Mesenchymal Stem Cells Produce Nitric Oxide, a Key Molecule for T Cell Suppression, upon Interaction with Activated T Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2556-2556
Author(s):  
Kazuya Sato ◽  
Katsutoshi Ozaki ◽  
Iekuni Oh ◽  
Akiko Meguro ◽  
Reine Tatara ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Knockout Mice ◽  
No Synthase ◽  
T Cell Proliferation ◽  
No Production ◽  
Activated T Cells ◽  
T Cell Suppression ◽  
Cell Suppression

Abstract The molecular mechanisms by which mesenchymal stem cells (MSCs) suppress T cell proliferation are poorly understood, and whether a soluble factor plays a major role remains controversial. We demonstrated that nitric oxide (NO) is important for T cell suppression by MSCs (ASH 2005, 403a). Here we further demonstrate that the production of NO in the presence of MSCs is dependent on CD4 or CD8 T cells but not on CD19 B cells. MSCs inhibits B cell proliferation induced by LPS, suggesting that mechanisms of supppression by MSCs are different between T cells and B cells. Inducible NO synthase was exclusively detected in MSCs co-cultured with activated T cells, indicating that the producer of NO is MSC. Experiments with transwell system revealed that separation by transwell membrane reduces the induction of NO and T cell suppression. RAW246.7 macrophage cell line showed a similar transwell-mediated inhibition, suggesting that the inhibition by transwell is a common feature of NO and that direct contact is critical for efficient NO production and T cell suppression. Furthermore, inhibitors of prostaglandin synthase or NO synthase restored the proliferation of T cells, whereas an inhibitor of indoleamine 2,3-dioxygenase and a transforming growth factor-β-neutralizing antibody had no effect. In the view of that NO is upstream of PGE2, NO may be a key regulator of T cell suppression induced by MSCs. Finally, we used inducible NO synthase knockout mice to reconfirm all results here. MSCs from knockout mice did not produce NO even in the presence of activated wild type T cells and had a reduced ability to suppress T cell proliferation. Meanwhile, proliferation of splenocytes from knockout mice was suppressed in the presence of wild type MSCs and NO production was readily detected, confirming that NO produced by MSCs plays a critical role in T cell suppression.

Reciprocal Interaction Between Osteoclasts and T Cells: Osteoclasts Inhibit T Cell Proliferation by IDO Produced in Response to T Cell-Derived IFN-γ and CD40 Ligand

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 694-694
Author(s):  
Haiyan Li ◽  
Yong Lu ◽  
Sungyoul Hong ◽  
Jianfei Qian ◽  
Zhiqiang Liu ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cd40 Ligand ◽  
T Cell Proliferation ◽  
Activated T Cells ◽  
T Cell Suppression ◽  
Activated T Cell ◽  
Ifn Γ ◽  
Cell Suppression

Abstract Abstract 694 Osteoclasts (OCs), the responsible cells for bone resorption, are derived from monocytic precursor cells, with the stimulation of macrophage colony-stimulating factor (M-CSF) and the receptor activator of nuclear factor κb ligand (RANKL). The formation and activity of OCs can be either promoted by activated T cell derived RANKL, IL-17, or suppressed by T cell derived IFN-γ, IL-10, and IL-4. On the other hand, OCs express MHC, and costimulatory molecules, secrete IL-10, TGF-β, TNF-α and IL-6 and can act as antigen presenting cells to activate T cells, which indicates that OCs can be considered as immune cells. However, the immune function of OCs is largely unknown, and whether activated T cells can regulate the immune function of OCs is also unclear. In this study, we investigated the effect of OCs on T cell responses, and the cross regulation between activated T cells and immune regulatory OCs. Results showed that autologous OCs could inhibit the proliferation of CD4+ T cells activated by allogeneic antigen, tetanus toxin, staphylococcal enterotoxin B, and anti-CD3/CD28 antibodies. The inhibitory rate range varied from 63% to 88%. To identify the mechanism of OC-mediated T cell suppression, we blocked or inhibited TGF-β, IL-10, (prostaglandin E2) PGE-2, and indoleamine 2,3-dioxygenase (IDO) with neutralizing antibodies or specific inhibitors during the coculture. Results showed that only 1-methyl-DL-tryptophan (1-MT, an IDO inhibitor) could rescue the T cell proliferation, which suggested that OCs mediated the T cell suppression through IDO. To confirm this result, we knocked down IDO expression in OCs with siRNA and found that T cell proliferation was restored completely. As normal OCs didn't express IDO, next we investigated which molecules induced IDO expression in OCs, when cocultured with activated T cells. Results showed that blocking IFN-γ and CD40 ligand (CD40L) could inhibit IDO expression in OCs and rescue the T cell proliferation, and recombinant IFN-γ and soluble CD40L could induce IDO expression in OCs, synergistically. In conclusion, our study identified that OCs can function as immune regulatory cells to suppress T cell proliferation through IDO, which is induced by activated T cell derived IFN-γ and CD40L. This study provides new insight into the reciprocal interaction between OCs and T cells and may be helpful to develop novel therapeutic strategies for diseases involved in both bone and immune systems, such as bone-invasive tumors and autoimmune arthritis. Disclosures: No relevant conflicts of interest to declare.

