidate regimen for clinical translation. Disclosures Tkachev: Kymab Ltd: Patents & Royalties: US Patent 9,382,325, Research Funding. Casson:Kymab Ltd: Employment. Kirby:Kymab Ltd: Employment, Patents & Royalties: US Patent 9,382,325. Bland-Ward:Kymab Ltd: Employment, Patents & Royalties: US Patent 9,382,325. Kean:Juno Therapeutics, Inc: Research Funding.

Expression of Immune Memory Markers CD8 α α and Interleukin−7 Receptor on CD8+ T Cell Subsets among HIV−1 Infected Patients.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1256-1256
Author(s):  
Jean Pierre Routy ◽  
Francois Mercier ◽  
Ahmed Galal ◽  
Med-Rachid Boulassel
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Activation ◽  
Cd8 T Cell ◽  
Central Memory ◽  
T Cell Subsets ◽  
Immune Memory ◽  
Effector Memory ◽  
Activation Markers ◽  
Hiv 1

Abstract Evidence from animal models suggests that the expression of CD8α α homodimer on CD8+ T-cells plays a key role in the generation of long-lived memory cells. However, very little information is available in the human clinical setting. Here, we examined immunophenotypic patterns of CD8+ T-cell subsets expressing CD8α α with other markers involved in generating and maintaining memory cells such as interleukin-7 receptor (IL-7Rα ) and circulating levels of IL-7 and IL-15, in three well-defined groups of human immunodeficiency virus-1 (HIV-1)-infected individuals including aviremic (n=15), viremic (n=31) and slow-progressor (n=15). In addition, immunophenotypic patterns were correlated with immune activation markers (CD38/HLA-DR), which are known to be an important factor in HIV-1 disease pathogenesis. Cell-surface expression of CD8α α , IL-7Rα and CD38/HLA-DR on CD8+ naïve, central memory, pre-terminal and terminal effector memory T-cells was measured by eight-color flow cytometry on freshly peripheral blood samples. IL-7 and IL-15 levels were measured by ELISA and viral loads were assessed by PCR. Group differences in the CD8+ T-cell subsets expressing each antigen tested were evaluated using the unpaired nonparametric Mann Whitney U test. Correlations were determined by Spearman’s correlation tests. Compared to slow-progressor subjects, expression of CD8α α was significantly reduced in aviremic and viremic patients and this reduction occurred mainly within naïve and central memory T-cell subsets and not in effector memory compartments. In contrast, persistent antigenemia in viremic patients appeared to lead to IL-7Rα loss mainly on central and effector memory subsets and not on naive T-cells. Compared to aviremic and viremic patients, slow-progressor subjects had lower levels of circulating IL-7, normal levels of IL-15, CD8α α and IL-7Rα , and reduced activated T-cells. Overall, expression of CD8α α was not significantly related to IL-7Rα although negative associations were evidenced within all CD8+ T-cell subsets. However, in viremic patients, naïve and central memory cell subsets expressing CD8α α were positively correlated with viral load but not with CD8+ T-cell subsets expressing immune activation markers. Together, these results provide new insights into the role of CD8α α /IL-7Rα along with immune activation markers in maintaining memory populations during HIV-1 infection. The inter-relationships between these immune memory markers require further investigations, which may help understanding the mechanisms of antiviral control.

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