T Cells from Chronic Lymphocytic Leukemia (CLL) Patients Display Dysregulated Expression of Immune Checkpoint Molecules and Activation Markers Mainly Restricted to CD4+ Cells and Correlated with Disease Activity

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4132-4132
Author(s):  
Marzia Palma ◽  
Giusy Gentilcore ◽  
Fariba Mozaffari ◽  
Kia Heimersson ◽  
Barbro Näsman-Glaser ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Immune Checkpoint ◽  
Cd4 T Cells ◽  
Research Funding ◽  
Immune Checkpoints ◽  
Activated T Cells ◽  
Activation Markers ◽  
Cd8 Cells

Abstract Background CLL patients (pts) have impaired humoral and cellular immune functions, which is largely due to profound defects of T-cells. Regulation and activation of T lymphocytes depend not only on T cell receptor signaling but also on co-signaling receptors delivering either inhibitory or stimulatory signals, known as immune checkpoints. CTLA-4 (cytotoxic T lymphocyte-associated antigen-4) is transiently expressed on activated T cells, binding the same ligands as CD28, inhibiting T-cell activation. Similarly, programmed cell death protein 1 (PD-1) is expressed on activated CD4+ and CD8+ T cells inhibiting T-cell functions upon binding to the ligands B7-H1 (PD-L1, CD274) and B7-DC (PD-L2, CD273). CD137 is an inducible costimulatory receptor expressed by activated T cells. Dysregulated expression of immune checkpoint receptors on T cells of CLL pts may have an impact on T-cell responsiveness and might be a mechanism for the immune deficiency in the disease. Aim To evaluate the expression of the immune checkpoint molecules CTLA-4, PD-1 and CD137 as well as of the cell proliferation marker Ki67, the activation marker CD69 and of CD103, a marker expressed on regulatory T cells, in T cells from CLL pts in different disease phases. Methods Peripheral blood samples were obtained from 69 CLL pts and 13 healthy control donors (HD). Pts were sub-grouped according to disease phase: indolent vs progressive (i.e. fulfilling criteria for active disease). The expression of CTLA-4, PD-1, PD-L1, CD69, CD103, CD137 and Ki-67 was assessed by flow-cytometry on CD4+ and CD8+ T cells. We also analysed the change in expression of these markers on T cells after 72 hours of PHA stimulation. Results CLL pts (n=17) had a significanty higher percentage of proliferating (Ki67+) CD3+ cells compared to HD (n=7) (median 3.7% in progressive vs 1.7% in indolent CLL vs 0.9% in HD, p=0.004 and p=0.04, respectively) (Fig.1). Progressive CLL pts had a significantly higher percentage Ki67+ CD4+ compared to indolent pts as well as HD (p=0.007 and p=0.001, respectively). Both indolent and progressive pts had higher percentage of Ki67+ CD8+ T cells compared to HD (p=0.01 and p=0.03, respectively). The percentage of CTLA-4+ CD4+ and CTLA-4+ CD8+ cells was low in CLL pts as well as in HD. However, the percentage of PD-1+ CD4+ T cells was significantly higher in progressive (n=32) as compared to indolent (n=35) CLL pts (median 40.3% vs 23.3%, p<0.0001) and HD (n=13) (median 21.5%, p<0.0001) (Fig.2) and correlated positively to the white blood cell counts (WBC) at the time of testing (r=0.29, p=0.03), while no difference was found with regard to the percentage of PD-1+ CD8+ T cells. No difference was observed between CLL pts and HD regarding the expression of PD-L1 on T cells. Both the percentage of CD69+ CD4+ and CD137+ CD4+ T cells were significantly higher in progressive as compared to indolent disease and correlated positively to WBC while no difference was found seen in CD8+ T cells. The percentage of CD103+ T cells was significantly lower in progressive compared to and HD within both the CD4+ (p=0.02) and the CD8+ subpopulations (p=0.02). After 72-hrs of PHA stimulation, PD-1 and CTLA-4 expression increased in CD4+ and CD8+ cells to a similar extent in CLL pts and HD, while PD-L1 increased in HD but not in progressive CLL pts (p=0.03 and p=0.007 for CD4+ and CD8+ cells, respectively). CD69 expression increased to a similar extent in CLL pts and HD, while CD137 expression increased more in T cells from progressive pts compared to HD (p=0.03 and 0.01 for the CD4+ and CD8+ cells, respectively). No increase in CD103 on CD8+ T-cells was observed in CLL pts compared to HD (p=0.04 and p=0.01 for the indolent and progressive pts, respectively). Conclusions Progressive CLL pts have more proliferating (Ki67+) T cells in both the CD4+ and CD8+ compartments compared to HD. CD4+ T-cells in progressive CLL pts display an activated phenotype (CD69+) and express the immune co-stimulatory molecule CD137 at a significantly higher level compared to indolent pts and HD. Nevertheless, the expression of the inhibitory immune checkpoint molecule PD-1 is so high that it is reasonable to assume that these cells are heavily impaired in their immune functions. The differences observed in the expression of immune checkpoints and activation markers between CLL pts in different phases of the disease suggest that major changes occur in the CD4+ T-cell compartment during disease progression. Figure 1. Figure 1. Figure 2. Figure 2. Disclosures Hansson: Jansse Cilag: Research Funding. Österborg:Janssen, Pharmacyclics, Gilead: Consultancy, Research Funding; Novartis: Research Funding.