Mesenchymal Stem Cells (MSCs) Suppress T Cell Proliferation by a Novel NO-stat5 Dependent Mechanism.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1393-1393
Author(s):  
Kazuya Sato ◽  
Katsutoshi Ozaki ◽  
Iekuni Oh ◽  
Keiko Hatanaka ◽  
Tadashi Nagai ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Molecular Mechanisms ◽  
T Cell Proliferation ◽  
Cd8 Cells ◽  
T Cell Suppression ◽  
Cell Suppression ◽  
Dependent Mechanism

Abstract Mesenchymal stem cells (MSCs) are attractive source for regenerative therapy as they have been shown to be capable of differentiating into adipocytes, chondrocytes, osteoblasts, myocytes, cardiomyocytes, and neural precursors. MSCs have also been shown to suppress T cell proliferation in vitro and were reported to be effective as a treatment for acute graft-versus-host disease (GVHD) but the underlying molecular mechanisms for T cell suppression are uncertain. So far, TGF-β, HGF, and PGE2 were shown to be candidates as molecules causing the suppression. To address the molecular mechanisms, we used primary mouse MSCs derived from bone marrow cells and CFSE (carboxyfluorescein diacetate succinimidyl ester) or thymidine uptake for T cell proliferation assay. Co-culture of MSCs inhibited T cell proliferation induced by PMA plus Ionomycin, suggesting that TCR and signaling molecules interacting with TCR such as Lck and ZAP70 are not involved and that downstream signals of PMA plus Ionomycin are essential for the suppression by MSCs. The proliferation of either purified CD4 or CD8 cells induced by PMA plus Ionomycin was also inhibited by co-culture with MSCs, indicating MSCs suppression is active on both CD4 and CD8 cells. Stat5 phosphorylation in activated T cells was suppressed by co-culture with MSCs. Induction of cell-cycle promoting proteins such as CDK6, Cyclin D2, and Cyclin E by mitogenic stimulation were inhibited and suppression of a cell-cycle inhibitor, Kip1, was abolished. A previous report showed that T cells from stat5 deficient mice failed to induce cell-cycle promoting proteins and were not be able to proliferate on the stimulation through TCR. It was also reported that Nitric Oxide (NO) suppressed stat5 phosphorylation. Taken together with these reports, we hypothesized that NO is another candidate for the cause of suppression. In fact, NO synthase inhibitor (N-nitro-L-arginine methyl ester) recovered T cell proliferation from the suppression by MSCs in a dose-dependent manner. The amount of NO production and the strength of T cell suppression were parallel and dependent on the number of MSCs. MSCs blocked production of IFNγ but induction of T cell activation markers such as CD25 and CD69 and production of IL-2 were unaffected as reported. Our data suggest that MSCs block stat5 phosphorylation by production of NO, resulting in that T cells can neither proliferate nor produce high level of IFNγ. Here we demonstrate a new critical NO-stat5 dependent mechanism for T cell suppression by MSCs.

scholarly journals Neutrophils Lose the Capacity to Suppress T Cell Proliferation Upon Migration Towards Inflamed Joints in Juvenile Idiopathic Arthritis

2022 ◽  
Vol 12 ◽  
Author(s):  
Sabine Arve-Butler ◽  
Anki Mossberg ◽  
Tobias Schmidt ◽  
Charlotte Welinder ◽  
Hong Yan ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Synovial Fluid ◽  
Suppressive Effect ◽  
T Cell Proliferation ◽  
Cell Contact ◽  
Ros Production ◽  
T Cell Suppression ◽  
Cell Suppression

