scholarly journals Comparison of Exosomes Derived from Non- and Gamma-Irradiated Melanoma Cancer Cells as a Potential Antigenic and Immunogenic Source for Dendritic Cell-Based Immunotherapeutic Vaccine

Vaccines ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 699
Author(s):  
Woo Sik Kim ◽  
DaeSeong Choi ◽  
Ji Min Park ◽  
Ha-Yeon Song ◽  
Ho Seong Seo ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cancer Cells ◽  
Biologically Active ◽  
Host Cells ◽  
T Cell Proliferation ◽  
Melanoma Cancer ◽  
Ifn Γ ◽  
Gamma Irradiated

Cancer cells can secrete exosomes under various stressful conditions, whose functions are involved in the delivery of various biologically active materials into host cells and/or modulation of host immune responses. Therefore, an improved understanding of the immunological interventions that stress-induced tumor exosomes have may provide novel therapeutic approaches and more effective vaccine designs. Here, we confirmed the phenotypical and functional alterations of dendritic cells (DCs), which act as a bridge between the innate and adaptive arms of immunity, following non-irradiated (N-exo) and gamma-irradiated melanoma cancer cell-derived exosome (G-exo) stimulation, and evaluated the N-exo- and G-exo-stimulated DCs as therapeutic cancer vaccine candidates. We demonstrated that G-exo-stimulated DCs result in DC maturation by the upregulation of surface molecule expression, pro-inflammatory cytokine release, and antigen-presenting ability, and the downregulation of endocytic capacity. In addition, these cells promoted T cell proliferation and the generation of T helper type 1 (Th1) and interferon (IFN)-γ-producing CD8+ T cells. However, N-exo-stimulated DCs induced semi-mature phenotypes and functions, eventually inhibiting T cell proliferation, decreasing IFN-γ, and increasing IL-10-producing CD4+ T cells. In addition, although N-exo and G-exo stimulations showed similar levels of antigen-specific IFN-γ production, which served as tumor antigen sources in melanoma-specific T cells, G-exo-stimulated DC vaccination conferred a stronger tumor growth inhibition than N-exo-stimulated DC vaccination; further, this was accompanied by a high frequency of tumor-specific, multifunctional effector T cells. These results suggest that gamma irradiation could provide important clues for designing and developing effective exosome vaccines that can induce strong immunogenicity, especially tumor-specific multifunctional T cell responses.

scholarly journals The Role of Interleukin-10 (IL-10) in IL-15–Mediated T-Cell Responses

Blood ◽  
1997 ◽  
Vol 90 (11) ◽  
pp. 4513-4521 ◽  
Author(s):  
Dieter Körholz ◽  
Ursula Banning ◽  
Halvard Bönig ◽  
Markus Grewe ◽  
Marion Schneider ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Interleukin 10 ◽  
T Cell Proliferation ◽  
Cell Production ◽  
Cd25 Expression ◽  
Tnf Α ◽  
Ifn Γ

Abstract Interleukin-15 (IL-15) is a potent T-cell stimulating factor, which has recently been used for pre-clinical in vivo immunotherapy. Here, the IL-15 effect on CD3-stimulated peripheral human T cells was investigated. IL-15 induced a significant T-cell proliferation and upregulated CD25 expression. IL-15 significantly enhanced T-cell production of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and IL-10. Between 10- and 100-fold greater concentrations of IL-15 were necessary to reach a biological effect equivalent to that of IL-2. Blockade of IL-2 binding to the high-affinity IL-2 receptor did not affect the IL-15 effects, suggesting that IL-15 did not act by inducing endogenous IL-2. Exogenously administered IL-10 significantly reduced the IL-15 and IL-2–mediated IFN-γ and TNF-α production, whereas T-cell proliferation and CD25 expression were not affected. The inhibitory effects of exogenously administered IL-10 on T-cell cytokine production appeared indirect, and are likely secondary to decreased IL-12 production by accessory cells. Inhibition of endogenous IL-10 binding to the IL-10 receptor significantly increased IFN-γ and TNF-α release from T cells. These data suggest that endogenous IL-10 can regulate activated T-cell production of IFN-γ and TNF-α via a paracrine negative feedback loop. The observations of this study could be of relevance for the therapeutic use of IL-15 in vivo.