scholarly journals 643 Vasoactive intestinal peptide as a novel immune checkpoint molecule in activated T cells

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A672-A672
Author(s):  
Sruthi Ravindranathan ◽  
Tenzin Passang Fnu ◽  
Edmund Waller
Keyword(s):  
T Cells ◽  
T Cell ◽  
Vasoactive Intestinal Peptide ◽  
T Cell Activation ◽  
Cd8 T Cells ◽  
Immune Checkpoint ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Checkpoint Inhibitors ◽  
Activated T Cells

BackgroundOnly a fraction of cancer patients responds to current antibody-based immune checkpoint inhibitors.1 Our lab has identified vasoactive intestinal peptide-receptor (VIP-R) signaling as a targetable immune checkpoint pathway in cancer. VIP is a small neuropeptide with known immunosuppressive effects on T cells, in particular, CD4+ T cells.2–5 However, little is known about VIP-R signaling in CD8+ T cells. To define mechanisms by which VIP limits T cell activation and function, we studied the regulation of VIP and VIP receptors (VIP-R) in T cells following their activation in vitro and in mouse models of cancer.MethodsT cells from healthy human donors and murine splenocytes were activated using anti-CD3 coated plates. Western blots measured intracellular pre-pro-VIP, along with its cognate receptors; VPAC1 and VPAC2. Purified cultures of CD4+ and CD8+ T cells were used to interrogate the protein expression on specific T cell subsets. Activation and chemokine receptor expression was assessed by flow cytometry to evaluate T cell response to VIP-R antagonists in vitro and in tumor-bearing mice engrafted with pancreatic cancer cell lines.ResultsBoth murine and human T cells upregulate pre-pro-VIP following TCR stimulation with similar kinetics of VIP receptors between species. VIP expression is upregulated in vivo following treatment of tumor-bearing mice with anti-PD1 MoAb. VIP expression is temporally correlated with the upregulation of other co-inhibitory molecules. VPAC1 expression modestly increased in activated T cells while VPAC2 expression decreased. A non-canonical high molecular weight (HMW) form of VPAC2-related protein robustly and transiently increase in activated T cells. Expression of HMW form of VPAC2 is only detected in activated CD4+ T cells. Of note, activated CD4+ but not CD8+ T cells upregulate pre-pro-VIP. Pharmacological inhibition of VIP-R signaling significantly increased CD69+, OX40+, Lag3+, and PD1+ expression in CD4+ subsets compared to activated T cells without VIP-R antagonists (p < 0.05). In contrast, CD8+ T cells upregulate VPAC1 but not VPAC2 receptor following activation. VIP-R antagonist treatment of activated CD8+ T cells significantly decreased CXCR4+ expression (p < 0.05). CXCR3 and CXCR5 expression were not affected by VIP-R antagonist treatment.ConclusionsVIP-R signaling is a novel immune autocrine and paracrine checkpoint pathway in activated CD4+ T cells. Activated CD4+ and CD8+ T cells demonstrate different kinetics of VPAC1 and VPAC2 expression, suggesting different immune-regulatory responses to VIP-R antagonists. Understanding VIP-R signaling induced during T cell activation can lead to specific drugs that target VIP-R pathways to enhance cancer immunotherapy.AcknowledgementsWe thank healthy volunteers for blood samples. The authors also thank the shared resources at Emory University, namely, Emory Flow Cytometry Core (EFCC) and Integrated Cellular Imaging Core (ICI) and Yerkes Nonhuman Primate Genomics Core that provided services or instruments at subsidized cost to conduct some of the reported experiments. This work was supported in part by Katz Foundation funding, Georgia Research Alliance, and Emory School of Medicine Dean's Imagine, Innovate and Impact (I3) venture award to Edmund K. Waller.ReferencesDarvin P, Toor SM, Sasidharan Nair V, Elkord E. Immune checkpoint inhibitors: recent progress and potential biomarkers. Experimental and Molecular Medicine 2018.Wang HY, Jiang XM, Ganea D. The Neuropeptides VIP and PACAP Inhibit IL-2 Transcription by Decreasing c-Jun and Increasing JunB Expression in T Cells. J Neuroimmunol 2000;104(1):68–78.Delgado M. Vasoactive intestinal peptide generates CD4+CD25+ regulatory T Cells in Vivo. J Leukoc Biol 2005.Anderson P, Gonzalez-Rey E. Vasoactive intestinal peptide induces cell cycle arrest and regulatory functions in human T cells at multiple levels. Mol Cell Biol 2010.Delgado M, Ganea D. Vasoactive intestinal peptide: a neuropeptide with pleiotropic immune functions. Amino Acids. NIH Public Access July 2013, 25–39.Ethics ApprovalDe-identified blood samples from consented healthy volunteers (IRB 00046063) were obtained with approval from Institutional Review Boards.

scholarly journals In CLL, Myeloid-Derived Suppressor Cells and Their Monocytic and Granulocytic Varieties Differ in T-Cell Subset Association and Polarization Induction

