scholarly journals Inosine is an alternative carbon supply that supports effector T cell proliferation and antitumor function under glucose restriction

2019 ◽  
Author(s):  
Tingting Wang ◽  
JN Rashida Gnanaprakasam ◽  
Xuyong Chen ◽  
Siwen Kang ◽  
Xuequn Xu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Adaptive Immune System ◽  
Immune Checkpoint Blockade ◽  
Effector T Cells ◽  
Immune Functions ◽  
Carbon Supply ◽  
Wide Range ◽  
Robust Adaptive

AbstractT cells undergo a characteristic metabolic rewiring that fulfills the dramatically increased bioenergetic, biosynthetic, and redox demands following antigen stimulation. A robust adaptive immune system requires effector T cells to respond and adapt to fluctuations in environmental nutrient levels imposed by infectious and inflammatory sites in different tissues. Inevitably, such responsiveness and adaptation reflect metabolic plasticity, allowing T cells to elicit immune functions by using a wide range of nutrient substrates. Here, we show that effector T cells utilize inosine, as an alternative substrate, to support cell growth and function in the absence of glucose. T cells metabolize inosine into hypoxanthine and phosphorylated ribose by purine nucleoside phosphorylase (PNP). Using Stable Isotope-Resolved Metabolomics (SIRM), we demonstrated that ribose moiety of inosine can enter into central metabolic pathways to provide ATP and biosynthetic precursors. Accordingly, the dependence of T cells on extracellular glucose for growth and effector functions can be relieved by inosine. On the other hand, cancer cells display diverse capacity to utilize inosine as a carbon resource. Moreover, the supplement of inosine enhances the anti-tumor efficacy of immune-checkpoint blockade or adoptive T cell transfer, reflecting the capability of inosine in relieving tumor-imposed metabolic restrictions on T cells in vivo.

scholarly journals H-2 restriction of virus-specific T-cell-mediated effector functions in vivo. II. Adoptive transfer of delayed-type hypersensitivity to murine lymphocytic choriomeningits virus is restriced by the K and D region of H-2.

1976 ◽  
Vol 144 (3) ◽  
pp. 776-787 ◽  
Author(s):  
R M Zinkernagel
Keyword(s):  
T Cells ◽  
T Cell ◽  
Adoptive Transfer ◽  
Gamma Globulin ◽  
Effector T Cells ◽  
Delayed Type Hypersensitivity ◽  
T Effector Cells ◽  
Immune Lymphocytes ◽  
D Region

In mice, primary footpad swelling after local infection with lymphocytic choriomeningitis virus (LCMV) and delayed-type hypersensitivity (DTH) adoptively transferred by LCMV immune lymphocytes are T-cell dependent. Nude mice do not develop primary footpad swelling, and T-cell depletion abrogates the capacity to transfer LCMV-specific DTH. Effector T cells involved in eliciting dose-dependent DTH are virus specific in that vaccinia virus-immune lymphocytes could not elicit DTH in LCMV-infected mice. The adoptive transfer of DTH is restricted to H-2K or H-2D compatible donor-recipient combinations. Distinct from the fowl-gamma-globulin DTH model, I-region compatibility is neither necessary nor alone sufficient. Whatever the mechanisms involved in this K- or D-region associated restriction in vivo, it most likely operates at the level of T-cell recognition of "altered self" coded in K or D. T cells associated with the I region (helper T cells and DTH-T cells to fowl-gamma-globulin) are specific for soluble, defined, and inert antigens. T cells associated with the K and D region (T cells cytotoxic in vitro and in vivo for acute LCMV-infected cells, DTH effector T cells, and anti-viral T cells) are specific for infectious, multiplying virus. The fact that T-cell specificity is differentially linked with the I region or with the K and D regions of H-2 may reflect the fundamental biological differences of these antigens. Although it cannot be excluded that separate functional subclasses of T-effector cells could have self-recognizers for different cell surface structures coded in I or K and D, it is more likely that the antigen parameters determine whether T cells are specific for "altered" I or "altered" K- or D-coded structures.