Neutrophils are highly abundant in synovial fluid of rheumatic inflamed joints. In oligoarticular juvenile idiopathic arthritis (JIA), synovial fluid neutrophils have impaired effector functions and altered phenotype. We hypothesized that these alterations might impact the immunoregulatory interplay between neutrophils and T cells. In this study we analyzed the suppressive effect of neutrophils, isolated from blood and synovial fluid of oligoarticular JIA patients, on CD4+ T cells activated by CD3/CD28 stimulation. JIA blood neutrophils suppressed T cell proliferation but synovial fluid neutrophils from several patients did not. The loss of T cell suppression was replicated in an in vitro transmigration assay, where healthy control neutrophils migrated into synovial fluid through transwell inserts with endothelial cells and synoviocytes. Non-migrated neutrophils suppressed proliferation of activated CD4+ T cells, but migrated neutrophils had no suppressive effect. Neutrophil suppression of T cells was partly dependent on reactive oxygen species (ROS), demonstrated by impaired suppression in presence of catalase. Migrated neutrophils had reduced ROS production compared to non-migrated neutrophils. A proteomic analysis of transwell-migrated neutrophils identified alterations in proteins related to neutrophil ROS production and degranulation, and biological processes involving protein transport, cell-cell contact and inflammation. In conclusion, neutrophils in synovial fluid of children with JIA have impaired capacity to suppress activated T cells, which may be due to reduced oxidative burst and alterations in proteins related to cell-cell contact and inflammation. The lack of T cell suppression by neutrophils in synovial fluid may contribute to local inflammation and autoimmune reactions in the JIA joint.

Hyaluronidase and IFN-γ from Activated T-Cells Are Key Mediators To Induce Immunosuppressive Activity of Mesenchymal Stem Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3246-3246
Author(s):  
Kazuya Sato ◽  
Ozaki Katsutoshi ◽  
Iekuni Oh ◽  
Haruko Matsu ◽  
Raine Tatara ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Inos Expression ◽  
T Cell Proliferation ◽  
No Production ◽  
Immunosuppressive Activity ◽  
Activated T Cells ◽  
Ifn Γ

Abstract Mesenchymal stem cells (MSC) have been shown to suppress T-cell proliferation in vitro and are being clinically applied to treatment for steroid-refractory graft-versus-host disease (GVHD). However, the molecular mechanisms of immunosuppressive activity of MSC have not been fully understood. We have recently reported that nitric oxide (NO) is one of the key molecules for T-cell suppression by MSC (Blood, 2007;228–34). Inducible NO synthase (iNOS) expression in MSC and NO production were exclusively detected upon interaction with activated T-cells. An inhibitor of NOS restored the proliferation of T-cells. We have also shown that both IFN-γ and NF-κB mediate NO production by MSC (BBRC, 2007;80–90), however the factor(s) from T-cells that induce immunosuppressive activity of MSC have not been elucidated. In the present study, we focused on hyaluronic acid (HA), a major extracellular matrix component, because low molecular weight (LMW) HA is known to play an essential role in regulation of inflammation and infection, HA induces NOS in macrophages through a NF-κB-dependent mechanism, and T-cells are reported to express hyaluronidase-2 mRNA after activation. A series of such information suggests that activated T-cells regulate immunosuppressive activity of MSC through HA signaling. We investigated the molecular events in the interaction between MSC and activated T-cells, and demonstrated that HA may play an important role in the scenario. First, ELISA showed that MSC produce a large amount of HA. RT-PCR revealed that among three hyaluronic acid synthase (HAS), mRNA for HAS-1 but neither HAS-2 nor HAS-3 is constitutively expressed by MSC. Flow cytometric analysis also showed that MSC express CD44, one of the receptors for HA. In macrophages, either IFN-γ or LMW HA is known to induce NO production. Therefore, we investigated whether IFN-γ or LMW HA can induce NO production via NF-κB signaling in MSC. As a result, only in the presence of IFN-γ, LMW HA but not high molecular weight (HMW) HA induced expression of iNOS in MSC, followed by NO production from MSC. We found that prostaglandin E2 (PGE2), which was previously reported as another immunosuppressive factor of MSC, is also induced by the combination of IFN-γ and LMW HA. Since hyaluronidase activity in activated T-cells has already been reported, these data support a novel hypothesis that HMW HA produced by MSC is digested by hyaluronidase from activated T-cells, and that resultant LMW HA cooperates with IFN-γ from activated T-cells in inducing iNOS expression in MSC. Locally produced NO through the above mechanisms may suppress activated T-cell proliferation. These findings would be important to further potentiate and regulate the immunomodulatory activity of MSC in a variety of applications.

scholarly journals Defective interleukin-2 production and responsiveness by T cells in patients with chronic lymphocytic leukemia of B cell variety

Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 279-284 ◽  
Author(s):  
O Ayanlar-Batuman ◽  
E Ebert ◽  
SP Hauptman
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Chronic Lymphocytic Leukemia ◽  
B Cell ◽  
Proliferative Response ◽  
Interleukin 2 ◽  
Lymphocytic Leukemia ◽  
T Cell Proliferation ◽  
Activated T Cells