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4350-4350
Author(s):  
Gerardo Ferrer ◽  
Brendan Franca ◽  
Pui Yan Chiu ◽  
Stefano Vergani ◽  
Andrea Nicola Mazzarello ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Th17 Cells ◽  
Research Funding ◽  
Suppressor Cells ◽  
Myeloid Derived Suppressor Cells ◽  
Cd8 Cells

Abstract In chronic lymphocytic leukemia (CLL) monoclonal B cells expand and progressively accumulate in the bone marrow, eventually migrating to secondary lymphoid organs for even greater proliferation. At both sites, CLL cells engage in complex, incompletely defined cellular and molecular interactions involving multiple cell types such as T cells, myeloid cells, mesenchymal stromal cells, and matrix, collectively referred to as the "tumor microenvironment". This microenvironment is critical for the survival and proliferation of CLL cells, and data indicate that T cells and myeloid cells have an important role in these processes. In this study, we focus on two cells types: CD4+ T lymphocytes and myeloid-derived suppressor cells (MDSCs). In CLL patients, these populations are altered and impact on clinical outcome. CD4+ T cells comprise several subtypes, and CLL patients often have expanded Th2 and Tregs populations, consistent with the immunosuppressive status of these patients. Moreover, patients with higher numbers of another CD4+ subset, Th17 cells that produce IL-17 and other pro-inflammatory cytokines, can have longer survival times. Although studied minimally in CLL, MDSCs are known suppressors of T cell proliferation in vitro, and expand along with malignant cells in several cancers. However, no information is available about their effects on CD4+ T cell differentiation or on B-cell biology in CLL. In a cohort of 56 untreated CLL patients, we first explored correlation of the numbers of MDSCs and autologous T cells, using flow cytometry. CD3+ cell numbers significantly paralleled total MDSCs and monocyte-like MDSCs (mMDSCs) (P = 0.002, Spearman r = 0.44; P = 0.004, Spearman r = 0.41, respectively). Interestingly, MDSCs correlated with CD4+ and CD8+ T-cells (P < 0.001, Spearman r = 0.646; P < 0.001, Spearman r = 0.61, respectively). However, the correlation of MDSC subpopulations with CD4+ and CD8+ cells differed: mMDSCs associated significantly with CD4+ cells (P < 0.001, Spearman r = 0.73) and granulocyte-like MDSCs (gMDSCs) with CD8+ cells (P= 0.008; Spearman r = 0.45). Furthermore, although gMDSCs did not correlate with the numbers of CD4+ T-cells, we observed that they positively paralleled Tregs defined as CD3+/CD4+/CD25+/CD127-/FoxP3+ cells (P = 0.020, Spearman r = 0.44). Other subpopulations are currently under study. To address the effect of MDSCs on CD4+ cell differentiation, we FACS sorted CD3+/CD45RO- naïve CD4+ lymphocytes and stimulated them in vitro with anti-CD3/CD28 beads and IL2 in the presence or absence of mMDSCs (HLA-DRlo/CD11b+/CD33+/CD14+), gMDSCs (HLA-DRlo/CD11b+/CD33+/CD15+) or monocytes (HLA-DRhi/CD11b+/CD14+); these studies involved samples from 3 CLLs and 3 healthy controls (HCs). On day 7, cells were harvested and cytokine production was quantified by intracellular flow cytometry as the percentages of the following populations: Th1 (INFγ), Th2 (IL-4), Tregs (FoxP3), Th17 (IL-17A and IL-17F), Th9 (IL-9) and Th22 (IL-22). Culturing CLL or HC T cells in the absence of MDSCs revealed a lower percentage of cytokine-producing cells (24% vs. 55%; P = 0.017) in CLL, which was mainly due to a reduction in IL-4+ cells (P = 0.066). However, when analyzing the effects of MDSC subsets on the polarization of CLL or HC T cell, gMDSCs promoted significantly more FoxP3+ and less IL-22+ cells in CLL than in HC (P = 0.025 and P = 0.048, respectively). When analyzing only CLL T cells, supplementation with mMDSCs induced a reduction in IL-22+ cells (P = 0.027) and an insignificant increase of IL-4+ and IL-17+ cells. Conversely monocytes supported an expansion of INFγ+ T-cells (P=0.066), and gMDSCS promoted an increase of IL-9+ cells (P = 0.046) and a reduction of FoxP3+ cells (P = 0.019). In summary, in CLL the absolute numbers of total MDSCs and T cells are tightly linked. There is a significant correlation between CD4+ T cells and mMDSCs, and between CD8+ T cells and gMDSCs. Additionally, in CLL naïve CD4+ differentiation appears reduced compared to HC, in concordance with lower T-cell responses previously reported. Moreover, the preliminary aspects of the study suggest that CLL mMDSCs promote an expansion of Th2, Th17 cells and a reduction of Th22 cells, and monocytes enhance Th1s. Unexpectedly, since we observed a significant positive correlation in the PBMCs, gMDSCs may reduce Tregs and augment Th9. These findings depict differential consequences of CLL T cell - MDSC / mMDSC / gMDSC interactions. Disclosures Stamatopoulos: Abbvie: Honoraria, Other: Travel expenses; Gilead: Consultancy, Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Janssen: Honoraria, Other: Travel expenses, Research Funding.

scholarly journals 754 TIGIT-PVR is a key immune checkpoint and therapeutic target in HPV-positive head and neck squamous cell carcinomas