scholarly journals CD8+ T Cell–mediated Injury In Vivo Progresses in the Absence of Effector T Cells

2001 ◽  
Vol 194 (12) ◽  
pp. 1835-1846 ◽  
Author(s):  
Barbara A. Small ◽  
Sarah A. Dressel ◽  
Christopher W. Lawrence ◽  
Donald R. Drake ◽  
Mark H. Stoler ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tissue Injury ◽  
Cd8 T Cell ◽  
Effector T Cells ◽  
Type Ii ◽  
Pulmonary Injury ◽  
Alveolar Cells ◽  
Type Ii Alveolar Cells

Tissue injury is a common sequela of acute virus infection localized to a specific organ such as the lung. Tissue injury is an immediate consequence of infection with lytic viruses. It can also result from the direct destruction of infected cells by effector CD8+ T lymphocytes and indirectly through the action of the T cell–derived proinflammatory cytokines and recruited inflammatory cells on infected and uninfected tissue. We have examined CD8+ T cell–mediated pulmonary injury in a transgenic model in which adoptively transferred, virus-specific cytotoxic T lymphocytes (CTLs) produce lethal, progressive pulmonary injury in recipient mice expressing the viral target transgene exclusively in the lungs. We have found that over the 4–5 day course of the development of lethal pulmonary injury, the effector CTLs, while necessary for the induction of injury, are present only transiently (24–48 h) in the lung. We provide evidence that the target of the antiviral CD8+ T cells, the transgene expressing type II alveolar cells, are not immediately destroyed by the effector T cells. Rather, after T cell–target interaction, the type II alveolar cells are stimulated to produce the chemokine monocyte chemoattractant protein 1. These results reinforce the concept that, in vivo, the cellular targets of specific CTLs may participate directly in the development of progressive tissue injury by activating in response to interaction with the T cells and producing proinflammatory mediators without sustained in vivo activation of CD8+ T cell effectors.

T Cells Genetically Modified to Be CD19-Specific with Improved Potential for Trafficking and Activation.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1748-1748
Author(s):  
Zaid Al-Kadhimi ◽  
Lisa Marie Serrano ◽  
Simon Olivares ◽  
Sergio Gonzalez ◽  
Timothy Pfeiffer ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cytokine Production ◽  
Genetically Modified ◽  
Cell Receptor ◽  
Effector T Cells ◽  
Concentration Gradients ◽  
Chimeric Immunoreceptor

Abstract The safety and feasibility of adoptive immunotherapy using ex vivo-expanded differentiated human effector T cells that express tumor-specific chimeric receptors are being evaluated in clinical trials. Typically, these T cells are CCR7neg and bear a T-cell receptor of unknown specificity. To improve the therapeutic potential of genetically engineered T cells in general, and CD19-specific T cells in particular, strategies are needed to improve their ability traffic to sites of residual/macroscopic disease where infused T cells can be specifically activated for proliferation, cytokine secretion, and tumor-lysis. To accomplish these goals we have generated a selection process that uses genetically modified T cells, expressing influenza A matrix protein 1 (MP1) or CMV pp65, to act as antigen presenting cells (T-APC) in order to expand autologous viral-specific T cells in vitro and in vivo. The viral-specific effector T cells can then be genetically modified with a CD19-specific chimeric immunoreceptor (CD19R), which recognizes CD19 on malignant B cells, independent of MHC. By using these viral-specific T cells as a platform for the introduction of CD19R, we now demonstrate that bi-specific T cells express the chemokine receptor CCR7, which is implicated in the trafficking of T cells to lymph nodes. We demonstrate that this chemokine receptor functions to directionally chemotax the genetically modified bi-specific T-cells along concentration gradients of CCL19 or CCL21. We further demonstrate that both the endogenous and introduced chimeric immunoreceptor continue to function in CCR7+ bi-specific T cells. Indeed, the bi-specific T cells are capable of augmented cytokine production and proliferation upon docking with both CD19 and MP1 antigens, compared with these same T cells interacting with either CD19 or MP1 alone. This enhanced activation is an explanation for the enhanced in vivo anti-tumor activity demonstrated by bi-specific T-cells when stimulated with MP1+ T-APC in treating CD19+ lymphoma in NOD/scid mice. An advantage of this methodology is that the CCR7+ bi-specific T cells and T-APC can be genetically modified and expanded in compliance with current good manufacturing practice (cGMP) for 2nd generation Phase I/II clinical trials to test their ability to traffic to sites of lymphoma providing potent regional/local T-cell activation. Legend: (A) CCR7+ viral- and CD19-bi-specific T cells migrate along recombinant CCL19 and CCL21 concentration gradients, whereas CCR7neg CD19-specific T cells do not. (B) Stimulation of both introduced chimeric immunoreceptor and endogenous T-cell receptor on CD19- and MP1- bi-specific T-cells, using artificial APC, results in augmented cytokine production. Figure Figure

