Electroporation of Dicer-Substrate siRNA Duplexes Targeting Endogenous TCR Enhance Tumor Killing Activity of Wilms' Tumor 1 (WT1)-Specific TCR-Redirected Cytotoxic T Cells

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 813-813 ◽  
Author(s):  
Diana Campillo-Davo ◽  
Fumihiro Fujiki ◽  
Johan M.J. Van den Bergh ◽  
Evelien L. Smits ◽  
Haruo Sugiyama ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Wilms Tumor ◽  
Target Cells ◽  
Wild Type ◽  
Activation Markers ◽  
Killing Activity ◽  
Ifn Γ ◽  
Mrna Electroporation

Abstract In adoptive cellular immunotherapy, T cells can be genetically engineered to express a novel T-cell receptor (TCR) that recognizes a tumor-associated antigen. However, mispairing between transgene and endogenous TCR chains may result in a reduction of transgene TCR expression and potentially harmful off-target reactivities. Here, we sought to develop a novel clinically safe strategy to promote transgene expression of a Wilms' tumor 1 (WT1)-specific TCR by Dicer-substrate small interfering RNA (DsiRNA)-mediated silencing of the endogenous TCR, using a double electroporation protocol. First, we isolated and cloned an HLA-A*0201-restricted WT1 peptide-specific TCR derived from a leukemia patient who demonstrated clinical benefit after receiving a WT1-targeted DC vaccine. Next, we produced a codon-optimized TCR sequence from the wild-type TCR construct and both TCR mRNAs were generated by in vitro transcription. TCR expression levels were validated by electroporation of TCR-deficient Jurkat J76.7 cells stably transduced with CD8 and an NFAT-driven GFP reporter gene. TCR functionality was confirmed by high expression levels of GFP (70% GFP+cells) upon TCR signaling after co-culture with WT1 peptide-pulsed T2 cells. In order to suppress the translation of endogenous TCR mRNA in CD8+ T cells, DsiRNA duplexes were designed to specifically target the constant regions of wild-type TCR α- and β-chains, but not the codon-optimized TCR. We further developed a double electroporation protocol combining DsiRNA and TCR mRNA transfection in which DsiRNA electroporation was performed 24 hours prior to TCR mRNA electroporation. Our results show more than 2-fold increase in WT1-specific TCR expression by HLA-A2/WT1 tetramer staining after DsiRNA treatment as compared to TCR mRNA electroporation only. This specific TCR expression was maintained at least 5 days after TCR mRNA electroporation in resting peripheral blood CD8+ lymphocytes from healthy donors. The enhanced TCR expression in DsiRNA-transfected CD8+T cells was also correlated with an increase of epitope recognition as shown by interferon (IFN)-γ ELISpot. To determine the killing capacity of DsiRNA/TCR mRNA-transfected CD8+ T cells against epitope-bearing target cells, we performed a flow cytometry-based cytotoxicity assay using WT1 peptide-pulsed T2 cells. Specific cytotoxicity, which was already present in WT1 TCR-transfected cells, was significantly enhanced in TCR mRNA-electroporated T cells following suppression of the endogenous TCR expression by DsiRNA treatment. Accordingly, DsiRNA-treated TCR mRNA transfected CD8+T cells presented higher levels of CD137 and CD69 activation markers and secretion of cytokines (IFN-γ and tumor necrosis factor-α), granzyme B, and perforin upon TCR triggering as compared to the non-DsiRNA treated T cells. In summary, we show a marked enhancement of transgene WT1-specific TCR expression upon silencing of the endogenous TCR using DsiRNA electroporation prior to TCR mRNA electroporation. Importantly, this enhancement in TCR expression was correlated with a significant increase in WT1-specific CD8+ T-cell killing activity, expression of CD69 and CD137 activation markers and cytokine secretion after recognition of WT1 peptide-bearing target cells. These results pave the way for developing a clinically safer strategy for T cell-based adoptive immunotherapy of patients with WT1-expressing malignancies. Disclosures No relevant conflicts of interest to declare.

scholarly journals Generation of Human CD8 T Regulatory Cells by CD40 Ligand–activated Plasmacytoid Dendritic Cells

2002 ◽  
Vol 195 (6) ◽  
pp. 695-704 ◽  
Author(s):  
Michel Gilliet ◽  
Yong-Jun Liu
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Transforming Growth Factor ◽  
Cd8 T Cell ◽  
Cd40 Ligand ◽  
Plasmacytoid Dendritic Cells ◽  
Target Cells ◽  
Ifn Γ