CD11b+gr-1+ myeloid Derived Suppressor Cells (MDSC) In Normal Bone Marrow Suppress T Cell Proliferation and Enhance T-Regulatory Function Via a IL10-, IL4- and IDO-Independent Mechanism

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4801-4801 ◽  
Author(s):  
Parvin Forghani ◽  
Wayne Harris ◽  
jian-Ming Li ◽  
M.R. Khorramizadeh ◽  
Edmund Waller
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Regulatory Function ◽  
T Cell Proliferation ◽  
Suppressive Activity ◽  
Ifn Γ

Abstract Abstract 4801 MDSC have been described as an important negative regulators of autologous anti-cancer immune responses. Considering the important role of MDSC in immune regulation in allogenic stem cell and organ transplantation, we undertook an investigation of the mechanism(s) by which MDSC inhibit T–cell activation and proliferation, and tested the hypothesis that local cytokine secretion or IDO activity is required for suppression of T-cell proliferation. Two separate populations CD11bhiGr-1hi and CD11bhi Gr-1int were isolated by high-speed FACS from lineage- BM antigen presenting cells (C57 & BALB/c mice). Both MDSC subsets had potent capacity for in–vitro suppression of CD4+ and CD8+ T cells proliferation in response to anti-CD3/anti-CD28 beads and Con A. A ratio of 0.5/1 MDSC: T-cells were sufficient to inhibit >66% control levels of T-cell proliferation. MDSC isolated from transgenic mice that had been “knocked-out” for IFN-γ and IDO had equivalent suppressive activity as MDSC from wild-type donors. Addition of saturating concentrations of anti IL-10 and IL-4 MAb, or in combination with anti- IFN-γ MAb did not abrogate MDSC-suppressive activity. Ex-vivo culture of MDSC with mitogen-activated T-cells generated two—fold more Fox-p3 T-reg compared with cultures of T cell plus mitogen. Data will be presented regarding the novel role of MDSC involving in the homeostasis regulation of normal T-cell activation and proliferation in non-tumor-bearing mice. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Compensation for Decreased Expression of B7 Molecules on Leishmania infantum-Infected Canine Macrophages Results in Restoration of Parasite-Specific T-Cell Proliferation and Gamma Interferon Production

1999 ◽  
Vol 67 (1) ◽  
pp. 237-243 ◽  
Author(s):  
Elena Pinelli ◽  
Victor P. M. G. Rutten ◽  
Martijn Bruysters ◽  
Peter F. Moore ◽  
E. Joost Ruitenberg
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Leishmania Infantum ◽  
Cell Activation ◽  
Gamma Interferon ◽  
T Cell Proliferation ◽  
B7 Molecules ◽  
Ifn Γ

ABSTRACT Infection of humans and dogs by Leishmania infantum may result in visceral leishmaniasis, which is characterized by impaired T-cell-mediated immune responses to parasite antigens. Dogs are natural hosts of Leishmania parasites and play an important role in the transmission of the parasites to humans. In an effort to characterize the immune response in dogs infected with this intracellular pathogen, we examined how infection with L. infantum affects canine macrophages and the consequences for T-cell activation in vitro. We showed that the proliferation of T-cell lines to cognate antigen decreases to background levels when infected autologous monocyte-derived macrophages are used as antigen-presenting cells (APC). The observed reduction of antigen-specific T-cell proliferation was shown to be dependent on the parasite load and to require cell-to-cell interaction of T cells with the infected APC. In addition, we observed a decreased expression of costimulatory B7 molecules on infected monocyte-derived macrophages. The expression of other surface molecules involved in T-cell activation, such as major histocompatibility complex class I and class II, on these cells did not change upon infection, whereas the expression of intracellular adhesion molecule 1 was marginally increased. Compensation for the decreased expression of B7 molecules by the addition of B7-transfected cells resulted in the restoration of cell proliferation and gamma interferon (IFN-γ) production by a Leishmania-specific T-cell line. These results showed that for the activation of parasite-specific canine T cells producing IFN-γ, which are most likely involved in protective immunity, sufficient expression of B7 molecules on infected macrophages is required. Provision of costimulatory molecules may be an approach for immunotherapy of leishmaniaisis as well as for vaccine development.