Tumor-Targeted Human CD4+ CD25hi Regulatory T Cells Effectively Inhibit T Cell –mediated Rejection of CD19+ Tumors in An in Vivo xenotransplant Tumor Model

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3901-3901
Author(s):  
James Lee ◽  
Michel Sadelain ◽  
Renier J. Brentjens
Keyword(s):  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
B Cell ◽  
Clinical Setting ◽  
Effector T Cells ◽  
Effector T Cell ◽  
Human T Cells ◽  
Anti Tumor Activity

Abstract The genetic targeting of human T cells to selected tumor antigens offers a novel means to investigate human immunobiology and treat cancer. T cells may be genetically modified to target specific antigens through the introduction of genes encoding chimeric antigen receptors (CARs). We have previously demonstrated that human T cells targeted in this manner to the CD19 antigen, expressed on normal B cells as well as most B cell tumors, eradicate systemic human CD19+ B cell malignancies in SCID-Beige mice. However, in the clinical setting, the anti-tumor efficacy of these T cells may be impaired by endogenous suppressive elements of the host immune system, including CD4+ CD25hi Foxp3+ regulatory T cells (Tregs). Significantly, Tregs are often increased in the blood and infiltrate the tumor of cancer patients which has been correlated with poor patient outcome and ineffective anti-tumor immunity. In order to study the in vivo impact of Tregs on adoptive therapy with CD19 targeted effector T cells, we developed a murine model wherein human Tregs, similarly targeted to the tumor, are infused prior to adoptive transfer of targeted cytotoxic T cells. To do so, we initially isolated natural Tregs from healthy donor peripheral blood mononuclear cells. Isolated Tregs were subsequently modified to express CARs through retroviral gene transfer. Subsequently, CAR+ Tregs were rapidly expanded either by activation on NIH-3T3 fibroblasts modified to express CD19 and the CD80 costimulatory ligand (3T3(CD19/CD80)), or non-specifically using CD3/CD28 antibodycoated magnetic beads. Expanded CAR+ Tregs exhibited potent suppressive function in vitro inhibiting both effector T cell proliferation as well as cytotoxicity. In vivo, CAR+ Tregs specifically traffic to established tumor in SCID-Beige mice. Significantly, injection of CD19-targeted Tregs into SCID-Beige mice bearing established human CD19+ tumors at 24 hours prior to infusion with CD19-targeted effector T cells, completely abrogated effector T cell function even at Treg:Teff ratios as low as 1:8. We further found that full suppression was dependant both on Treg localization to the tumor site as well as in vivo activation through the CAR. Finally, we show that a pre-conditioning regimen with low-dose cyclophosphamide, which failed to eradicate tumor, was able to reverse the CAR+ Treg mediated inhibition and restore the anti-tumor activity by the targeted effector T cells. In conclusion, we have developed a robust model ideally suited to the study of in vivo Treg-Teff interactions. Furthermore, the data generated from this model to date have significant implications with respect to the application of adoptive T cell therapies in the clinical setting. Namely, the presence of endogenous Tregs at the site of tumor is likely to significantly compromise the anti-tumor activity of adoptively transferred tumor targeted T cells. This inhibition may be reversed by preconditioning regimens designed to eradicate endogenous Tregs. The findings presented here should be considered in the design of future clinical trials utilizing T cell-based adoptive therapies of cancer.