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A788-A788
Author(s):  
Xiuning Le ◽  
Minghao Dang ◽  
Venkatesh Hegde ◽  
Bo Jiang ◽  
Ravaen Slay ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Murine Model ◽  
Immune Checkpoint ◽  
Therapeutic Target ◽  
Therapeutic Efficacy ◽  
Cd8 T Cell ◽  
Immune Checkpoints ◽  
Rna Seq

BackgroundHuman papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HPV+ HNSCC) is a disease that has moderate response to anti-PD-1/L1 immune checkpoint blockade, with the response rates less than 20% and median progression-free survival less than 3 months. A greater understanding of tumor intrinsic and extrinsic factors that restrict anti-tumor immunity in the tumor immune microenvironment (TIME) is needed to identify other immune checkpoints to enhance therapeutic efficacy.MethodsTwo cohorts (TCGA n=72 and a separate cohort n=84) of surgically resected, treatment-naïve HPV+ HNSCC with RNA-seq were analyzed to understand the immune features. In addition, single-cell RNA-seq and TCR-seq were performed on 18 cases to further delineate the immune molecules' interactions. An immune-competent murine HPV+ HNSCC model was used to preliminarily evaluate the therapeutic efficacy.ResultsIn two bulk-sequenced HPV+ HNSCC cohorts, TIGIT ligands PVR and NECTIN2 were found to associate with an epithelial-to-mesenchymal gene expression signature, suppression of IFNα and IFNγ signaling, a stromal-enriched or immune-excluded TIME, and poor survival. Single-cell RNA-seq of over 72,000 cells of HPV+ HNSCC revealed that the PVR/NECTIN ligand TIGIT was highly prevalent in T-cells (34%), significantly higher than PD1- (20%, p<0.01). There is an enrichment of cell-cell interactions mediated by TIGIT-PVR/NECTIN2 in the TIME of HPV+HNSCC versus normal tonsil. TIGIT was the most differentially upregulated immune checkpoint on clonally expanded CD8+T-cells and was abundant on antigen-experienced, tissue-resident memory CD8+T-cell and T-regulatory subsets. TIGIT ligands PVR, NECTIN1, and NECTIN2 were abundant on mature regulatory dendritic cells (DCs), immunosuppressive plasmacytoid (p)DCs, and macrophages, respectively. TIGIT and PD-1 co-blockade in the mEER syngeneic murine model significantly reduced tumor growth, improved survival, restored effector function of HPV16E7-specific CD8+T cells, natural killer cells, and DCs, and conferred tumor re-challenge protection.ConclusionsTIGIT-PVR/NECTIN receptors/ligands are more abundant than PD-1/L1 in the TIME of HPV+ HNSCC. Co-blockade of TIGIT and PD-1 immune checkpoints enhanced anti-tumor efficacy in a CD8+ T-cell-dependent manner and conferred long-term immune protection in a murine model. Our study nominates TIGIT as a therapeutic target for HPV+ HNSCC.

The ICOS:ICOSL Costimulatory Pathway Plays an Important Role in GVHD and Bone Marrow (BM) Graft Rejection.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 591-591 ◽  
Author(s):  
Patricia Taylor ◽  
Angela Panoskaltsis-Mortari ◽  
Gordon Freeman ◽  
Arlene Sharpe ◽  
Randolph Noelle ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Family Member ◽  
Cd8 T Cells ◽  
Graft Rejection ◽  
Cd4 T Cells ◽  
Fluorescent Protein ◽  
Wild Type ◽  
Activated T Cells ◽  
Effector Cells