scholarly journals P03.02 Suppression of T-cell proliferation and cytokine release by the adenosine axis are mediated by different mechanisms

2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A22.2-A23
Author(s):  
J Festag ◽  
T Thelemann ◽  
M Schell ◽  
S Raith ◽  
S Michel ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Degradation Products ◽  
T Cell Proliferation ◽  
Activated T Cells ◽  
Human T Cells ◽  
Part Time ◽  
Ifn Γ ◽  
Cd73 Expression

BackgroundThe so-called adenosine axis has emerged as a promising therapeutic target pathway as high adenosine levels in the tumor microenvironment contribute to the suppression of antitumor immune responses. The ectonucleotidases CD39 and CD73 act in concert to degrade extracellular immune-stimulating adenosine triphosphate (ATP) to immunosuppressive adenosine. According to the current model, subsequent suppression of effector immune cell function is caused by binding of adenosine to adenosine receptors like the A2a receptor (A2aR). The ectonucleotidases CD39 and CD73 as well as the A2aR have emerged as molecular targets within the adenosine axis with currently more than 20 clinical trials investigating antitumor effects of CD39-, CD73- or A2aR blockade. We aimed to perform a direct comparison of these targets with regard to their roles in regulating T-cell proliferation and IFN-γ secretion.Materials and MethodsCD39 and CD73 expression was suppressed using LNAplusTM antisense oligonucleotides (ASOs). ASOs were synthesized as gapmers with flanking locked nucleic acids (LNA) to increase stability and affinity to the target RNA, leaving a central gap for recruitment of the RNA-degrading enzyme RNaseH I. Knockdown efficacy of ASOs on mRNA and protein level was investigated in primary human T cells. Furthermore, the effects of ATP, AMP and adenosine analogues on T–cell proliferation and IFN–γ secretion were investigated. A2aR was blocked using small molecule inhibitors that are currently under clinical investigation.ResultsTreatment of human T cells with LNA-modified ASOs specific for human CD39 and CD73 resulted in potent target knockdown in vitro without the use of a transfection reagent. T-cell proliferation was reduced after addition of ATP to activated T cells that was completely reverted by ASO-mediated suppression of CD39 and/or CD73 expression but not A2aR inhibition. Adenosine analogues inhibited IFN–γ secretion of activated T cells, however, they did not suppress T-cell proliferation. Blockade of the adenosine kinase was able to revert the anti-proliferative effect of ATP degradation products, arguing for downstream metabolites of adenosine, but not A2aR signaling, being responsible for the suppression of T-cell proliferation.ConclusionsCytokine secretion and proliferation of T cells might be differentially regulated by the adenosine axis. Adenosine might primarily affect cytokine secretion via A2aR signaling, whereas adenosine metabolites might especially impair proliferation of activated T cells independent from A2aR signaling. Therefore, inhibition of CD39 and/or CD73 holds exceptional advantages over A2aR blockade as both, A2aR dependent and A2aR independent effects of ATP degradation products are targeted simultaneously.Disclosure InformationJ. Festag: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG. T. Thelemann: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG. M. Schell: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG. S. Raith: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG. S. Michel: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG. R. Klar: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG. F. Jaschinski: A. Employment (full or part-time); Significant; Secarna Pharmaceuticals GmbH & Co. KG.