Inhibition of Histone Methylation Arrests Ongoing Graft-Versus-Host Diseases in Mice by Selectively Inducing Apoptosis of Alloreactive Effector T Cells

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 820-820
Author(s):  
Shan He ◽  
Jina Wang ◽  
Koji Kato ◽  
Fang Xie ◽  
Sooryanarayana Varambally ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Histone Methylation ◽  
Effector T Cells ◽  
Hematopoietic Stem ◽  
Graft Versus Host ◽  
Alloreactive T Cells ◽  
Novel Approaches ◽  
In Vivo Administration

Abstract Abstract 820 Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment option for patients with hematological malignancies. However, its success is limited by life-threatening graft-versus-host disease (GVHD). Novel approaches are needed to control GVHD. Recent studies have shown the importance of histone methylation in regulating the expression of genes associated with effector T cell differentiation and proliferation. Using several mouse models of allo-HSCT, we report that in vivo administration of the histone methylation inhibitor 3-Deazaneplanocin A (DZNep) arrested ongoing GVHD while preserving graft-versus-leukemia activity (GVL). To assess the therapeutic effect of pharmacologic modulation of histone methylation on GVHD, we administered DZNep to BALB/c mice receiving major histocompatibility-mismatched C57BL/6 mouse T cells 7 days after transplantation, in which GVHD had been fully established. Notably, injection of 12 doses of DZNep controlled the disease in these recipients, with approximately 80% of them surviving long-term without significant clinical signs of GVHD. We found that in vivo administration of DZNep caused selective apoptosis in alloantigen-activated T cells, but did not impair the generation of effector T cells that produced inflammatory cytokines (e.g., TNF-α, IFN-γ and IL-17) and cytotoxic molecules (e.g., granzyme B and Fas ligand). As a result, alloreactive T cells retained potent GVL activity, leading to improved overall survival of the recipients challenged by leukemic cells. These data suggest that DZNep-mediated inhibition of GVHD may be accounted for by reduced number of alloreactive effector T cells. In vitro culture assays showed that DZNep treatment induced apoptosis in T cells activated by anti-CD3/CD28 antibodies but not in naive T cells stimulated by IL-2 or IL-7. This effect was associated with DZNep's ability to selectively reduce trimethylation of histone H3 lysine 27 (H3K27), deplete the histone methyltranferase Ezh2 that specifically catalyzes trimethylation of H3K27, and activate Ezh2-repressed pro-apoptotic gene Bim. Inactivation of Bim partially protected alloreactive T cells from DZNep-mediated apoptosis. Importantly, unlike DNA methylation inhibitors, inhibition of histone methylation by DZNep had no toxicities to hematopoietic cells or impairment on the reconstitution of hematopoiesis and thymopoiesis. Our findings indicate that modulation of histone methylation may have significant implications in the development of novel approaches to treat established GVHD and other T cell-mediated inflammatory disorders in a broad context. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Fucoidan-Supplemented Diet Potentiates Immune Checkpoint Blockage by Enhancing Antitumor Immunity

2021 ◽  
Vol 9 ◽  
Author(s):  
Juan Yang ◽  
Xianzhi Yang ◽  
Wenfeng Pan ◽  
Mingshuo Wang ◽  
Yuxiong Lu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cancer Progression ◽  
T Cell Activation ◽  
Immune Checkpoint ◽  
Cell Activation ◽  
Synergistic Effects ◽  
Immune Checkpoint Blockade ◽  
Stat Pathway