Abstract ICOS, a CD28/CTLA-4 family member, is expressed on activated T cells. ICOS Ligand, a B7 family member, is constitutively expressed on B cells, monocytes and some T cells. Through the use of blocking anti-ICOS mAb and ICOS deficient (−/−) mice, we found that ICOS:ICOSL interactions play an important role in GVHD and BM graft rejection. Anti-ICOS mAb (given d-1 to d28 post BMT) significantly delayed or reduced mortality at 2 different T cell doses in a full MHC-disparate GVHD model. ICOS−/− T cells led to delayed or reduced mortality at 3 different cell doses compared to wild-type T cells. ICOS−/− CD4+ or CD8+ T cells infused into class II- or class I-disparate recipients, respectively, revealed that ICOS:ICOSL interactions regulate both CD4+ and CD8+ T cell alloresponses. Anti-ICOS inhibited GVHD in a CD28-independent fashion. Anti-ICOS inhibited GVHD mediated by either stat 4−/− or stat 6−/− T cells indicating that the ICOS pathway regulates both Th2 and Th1-mediated GVHD. In contrast to blockade of the B7:CD28/CTLA-4, CD40L:CD40 or the OX40:OX40L pathway, anti-ICOS mAb inhibited GVHD even when delayed until d5 post BMT, a time when substantial T cell expansion has occurred. A TCR transgenic model of GVHD was used to further study effects of ICOS:ICOSL blockade. All CB6 F1 recipients of anti-host alloreactive 2C CD8+ and TEa CD4+ T cells succumbed to GVHD mortality by d18 after transfer of cells. In contrast, 88% of anti-ICOS-treated mice survived long-term. Evaluation of spleens early after transplant revealed that anti-ICOS mAb reduced the number of TEa CD4+ cells by 44% and 2C CD8+ cells by 83%. Green fluorescent protein (GFP) 2C CD8+ and GFP TEa CD4+ T cells were infused into irradiated CB6 F1 mice and irrelevant or anti-ICOS mAb was administered. Mice were imaged on d4, 7 and 12 after T cell transfer. By d7, pronounced infiltration of GFP+ cells was noted in the peripheral and mesenteric LN, spleen, Peyer’s patches (PP), skin, gingiva, liver, kidney, lung, ileum, and colon of GVHD control mice. In contrast, there were fewer GFP+ cells in the spleen, ileum, colon, kidney, lung, skin and gingiva of anti-ICOS-treated mice, although there was no decrease in GFP+ cells in LNs or PP. To study the role of host ICOS expression in BM graft rejection, wild-type or ICOS−/− mice were sublethally irradiated and given allogeneic BM and evaluated for donor chimerism at 6 weeks post BMT. Five of 10 wild type mice engrafted (ave − 26% donor) in contrast to all 10 of ICOS−/− mice (ave − 71% donor). Collectively, these data indicate that ICOS:ICOSL interactions play an important role in GVHD, whether mediated by CD4+ Th1 or Th2 T cells or CD8+ T cells. Importantly, blockade of ICOS:ICOSL after initiation of alloresponses inhibited GVHD, in contrast to blockade of other costimulatory pathways, suggesting that the ICOS pathway may be a novel therapeutic target in primed transplantation situations. Anti-ICOS interfered with expansion of donor T cells in the spleen early after transplant and reduced the number of effector cells in several GVHD target tissues. These data suggest this pathway may be indicated for therapeutic targeting for the inhibition of GVHD and BM graft rejection.

scholarly journals CD4+ T Cell Fate in Multiple Myeloma

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4494-4494
Author(s):  
Rachel Elizabeth Cooke ◽  
Jessica Chung ◽  
Sarah Gabriel ◽  
Hang Quach ◽  
Simon J. Harrison ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Board Of Directors ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Research Funding ◽  
Flow Cytometric Analysis ◽  
Advisory Committees ◽  
Mitochondrial Mass ◽  
Flow Cytometric

Abstract The average incidence of multiple myeloma (MM) is in the 7th decade that coincides with the development of immunosenescence and thymic atrophy, meaning that lymphocyte recovery after lymphopenia-inducing therapies (most notably autologous stem cell transplant, ASCT) is largely reliant on homeostatic proliferation of peripheral T cells rather than replenishing the T cell pool with new thymic emigrants. We have previously shown that there is a significant reduction in circulating naïve T cells with a reciprocal expansion of antigen-experienced cells from newly diagnosed MM (NDMM) to relapsed/refractory disease (RRMM). This results in a reduced TCR repertoire and the accumulation of senescence-associated secretory phenotype cytotoxic T cells, which maintain the ability to produce IFNγ but lose proliferative potential. A reduction in CD4:8 ratio is also a characteristic finding in MM with disease progression, which can be explained by high IL-15 levels in lymphopenic states that preferentially drive expansion of CD8+ memory T cells. We wanted to further evaluate what changes were occurring in the CD4+ T cell population with disease progression in MM. We analyzed paired peripheral blood (PB) samples from patients with NDMM and RRMM, and compared with age-matched normal donors (ND). In the NDMM cohort, we examined T cells from PB samples at baseline, after 4 cycles of lenalidomide and dexamethasone (len/dex), and after ASCT; and in the RRMM cohort samples from baseline and after 6 cycles of len/dex. We firstly confirmed in flow cytometric analysis of T cells at serial intervals in NDMM patients that the reduction in circulating naïve T cells and in CD4:8 ratio occurs post ASCT and does not recover by time of last follow-up. We next utilised RNA-seq to analyse differences in CD4+ T cells from NDMM, RRMM and ND. CD4+ T cells from RRMM showed downregulation of cytosolic ribosomal activity but maintenance of mitochondrial ribosomal activity and significant upregulation of pathways involved with calcium signalling. To this end, we evaluated mitochondrial biogenesis and metabolic pathways involved with mitochondrial respiration. Flow cytometric analysis of mitochondrial mass showed a marked increase in RRMM compared with ND, in keeping with a shift towards memory phenotype. Key rate-limiting enzymes in fatty acid β-oxidation (CPT1-A, ACAA2 and ACADVL) were all significantly increased in RRMM compared with ND. To analyse whether these cells were metabolically active, we also measured mitochondrial membrane potential and reactive oxygen species (ROS), gating on cells with high mitochondrial mass. Mitochondrial membrane potential was significantly increased in RRMM compared with ND, although ROS was reduced. The significance of this is not clear, as ROS are not only implicated in cell senescence and activation-induced cell death, but are also positively involved in tyrosine kinase and PI3K-signalling pathways. PD-1 has been shown to play a role in transitioning activated CD4+ T cells from glycolysis to FAO metabolism, and elevating ROS in activated CD8+ T cells. We analysed PD-1 expression on T cells in RRMM and at treatment intervals in NDMM (as described earlier). The proportion of CD4+ and CD8+ T cells expressing PD-1 was increased 4-6 months post-ASCT and remained elevated in CD4+ T cells 9-12 months post-ASCT, but normalised to baseline levels in CD8+ T cells. Increased PD-1 expressing CD4+ T cells was also evident in RRMM patient samples. This may suggest that in the lymphopenic state, PD-1 expression enhances longevity in a subset of CD4+ T cells by promoting reliance on mitochondrial respiration; however, their ability to undergo homeostatic proliferation is impaired. In CD8+ T cells, high PD-1 expression may lead to cell death via ROS accumulation, and these cells do not persist. ASCT remains a backbone of myeloma treatment in medically fit patients. However, this leads to significant permanent defects in the T cell repertoire, which may have unintended adverse outcomes. Additionally, T cells post-ASCT may not be metabolically adequate for the production of CAR-T cells, nor respond to checkpoint blockade therapies. Disclosures Quach: Amgen: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Sanofi Genzyme: Research Funding; Janssen Cilag: Consultancy. Harrison:Janssen-Cilag: Other: Scientific advisory board. Prince:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees.