The role of SAP in murine CD150 (SLAM)-mediated T-cell proliferation and interferon γ production

Blood ◽  
2002 ◽  
Vol 100 (8) ◽  
pp. 2899-2907 ◽  
Author(s):  
Duncan Howie ◽  
Susumo Okamoto ◽  
Svend Rietdijk ◽  
Kareem Clarke ◽  
Ninghai Wang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Surface ◽  
Dna Synthesis ◽  
Interferon Γ ◽  
T Cell Proliferation ◽  
Wild Type ◽  
Ifn Γ

CD150 (signaling lymphocyte activation molecule [SLAM]) is a self-ligand cell surface glycoprotein expressed on T cells, B cells, macrophages, and dendritic cells. To further explore the role of CD150 signaling in costimulation and TH1 priming we have generated a panel of rat antimouse CD150 monoclonal antibodies. CD150 cell surface expression is up-regulated with rapid kinetics in activated T cells and lipopolysaccharide/interferon γ (IFN-γ)–activated macrophages. Anti-CD150 triggering induces strong costimulation of T cells triggered through CD3. DNA synthesis of murine T cells induced by anti-CD150 is not dependent on SLAM-associated protein (SAP, SH2D1A), because anti-CD150 induces similar levels of DNA synthesis in SAP−/− T cells. Antibodies to CD150 also enhance IFN-γ production both in wild-type and SAP−/− T cells during primary stimulation. The level of IFN-γ production is higher in SAP−/− T cells than in wild-type T cells. Anti-CD150 antibodies also synergize with interleukin 12 (IL-12) treatment in up-regulation of IL-12 receptor β2 mRNA during TH1 priming, and inhibit primary TH2 polarization in an IFN-γ–dependent fashion. Cross-linking CD150 on CD4 T cells induces rapid serine phosphorylation of Akt/PKB. We speculate that this is an important pathway contributing to CD150-mediated T-cell proliferation.

scholarly journals Let-7a Inhibits T-Cell Proliferation and IFN-γ Secretion by Down-Regulating STAT3 Expression in Patients with Psoriasis

2017 ◽  
Vol 42 (1) ◽  
pp. 115-125 ◽  
Author(s):  
Xiao-Ping Hu ◽  
Qian Xie ◽  
Chao-Feng Chen ◽  
Wei Zhang ◽  
Bo Yu
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Correlation Analysis ◽  
Mrna Expression ◽  
Pearson Correlation ◽  
T Cell Proliferation ◽  
Control Group ◽  
Pearson Correlation Analysis ◽  
Ifn Γ

Objective: This study aimed to explore the effects of STAT3 targeting by let-7a on T-cell proliferation and IFN-γ secretion in psoriasis. Methods: From January 2013 to January 2015, 40 patients with psoriasis (psoriasis group) and 38 volunteers undergoing plastic surgery (control group) were enrolled in this study. Pearson correlation analysis was performed to evaluate the correlation between let-7a and STAT3 expression. T-cells were isolated and subjected to different transfection methods. A dual luciferase reporter assay was carried out to confirm STAT3 as a target gene of let-7a. Let-7a, STAT3 and IFN-γ mRNA expression was detected by quantitative real-time fluorescent polymerase chain reaction (qRT-PCR), and pSTAT3 protein levels were determined by Western blot. T-cell proliferation was evaluated with a cell counting kit-8 (CCK-8) assay. Results: The level of STAT3 mRNA and pSTAT3 was higher, but let-7a expression was lower in the psoriasis group than the control group. Pearson correlation analysis indicated that STAT3 expression was negatively correlated with let-7a expression. T-cells transfected with inhibitors exhibited greater IFN-γ mRNA expression and T-cell proliferation than transfected T-cells and T-cells transfected with a non-sense sequence, while T-cells transfected with let-7a mimics exhibited lower IFN-γ mRNA expression and T-cell proliferation than transfected T-cells and T-cells transfected with a non-sense sequence. This suggested that siRNA-STAT3 could reverse the increase in IFN-y mRNA expression and T-cell proliferation induced by let-7a inhibitors. Conclusion: Our results demonstrated that let-7a inhibits T-cell proliferation and IFN-γ secretion by down-regulating STAT3 in psoriasis.