Immune checkpoint blockade (ICB) therapies such as PD-1 antibodies have produced significant clinical responses in treating a variety of human malignancies, yet only a subset of cancer patients benefit from such therapy. To improve the ICB efficacy, combinations with additional therapeutics were under intensive investigation. Recently, special dietary compositions that can lower the cancer risk or inhibit cancer progression have drawn significant attention, although few were reported to show synergistic effects with ICB therapies. Interestingly, Fucoidan is naturally derived from edible brown algae and exhibits antitumor and immunomodulatory activities. Here we discover that fucoidan-supplemented diet significantly improves the antitumor activities of PD-1 antibodies in vivo. Specifically, fucoidan as a dietary ingredient strongly inhibits tumor growth when co-administrated with PD-1 antibodies, which effects can be further strengthened when fucoidan is applied before PD-1 treatments. Immune analysis revealed that fucoidan consistently promotes the activation of tumor-infiltrating CD8+ T cells, which support the evident synergies with ICB therapies. RNAseq analysis suggested that the JAK-STAT pathway is critical for fucoidan to enhance the effector function of CD8+ T cells, which could be otherwise attenuated by disruption of the T-cell receptor (TCR)/CD3 complex on the cell surface. Mechanistically, fucoidan interacts with this complex and augments TCR-mediated signaling that cooperate with the JAK-STAT pathway to stimulate T cell activation. Taken together, we demonstrated that fucoidan is a promising dietary supplement combined with ICB therapies to treat malignancies, and dissected an underappreciated mechanism for fucoidan-elicited immunomodulatory effects in cancer.

scholarly journals Novel Multi-Target Immunosuppressive Approach for Treatment of Severe Aplastic Anemia

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3611-3611 ◽  
Author(s):  
Kyle Blaine Russell ◽  
Brandon P Theall ◽  
Lisandra Hernandez ◽  
Hannah M Wavering ◽  
Vesna Jurecic ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
Autoimmune Diseases ◽  
Aplastic Anemia ◽  
Effector T Cells ◽  
Prolonged Treatment ◽  
Effector T Cell ◽  
New Therapy