scholarly journals NLRP6 in Donor T Cells Separately Regulates CD4 and CD8 Mediated Graft-Versus-Host Disease in Experimental Murine BMT

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1926-1926
Author(s):  
Masahiro Suto ◽  
Eri Matsuki ◽  
Erika Sekiguchi ◽  
Hiroya Tamaki ◽  
Isao Tawara ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Research Funding ◽  
Pharmaceutical Research ◽  
T Cell Responses ◽  
Inflammasome Activation ◽  
Activated T Cells ◽  
Cell Responses ◽  
Donor T Cells

NLRP6 (NOD-like receptor family pyrin domain containing 6) is an important inflammasome component and is highly expressed in intestinal epithelial and in immune cells. NLRP6 mediated inflammasome activation plays a critical role in response to intestinal infection and preventing dysbiosis of gut microbiota through the secretion of IL-18 and mucus. However, we recently found that NLRP6 plays a pathogenic role in GVHD that is independent of microbial dysbiosis, which is in contrast to its well-appreciated microbiome-dependent protective role in intestinal colitis and tumorigenesis. Interestingly, we also found that activated T cells increased NLRP6 expression, but the T cell autonomousrole of NLRP6 in regulating T cell responses is unknown. Because NLRP6 is an important regulator of GVH responses, we tested the hypothesis that NLRP6 deficiency in donor T cells would ameliorate GVHD. To test our hypothesis, we first performed adetailed phenotypic analysis of various T cell subsets and activation markers in naïve NLRP6-/-and wild-type (WT) B6 animals and found a similar distribution of naïve, memory, effector and regulatory T cells. In order to examine whether the absence of NLRP6 in donors affects GVHD, WT-BALB/canimals were lethally irradiated (700cGy) and transplanted on day 0 with 5x106bone marrow and 1.0x106 splenic CD90+T cells from either syngeneic WT-BALB/c, allogeneic MHC-mismatched WT-B6 or NLRP6-/-animals. Contrary to our hypothesis, the recipients receiving donor T cells from NLRP6-/-animals showed a significantly worse survival compared to allogeneic WT-B6 animals (p<0.05). GVHD mortality and severity were also increased in an MHC mismatched B6 into B10.BR model, and in an MHC mismatched haploidentical B6 into F1model (p<0.05). In contrast, GVHD severity and mortality were similar in an MHC matched multiple minor antigen mismatched B6 into C3H.sw model. We hypothesized that GVHD severity and mortality was similar in the B6 into C3H.sw model because NLRP6 regulates CD4+ and CD8+ T cell responses, differently. In order to test this, we transplanted C3H.sw recipients as above except we infused either 1x106CD4+ or CD8+ T cells from B6-WT or NLRP6-/-animals. GVHD severity and mortality (P<0.05) were enhanced only when NLRP6-/-CD4+ T cells transplanted. We confirmed enhanced GVHD mortality and severity mediated by donor NLRP6-/-CD4+ T cells in a second MHC-mismatched GVHD model, B6 into BALB/c (p<0.05). To explore how NLRP6 effects T cell responses independent ofinflammasome activation, we tested naïve T cell proliferation in vitro after allogeneic or non-specific TCR stimulation by anti-CD3 and CD28 antibody and found that NLRP6-/-CD4+ but not CD8+T cells proliferated more than WT-B6 CD4+ or CD8+ T cells, respectively, following either stimulus. Furthermore, allogeneicNLRP6-/-T cells also caused greater mortality compared to WT allogenic T cells in a non-irradiated B6 into F1 model, which lacks inflammasome activation associated with conditioning induced DAMPs and PAMPs. Microarray analysis of activated T cells from NLRP6-/-animals showed higher expression of IL-2 and IFN-γ than WT B6 T cells, and we observed no effect of NLRP6 in a Treg suppression assay. These data suggest that NLRP6 regulates CD4+ T cell- mediated immune responses and that NLRP6 in donor T cells is critical for controlling CD4+ T cell mediated GVHD. The effect of NLRP6 on T cell mediated GVL is currently under investigation. Disclosures Tawara: Kyowa Hakko Kirin: Honoraria, Research Funding; Ono Pharmaceutical: Research Funding; Astellas Pharma: Research Funding. Ishizawa:Otsuka Pharmaceutical: Research Funding; Pfizer: Research Funding; Novartis: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau.