Although CD8 T cell–mediated immunosuppression has been a well-known phenomenon during the last three decades, the nature of primary CD8 T suppressor cells and the mechanism underlying their generation remain enigmatic. We demonstrated that naive CD8 T cells primed with allogeneic CD40 ligand–activated plasmacytoid dendritic cells (DC)2 differentiated into CD8 T cells that displayed poor secondary proliferative and cytolytic responses. By contrast, naive CD8 T cells primed with allogeneic CD40 ligand–activated monocyte-derived DCs (DC1) differentiated into CD8 T cells, which proliferated to secondary stimulation and killed allogeneic target cells. Unlike DC1-primed CD8 T cells that produced large amounts of interferon (IFN)-γ upon restimulation, DC2-primed CD8 T cells produced significant amounts of interleukin (IL)-10, low IFN-γ, and no IL-4, IL-5, nor transforming growth factor (TGF)-β. The addition of anti–IL-10–neutralizing monoclonal antibodies during DC2 and CD8 T cell coculture, completely blocked the generation of IL-10–producing anergic CD8 T cells. IL-10–producing CD8 T cells strongly inhibit the allospecific proliferation of naive CD8 T cells to monocytes, and mature and immature DCs. This inhibition was mediated by IL-10, but not by TGF-β. IL-10–producing CD8 T cells could inhibit the bystander proliferation of naive CD8 T cells, provided that they were restimulated nearby to produce IL-10. IL-10–producing CD8 T cells could not inhibit the proliferation of DC1-preactivated effector T cells. This study demonstrates that IL-10–producing CD8 T cells are regulatory T cells, which provides a cellular basis for the phenomenon of CD8 T cell–mediated immunosuppression and suggests a role for plasmacytoid DC2 in immunological tolerance.

scholarly journals 720 CUE-102 selectively activates and expands WT1-specific T cells for the treatment of patients with WT1+ malignancies

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A749-A749
Author(s):  
Christie Zhang ◽  
Natasha Girgis ◽  
Zohra Merazga ◽  
Steven Hatfield ◽  
Alex Histed ◽  
...  
Keyword(s):  
T Cells ◽  
Transgenic Mice ◽  
Cd8 T Cells ◽  
Wilms Tumor ◽  
Interleukin 2 ◽  
Target Cells ◽  
Tolerability Profile ◽  
Activation Markers

BackgroundWilms' Tumor 1 (WT1) was ranked as the highest priority antigen for therapeutic targeting in an effort by the National Cancer Institute. Development of novel modalities targeting WT1 provide a significant opportunity to address high unmet medical need in WT1-positive malignancies, including AML, ovarian, endometrial, breast, lung, colorectal and pancreatic cancer. Leveraging the Immuno-STAT platform of targeted IL-2 therapies, and the ongoing development of CUE-101, CUE-102 is being developed as a novel therapeutic fusion protein to selectively activate tumor antigen-specific T cells to treat WT1-expressing cancers. CUE-102 consists of two human leukocyte antigen (HLA) molecules presenting a WT1 peptide, four affinity-attenuated human interleukin-2 (IL-2) molecules, and an effector attenuated human immunoglobulin G (IgG1) Fc domain.MethodsHuman PBMCs were tested to demonstrate cellular activity and specificity of CUE-102, while in vivo activity of CUE-102 was assessed in HLA-A2 transgenic mice. HLA-A2/WT1-specific TCRs were validated and expressed in primary human CD8 T cells. Tetramer staining and flow cytometry identified cell populations and activation markers.ResultsMultiple in vitro assessments demonstrate that CUE-102 selectively activates and expands WT1-specific CD8+ T cells from PBMC of healthy and cancer bearing donors. These CUE-102-expanded CD8+ T cells exhibit polyfunctional and cytotoxic responses upon challenge with WT1-presenting target cells. In addition, significant functional attenuation of the IL-2 components of CUE-102 was shown, similar to preclinical results obtained with CUE-101. In vivo studies in HLA-A2 transgenic mice confirm that CUE-102 elicits and expands polyfunctional WT1-specific CD8+ T cells from naïve and previously immunized mice without significantly altering the frequencies of other immune lineages. The WT1-specific CD8+ T cells expanded in vivo exhibit polyfunctionality in response to peptide-loaded target cells, and selectively kill WT1-presenting target cells in vivo.ConclusionsCUE-102 elicits selective expansion of a WT1-specific population of cytotoxic CD8+ T cells both in vitro and in vivo. These results, together with its similarity to CUE-101, support its anticipated tolerability profile and potential for clinical efficacy in a Phase 1 trial planned to initiate in 2022.Ethics ApprovalAll animal studies followed guidance from the SmartLabs Institutional Animal Care and Use Committee protocol MIL-100 and were performed in compliance with federal guidelines.