Abstract Aplastic Anemia (AA) is an immune-mediated form of acquired bone marrow failure (BMF), which is life-threatening in its severe form (SAA). Fundamental pathological features of AA include development and expansion of auto-reactive effector T cells, effector T cell-mediated apoptosis of all hematopoietic cells (including progenitors and hematopoietic stem cells (HSCs)), BM aplasia, pancytopenia, depletion of HSCs, and severe reduction and functional impairment of regulatory T cells (Tregs). Current standard treatments for AA include: (1) immuno-suppressive therapy (IST) with cyclosporine A (CyA) and anti-thymocyte globulin (ATG) which targets all T cells, and (2) allogeneic or matched unrelated donor BM transplant. While IST remains a standard treatment modality, it is not very effective in treating already ongoing and relapsed AA or SAA. There is really no effective therapy for patients with refractory and relapsed AA who are ineligible for BMT. Among different pathophysiological features of AA, IST targets only the effector T cells, and is much more effective in the early than later stages of AA. Moreover, the combination of IST with other immunosuppressive agents (mycophenolate mofetil, sirolimus etc.) or growth factors does not improve the response or survival of AA patients. Since the incidence of AA is on the rise, there is an urgent need for more efficient new therapies that can attenuate the progression and severity of AA in patients with refractory and relapsed AA who are waiting for or are not candidates for BMT. The complex immune and hematological pathophysiology of AA requires new multipurpose treatment approaches. Accumulating evidence shows that β2 integrin CD11b/CD18 (Mac-1) negatively regulates T cell responses and activation, attenuates inflammation, and facilitates the maintenance of tolerance to self-antigens. For example, activated Mac-1 significantly reduces the T cell-activating capacity of dendritic cells (DCs), represses DC cross-priming of cytotoxic T cells, negatively regulates NK cell activation and function, suppresses differentiation of Th17 T cells which are associated with AA and other autoimmune diseases, ameliorates experimental autoimmune hepatitis, and negatively regulates BCR signaling and maintains autoreactive B cell tolerance. For that reason, Mac-1 is an attractive molecular target for new immune-modulating therapies of autoimmune diseases. Using the clinically relevant mouse SAA model we have evaluated the therapeutic efficacy of Leukadherins (LA1-LA3), novel small molecule agonists and activators of Mac-1, as a novel multipurpose immunosuppressive and anti-inflammatory approach to treat AA. The present studies have demonstrated that administration of LA1 safely and significantly (1) suppresses expansion of effector T cells, (2) decreases effector T cell-mediated apoptosis of target BM cells, (2) reduces BM aplasia, (3) minimalizes the loss of HSCs and progenitors, and (4) attenuates the severity of SAA. Furthermore, prolonged treatment of developing SAA with LA1 has therapeutic effects since it not only attenuates the progression and severity of SAA, but also converts otherwise fatal SAA into a survivable disease in mouse SAA models. To begin to address mechanism for these findings we found that LA1 treatment significantly reduces the antigen presenting capacity and T cell activating capacity of DCs. Importantly, in vivo LA1 treatment significantly increases the population of regulatory T cells (Tregs) which may also contribute to the above effects of LA1 on SAA. Simultaneous targeting of multiple pathophysiological features of AA underscores the clinically relevant potential of LA1 treatment as a novel promising multi-target immunosuppressive therapy that can safely and efficiently attenuate the severity of AA and reduce the need for BMT. We are also further evaluating the potential of LA1 treatment combined with IST or in vivo Treg expansion approaches (low dose rIL-2 therapy) to safely and more effectively attenuate the progression and severity of AA in pre-clinical mouse SAA models. These studies will provide an important platform for further translational and clinical testing of LAs as: (1) New therapy to manage ongoing AA in patients who are not responding to IST and are not candidates for BMT, (2) New therapy for relapsed AA, and/or (3) Adjuvant therapy for AA patients who are undergoing IST and are awaiting BM transplant. Disclosures Levy: Allergan: Consultancy.

scholarly journals P06.15 Highly multiplexed, single-cell functional proteomics of CAR-T products enables more predictive product characterization, cell manufacturing optimization, and cellular biomarkers across product types

2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A48.1-A48
Author(s):  
D Liu ◽  
P Paczkowski ◽  
S MacKay ◽  
J Zhou
Keyword(s):  
T Cells ◽  
T Cell ◽  
Single Cell ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Manufacturing Optimization ◽  
Wide Range ◽  
Car T ◽  
Specific Stimulation

Chimeric antigen receptor (CAR) T cell therapy has already paved the way for successful immunotherapies to fight against liquid tumors and is quickly expanding to solid tumors. Nevertheless, the biggest challenges are how to evaluate the quality of CAR-T cells and how to predict their in vivo behaviors once reinfused into a patient. In this report, we review single-cell polyfunctional profiling results obtained from several different sets of pre-infusion CAR-T samples, including CD19 CAR-T products from Novartis and Kite Pharma (Gilead), GoCAR-T cell products targeting Prostate Stem Cell Antigen from Bellicum, bispecific CD19/22 CAR-T cells from the NIH, trimeric APRIL-based CAR-T cells targeting both BCMA and TACI from MGH and CAR-T cells targeting glypican 3 in hepatocellular carcinoma from NIH. In each case, CD4+ and CD8+ CAR-T cells were stimulated and subsequently analyzed at a single-cell level using IsoPlexis’ IsoCode proteomic chips. Our single-cell data revealed highly polyfunctional and heterogeneous responses across each cohorts. The polyfunctional strength index (PSI) of the pre-infused CAR-T products is significantly associated with the clinical outcome of the patients after receiving the treatment, as well as post-infusion grade 3+ CRS. The CAR-T cells secreted a wide range of cytokines/chemokines in response to antigen specific stimulation and a significant portion of the CAR-T cells were polyfunctional (2+cytokines/cell). These results highlight the potential benefits of single-cell proteomics to comprehensively understand how CAR-T products behave in response to antigen-specific stimulation. Analyzing the single-cell polyfunctionality of CAR-T profiles also provides a valuable quality check for optimizing the manufacturing process and a powerful tool for next generation biomarker developments.Disclosure InformationD. Liu: None. P. Paczkowski: None. S. MacKay: None. J. Zhou: None.