Dasatinib-Induced Reduction of Tumor Growth Is Accompanied By the Changes in the Immune Profile in a Melanoma B16.OVA Mouse Model

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1408-1408
Author(s):  
Mette Matilda Ilander ◽  
Can Hekim ◽  
Markus Vähä-Koskela ◽  
Paula Savola ◽  
Siri Tähtinen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Cd8 T Cells ◽  
Research Funding ◽  
K562 Cells ◽  
Cell Cytotoxicity ◽  
Cd8 Cells

Abstract Background: Dasatinib is a 2nd generation tyrosine kinase inhibitor (TKI) used in the treatment of chronic myeloid leukemia (CML). Its kinase inhibition profile is broad and includes several kinases important in the immune cell function such as SRC kinases. Furthermore, it is known that dasatinib has immunomodulatory effects in vivo. Recently, we observed that dasatinib induces a rapid and marked mobilization of lymphocytes, which closely follows the drug plasma concentration. The phenomenon is accompanied by an increase of NK-cell cytotoxicity. In addition, we have shown that dasatinib alters T-cell responses long-term favoring Th1 type of responses. Interestingly, the dasatinib induced immune effects have been associated with better treatment responses. We now aimed to characterize the dasatinib-induced antitumor immune responses in a syngeneic murine melanoma model to address whether dasatinib-induced immunoactivation affects tumor growth. Methods: Direct cytotoxic effect of dasatinib on B16.OVA melanoma cells in vitro was assessed with an MTS cell viability assay. T-cell cytotoxicity was assessed by preincubating splenocytes isolated from naïve and OT-I mouse spleen with 100 nM dasatinib and measured their cytotoxic capacity against B16.OVA cells. To further evaluate the dasatinib induced antitumor immune effects in vivo, B16.OVA cells were implanted subcutaneously in C57BL/6J mice. The mice (n=6/group) were treated daily i.g. either with 30 mg/kg dasatinib or vehicle only. Blood was collected before tumor transplantation, before treatment, and on treatment days 4, 7 and 11. Tumor volumes were measured manually and specific growth rate was calculated based on the first and the last day of the treatment. In addition to white blood cell differential counts, immunophenotyping of blood and tumor homogenate was performed by flow cytometry using antibodies against CD45.1, CD3, CD4, CD8b, NK1.1, CTLA4, PD-1 and CD107. Immunohistochemical staining of CD8+ T-cells was performed from the paraffin embedded tumor samples. Results: In vitro incubation of B16.OVA cells with dasatinib showed only a moderate unspecific cytotoxicity with the two highest concentrations of dasatinib (1- and 10 µM), whereas in K562 cells (a CML blast crisis cell line) almost complete killing was observed already with the 100nM concentration. The cell viability of B16.OVA cells was 90% with at 100 nM of dasatinib concentration (as compared to 21% of K562 cells) suggesting that there was no direct dasatinib sensitive target oncokinase in this cell line. In contrast, a significant enhancement in the cytotoxic capacity of splenocytes was observed when they were pretreated with 100nM dasatinib (60% of target cells were alive when incubated with dasatinib pretreated naïve splenocytes compared to 100% with control treated splenocytes, p=0.004). The in vivo tumor experiments demonstrated that the tumor volumes were smaller in dasatinib group, and there was a significant decrease in the specific tumor growth rate (0.06 vs. 0.18, p=0.01) on the 11th day of treatment. Interestingly, dasatinib treated mice had increased proportion of CD8+cells in the circulation (17.9% vs. 14.4%, p=0.005) and the CD4/CD8 ratio was significantly decreased (1.39 vs. 1.52, p= 0.04). During the tumor growth the mean CTLA-4 expression on CD8+ cells in PB increased from 1.2% to 9% in the control group, whereas, in dasatinib group the increase was more modest (1.2% to 5.7%). When the tumor content was analyzed, dasatinib treated mice had significantly more tumor infiltrated CD8+ T-cells (median 17 vs. 4/counted fields, p=0.03). In dasatinib group 80% of the tumor infiltrating CD8+ cells expressed PD-1 antigen compared to <5% of PD1 positive CD8+ cells in the peripheral blood suggesting either tumor induced CD8 T-cell exhaustion or the presence of tumor-reactive effector cells. Lastly, when CD4 and CD8 cells were depleted before tumor inoculation, dasatinib was no longer able to slow down the tumor growth. Conclusions: Dasatinib treatment slowed the tumor growth in a B16.OVA mouse model. The growth retardation was due to immunomodulatory properties of dasatinib as the drug was not directly cytotoxic and depletion of T-cells abolished the effect. Dasatinib may be a therapeutically useful immunomodulatory agent for targeting tumor-associated anergy, particularly in combination with novel checkpoint inhibitors and tumor-targeting drugs. Disclosures Hemminki: Oncos Therapeutics Ltd: Shareholder Other; TILT BioTherapeutics Ltd: Employment, Shareholder, Shareholder Other. Porkka:BMS and Novartis: Honoraria, Research Funding; Pfizer: Research Funding. Mustjoki:Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria, Research Funding.