scholarly journals Blockade of Interleukin 27 Signaling Attenuates Graft Versus Host Disease By Augmenting CD4+ and CD8+ Regulatory T Cell Reconstitution

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 150-150
Author(s):  
Ludovic Belle ◽  
Kimberle A. Agle ◽  
Vivian Zhou ◽  
Vanessa Yuan ◽  
Jie Sun ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Graft Versus Host Disease ◽  
Cd8 T Cells ◽  
Regulatory T Cell ◽  
Wild Type ◽  
Host Disease ◽  
Graft Versus Host ◽  
Target Organs ◽  
Ifn Γ

Abstract The interleukin-6 (IL-6) cytokine superfamily (i.e. IL-6, IL-12, and IL-23) plays a major role in the modulation of inflammatory and regulatory pathways during graft versus host disease (GVHD). IL-27, a recently discovered member of this family, is a heterodimeric cytokine that is composed of the p28 and EBI3 subunits and signals through a heterodimeric receptor composed of WSX-1 and gp130. Notably, IL-6 also uses gp130 as a signaling component which biologically links IL-27 and IL-6. IL-27 has been shown to have opposing proinflammatory and immunoregulatory effects, but its role in GVHD is not well understood. To define the functional significance of IL-27, lethally irradiated Balb/c (H-2d) mice were transplanted with C57BL/6J (H-2b) BM and spleen cells, and then treated with an anti-IL-27p28-specific antibody on days 0 and +6. p28 antibody-treated animals had significantly improved weight recovery and overall survival (47% versus 0% survival at day 60, p=0.002), as well as reduced numbers of proinflammatory CD4+ and CD8+ IFN-γ+ T cells in GVHD target organs, when compared to isotype control antibody-treated mice. A similar outcome was observed in an MHC-matched, minor antigen disparate model (B6→Balb.B), indicating that this was not a strain-specific phenomenon. Given the similarities between IL-6 and IL-27, we examined whether blockade of IL-27 promoted regulatory T cell (Treg) reconstitution as has been observed with inhibition of IL-6 signaling. Recipients transplanted with BM grafts from B6 Foxp3EGFP reporter animals and treated with p28 antibody had a significant increase in the number of CD4+ nTregs, CD4+ iTregs and CD8+ iTregs in GVHD target organs, indicating that blockade of IL-27 augmented global Treg reconstitution. In fact, inhibition of IL-27 was more effective at augmenting Treg reconstitution than comparable antibody blockade of IL-6. To further elucidate the role of IL-27, we employed transgenic IL-27−/− and IL-27R−/− animals to dissect the relevant contributions of donor and recipient populations. Paradoxically, we observed that transplantation with IL-27−/− donor grafts exacerbated GVHD mortality and augmented accumulation of proinflammatory T cells, whereas transplantation of recipient IL-27−/− mice with wild type grafts had no effect on transplant outcomes. This discordance between antibody-based and genetic studies was unexpected and led us to consider whether there were steady state alterations in T cells from IL-27−/− animals that biased these cells towards a proinflammatory phenotype. To that end, we observed that naive CD8+ T cells from IL-27−/− mice had greater IFN-γ production than wild type cells after in vitro polyclonal stimulation and CD4+ nTregs from these animals had diminished expression of CXCR3 which is critical for Treg trafficking into inflamed tissue sites. Thus, the lack of endogenous IL-27 resulted in intrinsic immune dysregulation which led to an exacerbation of GVHD after transfer of these T cells into recipients. To resolve this paradox, we employed IL-27R−/− (WSX-1−/−) mice and demonstrated that mice transplanted with IL-27R−/− grafts had enhanced weight recovery and survival providing confirmation that blockade of IL-27 signaling reduced GVHD. In addition, using IL-27R−/− Foxp3EGFP reporter mice, we observed increased frequencies and numbers of CD4+ and CD8+ Foxp3+ T cells in mice reconstituted with IL-27R−/− grafts, confirming results observed with p28 antibody blockade. Since IL-10 is a mechanism by which CD4+ Tregs suppress GVHD and IL-27 has been shown to enhance T cell-derived IL-10 secretion in nontransplant models, we examined whether IL-27 blockade adversely affected IL-10 production by Tregs. Recipients transplanted with marrow grafts from IL-10.BitFoxp3EGFP dual reporter animals and treated with p28 antibody had a significant reduction in the frequency of IL-10-producing conventional CD4+ and CD8+ T cells in GVHD target organs. Notably, however, there was no difference in the frequency of CD4+ Foxp3+ IL-10+ T cells, indicating that blockade of IL-27 signaling preferentially affected conventional T cells and had no adverse effect on CD4+ Foxp3+ T cell-derived IL-10 production. In summary, these studies demonstrate that blockade of IL-27 signaling potently augments Treg reconstitution leading to a reduction in the severity of GVHD and may therefore represent a novel strategy to reduce mortality from this disease in man. Disclosures No relevant conflicts of interest to declare.