Abstract The present studies were designed to investigate the mechanism(s) of the defective T cell proliferative response to various stimuli in patients with B cell chronic lymphocytic leukemia B-CLL. In 14 patients with advanced B-CLL (stage III or IV) we found the T cell response in the autologous (auto) and allogeneic (allo) mixed lymphocyte reaction (MLR) to be 35.7% and 30% of the controls, respectively. Proliferation in the MLR depends upon the production of and response to interleukin 2 (IL 2), a T cell growth factor. IL 2 production in eight B-CLL patients was 22% of the control. The response to IL 2 was measured by the increase in the T cell proliferation in the MLR with the addition of IL 2. T cell proliferation in both the auto and allo MLR of CLL patients was significantly lower than in the controls after the addition of IL 2. The proliferative response of normal T cells to stimulation by CLL B cells was 50% of the control. This latter response was increased to control levels when cultures were supplemented with exogenous IL 2, suggesting that CLL B cells could stimulate IL 2 receptor generation in normal T cells in an allo MLR, but not IL 2 production. The presence of IL 2 receptors on activated T cells was directly determined using anti- Tac, a monoclonal antibody with specificity for the IL 2 receptor. Of the mitogen- or MLR-activated T cells in CLL patients, 6% and 10%, respectively, expressed Tac antigen, whereas identically stimulated control T cells were 60% and 47% Tac+, respectively. Our findings suggest that T cells in B-CLL are defective in their recognition of self or foreign major histocompatibility antigens as demonstrated by their impaired responsiveness in the MLR. Thus, these cells are unable to produce IL 2 or generate IL 2 receptors.

scholarly journals Fas-Independent Apoptosis of Activated T Cells Induced by Antibodies to the HLA Class I α1 Domain

Blood ◽  
1997 ◽  
Vol 90 (9) ◽  
pp. 3629-3639 ◽  
Author(s):  
Laurent Genestier ◽  
Romain Paillot ◽  
Nathalie Bonnefoy-Berard ◽  
Geneviéve Meffre ◽  
Monique Flacher ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Heavy Chain ◽  
Hla Class I ◽  
Class I ◽  
T Cell Proliferation ◽  
Activated T Cells ◽  
Hla Class I Molecules

Abstract In addition to their major function in antigen presentation and natural killer cell activity regulation, HLA class I molecules may modulate T-cell activation and proliferation. Monoclonal antibodies (MoAbs) that recognize distinct epitopes of HLA class I molecules were reported to interfere with T-cell proliferation. We show here that two MoAbs (mouse MoAb90 and rat YTH862) that bind to an epitope of the α1 domain of HLA class I heavy chain induce apoptotic cell death of activated, but not resting, peripheral T lymphocytes. Other reference anti-HLA class I antibodies specific for distinct epitopes of the α1 (B9.12.1), α2 (W6/32), or α3 (TP25.99) domains of the heavy chain decreased T-cell proliferation but had little or no apoptotic effect. Apoptosis shown by DNA fragmentation, phosphatidylserine externalization, and decrease of mitochondrial transmembrane potential was observed whatever the type of T-cell activator. Apoptosis did not result from Fas/Fas-L interaction and distinct though partly overlapping populations of activated T cells were susceptible to Fas– and HLA class I–mediated apoptosis, respectively. Induction of apoptosis did not require HLA class I cross-linking inasmuch as it could be observed with monovalent Fab′ fragments. The data indicate that MoAb90 and YTH862 directed against the α1 domain of HLA class I trigger apoptosis of activated T lymphocytes by a pathway which does not involve Fas-ligand.

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.

scholarly journals C-Jun Nh2-Terminal Kinase (Jnk)1 and Jnk2 Have Similar and Stage-Dependent Roles in Regulating T Cell Apoptosis and Proliferation

2001 ◽  
Vol 193 (3) ◽  
pp. 317-328 ◽  
Author(s):  
Kanaga Sabapathy ◽  
Tuula Kallunki ◽  
Jean-Pierre David ◽  
Isabella Graef ◽  
Michael Karin ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Interleukin 2 ◽  
Binding Activity ◽  
T Cell Proliferation ◽  
Activated T Cells ◽  
T Cell Function ◽  
Thymocyte Apoptosis

Apoptotic and mitogenic stimuli activate c-Jun NH2-terminal kinases (JNKs) in T cells. Although T cells express both JNK1 and JNK2 isozymes, the absence of JNK2 alone can result in resistance to anti-CD3–induced thymocyte apoptosis and defective mature T cell proliferation. Similar defects in thymocyte apoptosis and mature T cell proliferation, the latter due to reduced interleukin 2 production, are also caused by JNK1 deficiency. Importantly, T cell function was compromised in Jnk1+/−Jnk2+/− double heterozygous mice, indicating that JNK1 and JNK2 play similar roles in regulating T cell function. The reduced JNK dose results in defective c-Jun NH2-terminal phosphorylation in thymocytes but not in peripheral T cells, in which nuclear factors of activated T cells (NK-ATs)–DNA binding activity is affected. Thus, JNK1 and JNK2 control similar functions during T cell maturation through differential targeting of distinct substrates.

Sign in / Sign up

Export Citation Format

Share Document