scholarly journals Low-Dose Decitabine Augments the Activation and Anti-Tumor Immune Response of IFN-γ+ CD4+ T Cells Through Enhancing IκBα Degradation and NF-κB Activation

2021 ◽  
Vol 9 ◽  
Author(s):  
Xiang Li ◽  
Liang Dong ◽  
Jiejie Liu ◽  
Chunmeng Wang ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Immune Response ◽  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Low Dose ◽  
T Cell Proliferation ◽  
Ifn Γ ◽  
Iκbα Degradation

BackgroundCD4+ T cells play multiple roles in controlling tumor growth and increasing IFN-γ+ T-helper 1 cell population could promote cell-mediated anti-tumor immune response. We have previously showed that low-dose DNA demethylating agent decitabine therapy promotes CD3+ T-cell proliferation and cytotoxicity; however, direct regulation of purified CD4+ T cells and the underlying mechanisms remain unclear.MethodsThe effects of low-dose decitabine on sorted CD4+ T cells were detected both in vitro and in vivo. The activation, proliferation, intracellular cytokine production and cytolysis activity of CD4+ T cells were analyzed by FACS and DELFIA time-resolved fluorescence assays. In vivo ubiquitination assay was performed to assess protein degradation. Moreover, phosphor-p65 and IκBα levels were detected in sorted CD4+ T cells from solid tumor patients with decitabine-based therapy.ResultsLow-dose decitabine treatment promoted the proliferation and activation of sorted CD4+ T cells, with increased frequency of IFN-γ+ Th1 subset and enhanced cytolytic activity in vitro and in vivo. NF-κB inhibitor, BAY 11-7082, suppressed decitabine-induced CD4+ T cell proliferation and IFN-γ production. In terms of mechanism, low-dose decitabine augmented the expression of E3 ligase β-TrCP, promoted the ubiquitination and degradation of IκBα and resulted in NF-κB activation. Notably, we observed that in vitro low-dose decitabine treatment induced NF-κB activation in CD4+ T cells from patients with a response to decitabine-primed chemotherapy rather than those without a response.ConclusionThese data suggest that low-dose decitabine potentiates CD4+ T cell anti-tumor immunity through enhancing IκBα degradation and therefore NF-κB activation and IFN-γ production.

In Vitro Expansion of CMV-Specific T Cells from CMV Seronegative Donors.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3927-3927
Author(s):  
Stephanie Verfuerth ◽  
Arnold R. Pizzey ◽  
Shoon-Ling C. Chow ◽  
Noha Chowdhry ◽  
Stephen Mackinnon
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cellular Therapy ◽  
T Cell Proliferation ◽  
Adoptive Cellular Therapy ◽  
Size Classes ◽  
Pulsed Dc ◽  
Ifn Γ