scholarly journals MYC Inhibition and TP53 Activation Synergistically Suppress Immune Checkpoint Ligand PD-L1 Expression in AML Cells

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 1667-1667
Author(s):  
Joshua B. Bland ◽  
William T. Tse
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Cells ◽  
Immune Checkpoint ◽  
Dose Effect ◽  
Target Cells ◽  
Activated T Cells ◽  
Activation Markers ◽  
Tnf Α ◽  
Ifn Γ

Abstract Expression of immune checkpoint ligands is a mechanism that many tumors use to escape attack by host immune cells. PD-L1, the ligand for checkpoint receptor PD-1 on T cells, is often expressed on tumor cells. Engagement of PD-1 on T cells by PD-L1 on tumor cells attenuates T-cell receptor signaling and suppresses anti-tumor response. PD-1 and PD-L1 blocking antibodies have been implemented clinically as treatment for many cancers, but the pattern of PD-L1 expression on AML is not well characterized. To answer this question, we studied how PD-L1 expression on AML is regulated under in vitro conditions that simulate the leukemia-host microenvironment. We examined surface expression of PD-L1 by flow cytometry on 4 AML lines, THP-1, KG1, KG1a, HL60, and a CML line, K562. Under basal conditions, these lines expressed no or low levels of PDL1. The AML cells were then subjected to conditions that mimic the leukemia-host microenvironment. AML cells were stained with the green fluorescent dye CFSE and co-cultured with Ficoll-separated PMNCs from healthy donors. After a day of co-culture, expression of PD-L1 was analyzed on AML cells and PD-1, CD25 and CD69 activation markers on PMNCs. Only a small increase of PD-L1, up to 2-4 fold, was seen on AML cells under this condition. To simulate the pro-inflammatory milieu in the tumor microenvironment, anti-CD3/CD28 microbeads were then added in culture to activate T cells. We observed a marked up-regulation of PD-L1 on AML cells, up to 5-60 fold, plus prominent expression of PD-1, CD25 and CD69 on T cells. These findings were confirmed by an alternative method of T cell activation in which AML cells were first coated with an anti-CD123 antibody, linked to anti-CD3/CD28 antibodies via a biotin-streptavidin bridge, and then cultured with PMNCs. To test whether pro-inflammatory cytokines were the sole inducers of PD-L1 expression, AML cells were treated with IFN-γ or TNF-α alone. IFN-γ treatment enhanced PD-L1 expression by 2-10 fold, while TNF-α showed a <2-fold increase. These results show that expression of PD-L1 on AML is dynamically regulated through interaction with activated T cells, by multiple mechanisms including cytokine production and cell-cell interaction. MYC has been shown to regulate PD-L1 expression on T-ALL and solid tumors (Science 2016; 352:227). We asked whether MYC inhibition would suppress PD-L1 on AML. AML and PMNCs were co-cultured in the presence of anti-CD3/CD28 beads, with JQ1, a BET bromodomain inhibitor that blocks MYC expression. JQ1 inhibited PD-L1 expression by >90%. Dose-effect titration showed sigmoidal curves with ED50 of 0.03 to 0.1 μM for the 5 AML lines. Treatment with another MYC inhibitor, CPI-203, yielded similar results. These observations indicate that MYC inhibition can suppress PD-L1 expression on AML induced by activated T cells. TP53 has been shown to regulate PD-L1 expression on non-small cell lung cancer (JNCI 2016; 108:djv303). We asked whether TP53 activation in AML would also affect PD-L1 expression. Since the AML lines we used did not express wild-type TP53, we overexpressed TP53 in these cells by transfecting with a TP53-GFP plasmid. Expression of TP53 in the cells decreased PD-L1 levels by >80%. Treatment of the cells with pifithrin, an inhibitor that blocks trans-activating function of TP53, did not rescue PD-L1 expression, suggesting that the effect of TP53 on PD-L1 expression is independent of its canonical trans-activating pathway. We asked if MYC and TP53 would synergistically affect PD-L1 expression on AML. We transfected AML cells with the TP53-GFP plasmid and co-cultured the cells with PMNCs and anti-CD3-/CD28 beads, in the presence or absence of JQ1. We found that JQ1 treatment of TP53-transfected cells further decreased PD-L1 expression by another 15%, indicating that MYC and TP53 independently and synergistically affect PD-L1 expression on AML. In summary, PD-L1 expression on AML cells is dynamically up-regulated upon interaction with activated T cells and suppressed by perturbation of the MYC and TP53 pathways. These findings have implications in the use of immune effector cell therapy against AML, since the activated effector cells could up-regulate PD-L1 expression on target cells and attenuate anti-leukemia effects. MYC inhibitors and TP53 activators could potentially be used in combination to suppress PD-L1 up-regulation and abrogate the ability of AML cells to escape host immune elimination. Disclosures No relevant conflicts of interest to declare.