Impact of Regulatory T Cells on Antigen Specific T Cell Response Using Recombinant Chimeric T Cell Receptors In Vivo.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5475-5475
Author(s):  
David M. Kofler ◽  
Markus Chmielewski ◽  
Heike Koehler ◽  
Tobias Riet ◽  
Patrick Schmidt ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
Tumor Cells ◽  
T Cell Receptors ◽  
Cell Response ◽  
Effector T Cells ◽  
T Cell Response ◽  
Cell Receptors

Abstract Recombinant T cell receptors with defined specificity against tumor cells are a promising experimental approach in the elimination of residual leukemia and lymphoma cells. It is so far unresolved whether regulatory T cells with suppressor activities impair the efficiency of cytolytic T cells grafted with a recombinant immunoreceptor. The frequency of regulatory T cells is highly increased in tumor patients and their suppressive function seems to play a role in the fail of an autologous T cell response against the malignant cells. In this study we analyzed the antigen-triggered, specific activation of receptor grafted T cells in the presence or absence of regulatory CD4+CD25high T cells. CD3+ T cells were grafted with CEA-specific immunoreceptors containing the CD3-zeta signaling domain for T cell activation. Co-cultivation of receptor grafted effector T cells together with regulatory T cells repressed proliferation of the effector cells and decreased IL-2 secretion. Secretion of IFN-gamma and IL-10 was not impaired. Interestingly, the cytotoxicity of grafted effector T cells towards CEA-expressing tumor cells was not impaired by regulatory T cells in vitro. To evaluate the relevance in vivo, we used a Crl:CD1 Nu/Nu mouse model to assess growth of CEA+ tumor cells in the presence of receptor grafted effector T cells and of regulatory T cells. Mice inoculated with tumor cells together with CD3+ effector T cells without immunoreceptor and regulatory T cells developed earlier tumors with faster growth kinetics compared to mice that were inoculated with tumor cells, CD3+ T cells and CD4+CD25- control T cells. Using effector T cells that were equipped with a recombinant CEA-specific CD3-zeta immunoreceptor, 2 of 5 mice developed a tumor in the presence of regulatory T cells while none of the mice developed a tumor in the absence of regulatory T cells. Taken together, regulatory T cells obviously impair an antigen-specific, anti-tumor T cell attack in vivo. This seems to be due to repression of proliferation of the effector T cells and not to diminished cytotoxicity. These findings have major impact on the design of clinical studies involving adoptively transferred effector T cells.

Engraftment Fitness of Human Central Memory-Derived Effector CD8+ T Cells In Immunodeficient Mice

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1019-1019
Author(s):  
Xiuli Wang ◽  
Berger Carolina ◽  
Stanley R. Riddell ◽  
ChingLam W Wong ◽  
Stephen Forman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Adoptive Transfer ◽  
Tumor Response ◽  
Memory T Cells ◽  
Effector T Cells ◽  
Caspase Activity ◽  
Effector Cells ◽  
Nog Mice