Abstract CMV infection is still a negative prognostic factor in hematopoietic stem cell transplantation, largely due to adverse effects of antiviral chemotherapy. Advances have been made in the development of adoptive cellular therapy for CMV with cell products derived from CMV seropositive donors. However no such cell products from CMV negative donors are currently available, although CMV negative recipients of CMV positive grafts bear the greatest risk of CMV induced morbidity and mortality. Mature DC are capable of inducing in vivo primary T cell responses. We used an in vitro culture system employing MoDC generated with GM-CSF and IL-4, pulsed with CMV lysate and matured with CD40L to induce primary immune responses to CMV. CMV-specific T cell proliferation measured by 3H-Thymidine uptake could be induced in some 6 to 9-day cultures, however, the success rate was very low, and T cells could usually not be kept alive after becoming activated. The addition of IL-15 to cultures after 7 days resulted in some improvement, although some non-CMV specific T cell proliferation in response to control lysate or in the absence of antigen also occurred in some cultures. IL-12 added to cultures from day 0 resulted in a short-term increase in T cell proliferation that was followed by increased cell death and was also not entirely CMV-specific. The real benefit of IL-15, alone or in combination with IL-12, was seen in 2-week cultures: In 6/7 cultures from different CMV seronegative donors counts of viable T cells (by trypan blue exclusion) increased up to 10-fold. Two cultures that were additionally set up with control lysate-pulsed DC to detect proliferation in response to non-CMV components of the antigen, confirmed CMV-specificity. CMV-specificity was also shown by T cell receptor (TCR) complement determining region (CDR) 3 spectratyping. TCR-BV(variable region β)-size class expression patterns across 23 BV families were very similar in pre-culture unstimulated T cells and in T cells stimulated with control lysate-pulsed DC for 2 weeks, showing the typical near-normal distribution of PCR product amongst the different size classes indicative of un-stimulated T cells. T cells co-cultured with CMV lysate-pulsed DC for 2 weeks produced very skewed spectratypes, indicative of oligoclonal T cell expansion in response to the antigen. The effect of IL-15 on T cell spectratypes from CMV antigen-driven cultures was tested using cells from another donor. With or without IL-15, post-culture spectratypes showed oligoclonal T cell expansions in the same BV families and size classes. However, despite their similar shapes, spectratypes from IL-5 containing cultures were skewed to a greater extent, possibly indicating a greater effect of IL-15 on already activated T cells. No CD8+ T cells specific for single immunodominant epitopes could be detected by staining with up to 5 different HLA-CMVpeptide-tetramers in culture output from 4/4 donors. In 1 of 2 cultures analyzed by cytokine secretion assay, a significant sub-population of T cells (1%), in CD4 positive and negative fractions, secreted IFN-γ in response to re-stimulation with CMV antigen. No IFN-γ secreting CMV-specific pre-cursor T cells were detected in fresh PBMC, as expected. Whilst further work is required to make generation of CMV specific T cells from CMV seronegative donors more reproducible and to ensure antigen-specificity, these preliminary data are encouraging for the future generation of CMV-specific T cells from CMV seronegative donors for adoptive cellular therapy.

scholarly journals Interleukin-2 and Loss of Immunity in Experimental Mycobacterium avium Infection

2002 ◽  
Vol 70 (1) ◽  
pp. 27-35 ◽  
Author(s):  
Stuart I. Mannering ◽  
Christina Cheers
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Mycobacterium Avium ◽  
Interleukin 2 ◽  
T Cell Proliferation ◽  
Steady Increase ◽  
Activation Markers ◽  
Ifn Γ

ABSTRACT Experimental infection of mice with a virulent strain of Mycobacterium avium leads to a slowly progressive disease, which we have previously shown culminates in loss of gamma interferon (IFN-γ) production by T lymphocytes and death of the animals approximately 40 weeks after infection. Here we investigated the changes in T-cell activation, the production of interleukin-2 (IL-2), and the response to IL-2 throughout M. avium infection as a possible explanation for this loss. We found that there is a steady increase in the percentage of T cells expressing activation markers right to the end of infection. However, in vivo T-cell proliferation, measured as a percentage of CD4+ and CD8+ cells incorporating 5-bromo-2′-deoxyuridine, initially increased but then remained constant. In the final stages of infection there was a decline in proliferation of activated (CD62L−) T cells. Since IL-2 is a major driver of T-cell proliferation, we asked whether this was due to loss of IL-2 responsiveness or production. However, CD25 (IL-2Rα) continued to be highly expressed in the terminal stages of infection, and although IL-2 production declined, addition of recombinant IL-2 to cultures could not rescue the final loss of IFN-γ production.

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