High Avidity HLA-A2-Restricted CD8+ T Cells against the Wilms Tumor Protein (WT1) Can Be Isolated Only from HLA-A2 Negative Donors Not Subjected to HLA-A2-Mediated Thymic Deletion

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3895-3895
Author(s):  
Inge Jedema ◽  
Marian van de Meent ◽  
Willem J.J. Falkenburg ◽  
Michel G.D. Kester ◽  
Roel Willemze ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Wilms Tumor ◽  
Target Cells ◽  
Thymic Selection ◽  
High Avidity ◽  
Normal Peripheral Blood ◽  
Donor T Cells ◽  
Low Levels

Abstract The anti-tumor effect of donor lymphocyte infusions (DLI) after HLA-matched allogeneic stem cell transplantation (allo-SCT) can be mediated by donor T cells recognizing minor histocompatibility antigens (mHag) in the context of self HLA on the malignant cells of the recipient. However, T cells recognizing self antigens (Ag) that are overexpressed in malignant cells like the Wilms tumor protein (WT1) have also been proposed to contribute to the anti-tumor reactivity both after allo- and autologous SCT. WT1 is expressed in various types of cancer, including hematological malignancies at higher levels compared to their non-malignant counterparts. Different groups have isolated CD8+ HLA-A2 restricted WT1-specific T cells after HLA-matched transplantation and/or WT1 vaccination. Although these T cells stain with HLA-A2/WT1 peptide tetrameric complexes and are capable of recognizing peptide loaded HLA-A2+ target cells, recognition of primary leukemic cells could hardly be demonstrated. Stauss et al demonstrated recognition of endogenously processed Ag by WT1 specific T cells. However, these CD8 T cells were isolated in a situation where responder and stimulator cells were mismatched for HLA-A2. Based on these data we hypothesized that high avidity HLA-A2 restricted WT1 specific T cells may be deleted during thymic selection in HLA-A2+ donors. As a result, it is likely that only low avidity HLA-A2 restricted WT1 specific CD8+ T cells can be isolated from HLA-A2 positive donors, whereas it might be possible to isolate high avidity HLA-A2 restricted WT1 specific T cells from HLA-A2 negative donors due to the absence of the HLA restriction element in the thymus irrespective of the local WT1 expression. To test this hypothesis, we induced immune responses against the HLA-A2 binding WT1-derived peptide RMFPNAPYL using either HLA-A2+ or A2- donor T cells as responder cells. In case of HLA-A2+ donors (n=3) we stimulated CD45RO depleted donor T cells with autologous monocyte-derived antigen-presenting cells (APCs) loaded with 1E-6M WT1 peptide in the presence of 5ng/mL IL-7. At day 10 we either enriched tetramer-positive cells using immunomagnetic beads (MACS) or restimulated the responses with peptide-loaded autologous PBMC. At day 20 tetramer positive cells were isolated in bulk cultures and single cell/well by flowcytometric cell sorting. When using HLA-A2 negative donor T cells as responder cells, we used HLA-A2+ stimulator cells from an unrelated donor matched for all other class I alleles. The similar protocol was used for the induction of the immune response. At day 10 CD4+ T cells were depleted and the WT1 specific T cells were either enriched using tetramers and MACS or restimulated with peptide loaded HLA-A2+ PBMC. Using these approaches we were capable of isolating CD8+ T cell clones staining brightly with the A2/WT1 tetramer and expressing different T cell receptors (TCRs). HLA-A2+ WT1 specific T cells recognized only HLA-A2+ target cells loaded with 1E-8-1E-6M peptide both in IFNg release assays and cytotoxicity assays. Especially peptide-loaded target cells with an APC phenotype like EBVs were recognized efficiently, whereas normal peripheral blood cells were only recognized when loaded with 1E-6M peptide. In contrast, the HLA-A2 negative WT1-specific T cells efficiently recognized normal peripheral blood cells upon loading of <1E-9M WT1 peptide, indicating that these T cells express TCRs with a higher affinity for the WT1 peptide compared to the HLA-A2+ WT1-specific T cells. Strikingly, EBV-LCL as well as TAP-deficient T2 cells were recognized by the HLA-A2 negative T cells even in the absence of exogenously loaded WT1 peptide. This might be due to the efficient recognition by the high avidity T cells of low levels of WT1 presented in HLA-A2 processed from the endogenous WT1 expression. However, due to the absence of HLA-A2 mediated thymic selection in HLA-A2 negative donors, cross-recognition of other peptides in HLA-A2 may also occur. In conclusion, high avidity WT1 specific CD8+ T cells could be exclusively isolated from HLA-A2 negative donor cells. These high avidity T cells are capable of recognizing target cells expressing very low levels of WT1. These T cell responses will gain more insight into the correlation of WT1 expression in different normal and malignant cell types and the recognition by high avidity WT1 T cells, and the clinical applicability of T cells directed against self antigens.