scholarly journals Activation of naive and memory T cells by interleukin-15

Blood ◽  
1996 ◽  
Vol 88 (1) ◽  
pp. 230-235 ◽  
Author(s):  
H Kanegane ◽  
G Tosato
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Biological Activities ◽  
Growth Stimulation ◽  
T Cell Subsets ◽  
Beta Chain ◽  
Activated T Cells ◽  
Interleukin 15

Abstract Interleukin-15 (IL-15), a product of monocytes and other cells, has biological activities similar to those of IL-2, including growth stimulation of activated T cells, induction of cytolytic effector cells, and B-cell costimulation for proliferation and lg production. We report that IL-15 at optimal concentrations rapidly induced memory (CD45RO+) CD4+ and CD8+ T cells and naive (CD45RO-) CD8+ T cells to express the CD69 activation marker followed by proliferation. By contrast, IL-15 failed to induce naive (CD45RO-) CD4+ T cells to express CD69 or to proliferate. Similar findings were obtained with IL- 2. Unlike the other T-cell subsets, CD4+ T cells with a naive phenotype expressed little or no IL-2R beta chain, a shared component of the IL-2 and IL-15 receptors required for receptor function. A monoclonal antibody to the IL-2R beta chain, Mik beta 1, reduced CD69 expression and proliferation in CD4+ memory, CD8+ memory, and CD8+ naive T cells activated by IL-15. These results confirm the biological similarities of IL-2 and IL-15. They further document that the pool of naive CD4+ cells, unlike the pool of memory CD4+, memory CD8+, and naive CD8+ cells, is not regulated directly by the T-cell growth factors IL-2 or IL-15.

Detuning CD8+ T lymphocytes by down-regulation of the activating receptor NKG2D: role of NKG2D ligands released by activated T cells

Blood ◽  
2009 ◽  
Vol 113 (13) ◽  
pp. 2955-2964 ◽  
Author(s):  
Cristina Cerboni ◽  
Michele Ardolino ◽  
Angela Santoni ◽  
Alessandra Zingoni
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Cultures ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Γδ T Cells ◽  
Activated T Cells ◽  
Cell Functions ◽  
Major Player ◽  
Activating Receptor

Abstract NKG2D is an activating receptor expressed on CD8+αβ+ T cells, γδ+ T cells, natural killer (NK) cells, and some CD4+ T cells. For a long time, the interaction of NKG2D with its ligands (NKG2DLs) MICA, MICB, and ULBP1-3 has been considered a mechanism for recognition and elimination of tumor, infected, or otherwise “stressed” cells. However, a new role for NKG2D as an immunoregulatory receptor is emerging. Here, we show that NKG2D is strongly down-modulated on antigen-activated CD8+ T cells but only if CD4+ T cells are present. Down-modulation was caused by soluble factors produced by CD4+ T cells, and in particular soluble NKG2DLs were found in the supernatants of antigen-activated T-cell cultures. MICB was the ligand released at higher levels when CD4+ T cells were present in the cell cultures, suggesting that it could be the major player of NKG2D down-modulation. CD8+ T cells expressing low levels of NKG2D had impaired effector functions, as evaluated by proliferation, cytokine production, and cytotoxicity assays after combined triggering of NKG2D and TCR-CD3 complex. These findings show that activated CD4+ T cells expressing NKG2DLs can efficiently prevent NKG2D-mediated CD8+ T-cell functions, and suggest that the NKG2D/NKG2DL interaction can regulate immune responses.

scholarly journals Anti-PD-1/PD-L1 Based Combination Immunotherapy to Boost Antigen-Specific CD8+ T Cell Response in Hepatocellular Carcinoma

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1922
Author(s):  
Julia Peña-Asensio ◽  
Henar Calvo ◽  
Miguel Torralba ◽  
Joaquín Miquel ◽  
Eduardo Sanz-de-Villalobos ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cell Receptor ◽  
T Cell Response ◽  
Immune Checkpoints ◽  
Tumor Resistance ◽  
Cell Reactivity ◽  
Precursor Pool ◽  
Cd8 Cells

Thirty to fifty percent of hepatocellular carcinomas (HCC) display an immune class genetic signature. In this type of tumor, HCC-specific CD8 T cells carry out a key role in HCC control. Those potential reactive HCC-specific CD8 T cells recognize either HCC immunogenic neoantigens or aberrantly expressed host’s antigens, but they become progressively exhausted or deleted. These cells express the negative immunoregulatory checkpoint programmed cell death protein 1 (PD-1) which impairs T cell receptor signaling by blocking the CD28 positive co-stimulatory signal. The pool of CD8 cells sensitive to anti-PD-1/PD-L1 treatment is the PD-1dim memory-like precursor pool that gives rise to the effector subset involved in HCC control. Due to the epigenetic imprints that are transmitted to the next generation, the effect of PD-1 blockade is transient, and repeated treatments lead to tumor resistance. During long-lasting disease, besides the TCR signaling impairment, T cells develop other failures that should be also set-up to increase T cell reactivity. Therefore, several PD-1 blockade-based combinatory therapies are currently under investigation such as adding antiangiogenics, anti-TGFβ1, blockade of other negative immune checkpoints, or increasing HCC antigen presentation. The effect of these combinations on CD8+ T cells is discussed in this review.

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