Abstract Abstract 1019 Development of T cell products that have engineered specificity for CD19 has broad application to adoptive transfer therapy for B-lineage lymphoma and leukemia. Clinical studies have demonstrated the safety and feasibility of T cell transfer as a therapy for patients. But the potency of this strategy has proven challenging, primarily due to issues relating to a lack of persistence of the adoptively transferred cells in patients. The repertoire of memory T cells is heterogeneous with respect to phenotypic, functional, and epigenetic attributes. Memory T cells are divided into sub-populations of 1) effector memory (TEM) cells that distribute to tissue beds and exhibit immediate cytolytic effector functioning, and 2) central memory (TCM) cells that home to lymph nodes based on CD62L/CCR7 expression and are capable of extensive proliferative activity upon re-encountering antigen. Thus the cell-intrinsic programming of distinct memory T cell subtypes, such as TEM and TCM, likely dictate divergent fates of their derived effector cells. To address this important issue, a clear functional dichotomy between TCM- and TEM-derived CD8+ CTLs was recently delineated in a nonhuman primate model, where it was found that virus-specific CD8+ CTL clones derived from TCM, but not TEM precursors, establish persistent and functional memory following adoptive transfer. Here, we extended these studies to human effector T cells using CMV as antigen model system to investigate the engraftment of human CMVpp65-specific CD8+ effector T cells derived in vitro from either sort purified CD45RO+CD62L+ TCM or CD45RO+CD62L- TEM precursors in NOD/Scid IL-2RγCnull (NOG) mice. TCM-derived effector cells (TE(CM)) and TEM-derived effector cells (TE(EM)) were adoptively transferred (i.v) into NOG mice reconstituted with human IL-15 and T cell levels in circulation were evaluated at different time points by FACS. 20% CD8+ TE(CM) and 3% CD8+ TE(EM) were detected on day 14. Then after, engraftment of the CD8+ TE(CM) remained at a steady state of approx 2% of circulating mononuclear cells for 100 days while TE(EM) remained at or below the level of detection, indicating that TE(CM) were superior in their ability to engraft in response to IL-15 as compared to TE(EM) after adoptive transfer (P<0.05). The long-term (100 days) persisting CD8+ TE(CM), harvested from primary recipient mice were found to be capable of engrafting secondary recipients. TcR Vβ analysis of persisting cells demonstrated that CD8+ TE(CM) engraftment was polyclonal, suggesting that homeostatic engraftment fitness is a general feature of these cells. To delineate the mechanism(s) by which TE(CM) exhibit superior in vivo engraftment, TE(CM) and TE(EM) were first labeled with CFSE before in vivo administration. CFSE profiles appear that the TE(EM) proliferated more extensively than TE(CM) early after adoptive transfer as indicated by the percent of cells which diluted CFSE on day 9 (i.e., 80% vs. only 25%, respectively). However, using D2R cleavage as a measure of caspase activity as a surrogate for apoptosis, 5.8% of engrafting TE(CM) were positive for activated caspase activity compared to 31.6% of TE(EM), suggesting that in NOG mice both CD8+ TE(CM) and TE(EM) proliferate in response to IL-15 whereas TE(CM) are intrinsically resistant to caspase activation and apoptosis. We also evaluated the antigen specific responsiveness of engrafted cells. Weekly infusions of irradiated pp65+/A2+ LCL as antigen significantly augmented the levels of circulating CD8+ TE(CM) as compared to no antigen stimulation (P<0.05), whereas CD8+ TE(EM) did not respond to antigen challenge. Moreover, when CMVpp65 specific CD8+ TE(CM) or TE(EM) were infused into CMVpp65+ tumor bearing mice, tumor cells progressed in mice receiving TE(EM) at a rate similar to untreated control mice over a ten day observation period, whereas TE(CM) significantly controlled tumor progression (P<0.05), indicating that CD8+ TE(CM) but not TE(EM) are able to mediate an anti-tumor response. Together these studies confirm that human CD8+ effector T cells derived from TCM precursors are capable of persistence after infusion, can proliferate in in vivo in response to antigen, can mediate an anti-viral or anti tumor response, and are likely the preferred T cells for antigen specific anti-tumor adoptive T cell therapy . Disclosures: No relevant conflicts of interest to declare.

Sign in / Sign up

Export Citation Format

Share Document