scholarly journals CD8 T Cells Require Bcl-3 for Maximal Gamma Interferon Production upon Secondary Exposure to Antigen

2006 ◽  
Vol 74 (7) ◽  
pp. 4180-4189 ◽  
Author(s):  
Paula M. Chilton ◽  
Thomas C. Mitchell
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Survival Function ◽  
Ectopic Expression ◽  
Gamma Interferon ◽  
Wild Type ◽  
Activated T Cells ◽  
Ifn Γ

ABSTRACT Adjuvant-induced survival of T cells after antigen activation correlates with increased expression of Bcl-3. Bcl-3 is an NF-κB/IκB family member and has been implicated in transcriptional regulation in several cell types. We tested the ability of mice deficient in Bcl-3 (Bcl-3 KO) to exhibit T-cell adjuvant-induced survival after challenge with the superantigen staphylococcal enterotoxin B (SEB), using lipopolysaccharide (LPS) as a natural adjuvant. These studies showed that Bcl-3 is required for secondary gamma interferon (IFN-γ) production by CD8 T cells but not for adjuvant-induced survival effects. Specifically, wild-type and Bcl-3 KO mice exhibited comparable long-term increases in the Vβ8+ T-cell populations, indicating no lack of survival in response to adjuvant stimulation in the Bcl-3 KO activated T cells. Ectopic expression of the Bcl-3-related molecules IκBα, IκBβ, and IκBε in SEB-activated T cells increased survival during in vitro culture in the absence of adjuvant, suggesting that these IκB molecules could exert a survival function in antigen-activated T cells in place of Bcl-3. However, Vβ8+ CD8 T cells from SEB- plus LPS-treated Bcl-3 KO mice produced less IFN-γ upon in vitro restimulation than Vβ8+ CD8 T cells from wild-type mice. Therefore, Bcl-3 plays a unique role in the regulation of IFN-γ production in this model system.

scholarly journals Virally Activated CD8 T Cells Home to Mycobacterium bovis BCG-Induced Granulomas but Enhance Antimycobacterial Protection Only in Immunodeficient Mice

2006 ◽  
Vol 75 (3) ◽  
pp. 1154-1166 ◽  
Author(s):  
Laura H. Hogan ◽  
Dominic O. Co ◽  
Jozsef Karman ◽  
Erika Heninger ◽  
M. Suresh ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mycobacterium Bovis ◽  
Cd8 T Cells ◽  
Bacterial Load ◽  
Granulomatous Inflammation ◽  
Cd8 T Cell ◽  
Activated T Cells ◽  
Immunodeficient Mice ◽  
Ifn Γ

ABSTRACT The effect of secondary infections on CD4 T-cell-regulated chronic granulomatous inflammation is not well understood. Here, we have investigated the effect of an acute viral infection on the cellular composition and bacterial protection in Mycobacterium bovis strain bacille Calmette-Guérin (BCG)-induced granulomas using an immunocompetent and a partially immunodeficient murine model. Acute lymphocytic choriomeningitis virus (LCMV) coinfection of C57BL/6 mice led to substantial accumulation of gamma interferon (IFN-γ)-producing LCMV-specific T cells in liver granulomas and increased local IFN-γ. Despite traffic of activated T cells that resulted in a CD8 T-cell-dominated granuloma, the BCG liver organ load was unaltered from control levels. In OT-1 T-cell-receptor (TCR) transgenic mice, ovalbumin (OVA) immunization or LCMV coinfection of BCG-infected mice induced CD8 T-cell-dominated granulomas containing large numbers of non-BCG-specific activated T cells. The higher baseline BCG organ load in this CD8 TCR transgenic animal allowed us to demonstrate that OVA immunization and LCMV coinfection increased anti-BCG protection. The bacterial load remained substantially higher than in mice with a more complete TCR repertoire. Overall, the present study suggests that peripherally activated CD8 T cells can be recruited to chronic inflammatory sites, but their contribution to protective immunity is limited to conditions of underlying immunodeficiency.

148 Identification of prostate-restricted epithelial antigens for transgenic T cell adoptive therapy against prostate cancer

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A161-A161
Author(s):  
Diana DeLucia ◽  
Tiffany Pariva ◽  
Roland Strong ◽  
Owen Witte ◽  
John Lee
Keyword(s):  
Prostate Cancer ◽  
T Cells ◽  
T Cell ◽  
Single Cell ◽  
Cd8 T Cells ◽  
Adoptive Therapy ◽  
Mhc I ◽  
Epithelial Antigens ◽  
Ifn Γ ◽  
Stimulation Of

BackgroundIn advanced prostate cancer (PCa), progression to castration-resistant PCa (CRPC) is inevitable and novel therapies for CRPC are needed. Adoptive transfer of T cells targeting tumor antigens is a promising approach in the cancer field. Unfortunately, identifying antigens expressed exclusively in prostate tumor cells has been challenging. Since the prostate is not an essential organ, we alternatively selected prostate-restricted epithelial antigens (PREAs) expressed in both malignant and normal prostate tissue for transgenic T cell studies.MethodsRNA-seq data sets identifying genes enriched in PCa were cross-referenced with the NIH Genotype-Expression database to identify PREAs. Using a novel molecular immunology approach, select PREAs and major histocompatibility complex class I (MHC-I) molecules were co-expressed in HEK293F cells, from which MHC–peptide complexes were efficiently isolated. Peptides were eluted and sequenced by mass spectrometry. Peptide–MHC binding was validated with a T2 stabilization assay and peptide immunodominance was determined using an interferon-γ (IFN-γ) ELISpot assay following stimulation of healthy HLA-A2+ peripheral blood mononuclear cells (PBMC) with peptide pools. Following peptide stimulation, CD8+ T cells with peptide-specific T cell receptors (TCR) were enriched by peptide–MHC-I dextramer labeling and fluorescence activated cell sorting for single cell TCR α/β chain sequencing.ResultsWe identified 11 A2+ peptides (8 previously unpublished) from prostatic acid phosphatase (ACPP), solute carrier family 45 member 3 (SLC45A3), and NK3 homeobox 1 (NKX3.1) that bound to HLA-A2 with varying affinities. Extended culture stimulation of PBMC with peptide pools from each PREA, compared to the standard overnight culture, revealed a greater number of IFN-γ producing cells overall and a greater breadth of response across all the peptides. Antigen specific CD8+ T cells were detectable at low frequencies in both male and female healthy PBMC for 7 of the 11 peptides. Dextramer-sorted antigen-specific cells were used for single-cell paired TCR αβ sequencing and transgenic T cell development.ConclusionsThrough this work we identified HLA-A2-presented antigenic peptides from the PREAs ACPP, SLC45A3, and NKX3.1 that can induce the expansion of IFN-γ producing CD8+ T cells. Through peptide–MHC-I dextramer labeling, we isolated PREA-specific CD8+ T cells and characterized TCR αβ sequences with potential anti-tumor functionality. Our results highlight a rapid and directed platform for the development of MHC-I-restricted transgenic CD8+ T cells targeting lineage-specific proteins expressed in prostate epithelia for adoptive therapy of advanced PCa.

scholarly journals Gamma Interferon Production, but Not Perforin-Mediated Cytolytic Activity, of T Cells Is Required for Prevention of Toxoplasmic Encephalitis in BALB/c Mice Genetically Resistant to the Disease

2004 ◽  
Vol 72 (8) ◽  
pp. 4432-4438 ◽  
Author(s):  
Xisheng Wang ◽  
Hoil Kang ◽  
Takane Kikuchi ◽  
Yasuhiro Suzuki
Keyword(s):  
T Cells ◽  
T Cell ◽  
Nude Mice ◽  
Genetic Resistance ◽  
Cytolytic Activity ◽  
Gamma Interferon ◽  
Toxoplasmic Encephalitis ◽  
Wild Type ◽  
Ifn Γ

ABSTRACT We previously showed the requirement of both T cells and gamma interferon (IFN-γ)-producing non-T cells for the genetic resistance of BALB/c mice to the development of toxoplasmic encephalitis (TE). In order to define the role of IFN-γ production and the perforin-mediated cytotoxicity of T cells in this resistance, we obtained immune T cells from spleens of infected IFN-γ knockout (IFN-γ−/−), perforin knockout (PO), and wild-type BALB/c mice and transferred them into infected and sulfadiazine-treated athymic nude mice, which lack T cells but have IFN-γ-producing non-T cells. Control nude mice that had not received any T cells developed severe TE and died after discontinuation of sulfadiazine treatment due to the reactivation of infection. Animals that had received immune T cells from either wild-type or PO mice did not develop TE and survived. In contrast, nude mice that had received immune T cells from IFN-γ−/− mice developed severe TE and died as early as control nude mice. T cells obtained from the spleens of animals that had received either PO or wild-type T cells produced large amounts of IFN-γ after stimulation with Toxoplasma gondii antigens in vitro. In addition, the amounts of IFN-γ mRNA expressed in the brains of PO T-cell recipients did not differ from those in wild-type T-cell recipients. Furthermore, PO mice did not develop TE after infection, and their IFN-γ production was equivalent to or higher than that of wild-type animals. These results indicate that IFN-γ production, but not perforin-mediated cytotoxic activity, by T cells is required for the prevention of TE in genetically resistant BALB/c mice.

scholarly journals 677 Reverse abscopal effect: intertumoral heterogeneity suppresses systemic CD8 T cell-mediated antitumor immunity and confers PD-1 inhibitor resistance in synchronous melanoma

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A705-A705
Author(s):  
Shuyang Qin ◽  
Booyeon Han ◽  
Alexander Chacon ◽  
Alexa Melucci ◽  
Alyssa Williams ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Line ◽  
Cd8 T Cells ◽  
Antitumor Immunity ◽  
Immune Escape ◽  
Cd8 T Cell ◽  
Abscopal Effect ◽  
Immunogenic Tumor ◽  
Ifn Γ

BackgroundDespite recent advancements in systemic therapy, only a minority of metastatic patients develop meaningful clinical responses to immune checkpoint inhibitors. Inherent genetic instability of melanoma generates genomically and microenvironmentally distinct metastases. These different tumor microenvironments (TMEs) contain numerous T cell suppression mechanisms, such as upregulation of the PD-1/PD-L1 exhaustion pathway. However, as synchronous metastases share one host immune system, intertumoral heterogeneity may result in increasing cross-talk between metastases that impairs systemic antitumor immunity and promotes PD-1 immunotherapy resistance.MethodsYUMM 1.7 (less immunogenic) and YUMMER 1.7 (more immunogenic cell line derived from YUMM following UVB irradiation) melanoma cell lines were simultaneously injected into opposite flanks of the same mice as a model of synchronous melanoma. We assessed tumor growth in wildtype, interferon-gamma (IFN-γ) knockout, and CD8-depleted mice as well as in response to PD-1 inhibitor. We characterized the TME with flow cytometry and performed TCR sequencing on tumor-infiltrating CD8 T cells.ResultsDistinct TMEs were observed for YUMM and YUMMER tumors simultaneously grown in the same mouse. The presence of the less immunogenic YUMM tumor allows the more immunogenic YUMMER tumors to escape IFN-γ and CD8 T cell-mediated rejection, despite abundant tumor-infiltrating, clonally expanded CD8 T cells. Identical immunodominant CD8 T cell clones were found in both YUMM and YUMMER tumors within the same mouse. Synchronous YUMMER-infiltrating CD8 T cells exhibit suppressed phenotypes, including increased persistence of surface PD-1 and decreased surface CD107a expressions. Simultaneously, these synchronous YUMMER tumors additionally upregulate macrophage surface PD-L1 expression, which potentially contributes to tumor immune escape. Lastly, synchronous YUMMER tumors become resistant to PD-1 inhibition, in direct contrast to control YUMMER tumors.ConclusionsIn a host with multiple melanoma lesions, immunogenicity of all tumors contribute to the systemic antitumor immune response. We show that two synchronous tumors with synonymous mutations (<40%), as is the case with metastatic patients, lead to skewed CD8 T cell expansion of the same clones in both tumors. The presence of a less immunogenic tumor prevents CD8 and IFN-γ mediated rejection of the more immunogenic tumor. Furthermore, CD8 T cells in the more immunogenic tumor exhibit decreased effector function and increased resistance to PD-1 blockade, as tumor-infiltrating macrophages concurrently become more immunosuppressive. These results are highly suggestive of a “reverse abscopal effect,” by which immunologically “cold” tumors generate systemic immunosuppression that facilitate PD-1 immunotherapy resistance and immune escape of all other tumors in synchronous metastatic melanoma patients.AcknowledgementsWe would like to thank Dr. Marcus Bosenberg from the Department of Dermatology at Yale University for kindly gifting us with the YUMMER 1.7 murine melanoma cell line.Ethics ApprovalAnimal experiments were approved by the University Committee on Animal Resources and performed in accordance with University of Rochester approved guidelines.

Sign in / Sign up

Export Citation Format

Share Document