Proteasome Inhibitors Affect the Function of Human Dendritic Cells and Induce Caspase-Mediated Apoptosis.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2229-2229
Author(s):  
Karin von Schwarzenberg ◽  
Alessio Nencioni ◽  
Anita Bringmann ◽  
Lothar Kanz ◽  
Franco Patrone ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Proteasome Inhibitors ◽  
Human Monocyte ◽  
Proteasome Inhibition ◽  
Parp Cleavage ◽  
Induced Apoptosis ◽  
And Function ◽  
Human Dendritic Cells

Abstract Proteasome inhibitors (PI) show antitumor activity against a broad spectrum of human malignancies both in vitro and in vivo. Yet, the consequences of exposure to these compounds on the immune system still have to be clearly determined. In the present study, we have investigated the effect of the proteasome inhibitors on human monocyte-derived dendritic cells (DCs). Exposure to PI results in a reduced activation induced DC maturation and cytokine production, inhibition of their migratory capacity and impaired ability to stimulate T-cell responses. These functional and phenotypic alterations were paralleled by a decreased phosphorylation of the MAP kinase member ERK1/2 while not affecting p38. Furthermore, incubation of DC with bortezomib inhibited the expression of nuclear localized transcription factors that were shown to be important for DC differentiation and function like IRF3, Rel-b and c-rel. Addition of PI to culture medium induced apoptosis of differentiated DCs and strongly reduced the yield of viable DCs when given to monocytes before differentiation to DCs was induced. DC apoptosis was accompanied by caspase activation as detected by caspase-3 and PARP cleavage. Cytochrome c cytosolic relocalization was detectable following exposure to bortezomib and was not prevented by caspase inhibition. This points to the mitochondrial damage as to an upstream event in DC apoptosis via proteasome inhibition. While not affecting Bcl-2 levels, bortezomib was found to promote Bax upregulation in DCs, thus providing a possible explanation for mitochondria dysfunction in response to this compound. In conclusion, this study shows that besides the inhibition of Nf-kB bortezomib is affecting several other pivotal signal transduction pathways in human cells and suggests that inhibition of DC function and induction of apoptosis in DCs may represent a mechanism by which bortezomib can affect the immune responses in patients treated with this compound.

scholarly journals Effects of Staphylococcus aureus Bacteriophage K on Expression of Cytokines and Activation Markers by Human Dendritic Cells In Vitro

Viruses ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 617 ◽  
Author(s):  
Helen Freyberger ◽  
Yunxiu He ◽  
Amanda Roth ◽  
Mikeljon Nikolich ◽  
Andrey Filippov
Keyword(s):  
Staphylococcus Aureus ◽  
Dendritic Cells ◽  
Inflammatory Response ◽  
Adaptive Immune Response ◽  
Human Monocyte ◽  
Activation Markers ◽  
Mhc I ◽  
Adaptive Immune ◽  
Human Dendritic Cells

A potential concern with bacteriophage (phage) therapeutics is a host-versus-phage response in which the immune system may neutralize or destroy phage particles and thus impair therapeutic efficacy, or a strong inflammatory response to repeated phage exposure might endanger the patient. Current literature is discrepant with regard to the nature and magnitude of innate and adaptive immune response to phages. The purpose of this work was to study the potential effects of Staphylococcus aureus phage K on the activation of human monocyte-derived dendritic cells. Since phage K acquired from ATCC was isolated around 90 years ago, we first tested its activity against a panel of 36 diverse S. aureus clinical isolates from military patients and found that it was lytic against 30/36 (83%) of strains. Human monocyte-derived dendritic cells were used to test for an in vitro phage-specific inflammatory response. Repeated experiments demonstrated that phage K had little impact on the expression of pro- and anti-inflammatory cytokines, or on MHC-I/II and CD80/CD86 protein expression. Given that dendritic cells are potent antigen-presenting cells and messengers between the innate and the adaptive immune systems, our results suggest that phage K does not independently affect cellular immunity or has a very limited impact on it.

scholarly journals Inhibition of O-GlcNAc Transferase Alters the Differentiation and Maturation Process of Human Monocyte Derived Dendritic Cells

Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3312
Author(s):  
Matjaž Weiss ◽  
Marko Anderluh ◽  
Martina Gobec
Keyword(s):  
Dendritic Cells ◽  
Posttranslational Modification ◽  
Human Monocyte ◽  
T Cell Differentiation ◽  
Maturation Process ◽  
Hla Dr ◽  
Glcnac Transferase ◽  
And Function

The O-GlcNAcylation is a posttranslational modification of proteins regulated by O-GlcNAc transferase (OGT) and O-GlcNAcase. These enzymes regulate the development, proliferation and function of cells, including the immune cells. Herein, we focused on the role of O-GlcNAcylation in human monocyte derived dendritic cells (moDCs). Our study suggests that inhibition of OGT modulates AKT and MEK/ERK pathways in moDCs. Changes were also observed in the expression levels of relevant surface markers, where reduced expression of CD80 and DC-SIGN, and increased expression of CD14, CD86 and HLA-DR occurred. We also noticed decreased IL-10 and increased IL-6 production, along with diminished endocytotic capacity of the cells, indicating that inhibition of O-GlcNAcylation hampers the transition of monocytes into immature DCs. Furthermore, the inhibition of OGT altered the maturation process of immature moDCs, since a CD14medDC-SIGNlowHLA-DRmedCD80lowCD86high profile was noticed when OGT inhibitor, OSMI-1, was present. To evaluate DCs ability to influence T cell differentiation and polarization, we co-cultured these cells. Surprisingly, the observed phenotypic changes of mature moDCs generated in the presence of OSMI-1 led to an increased proliferation of allogeneic T cells, while their polarization was not affected. Taken together, we confirm that shifting the O-GlcNAcylation status due to OGT inhibition alters the differentiation and function of moDCs in in vitro conditions.

scholarly journals In Vitro and In Vivo Effects of Ketamine on Generation and Function of Dendritic Cells

2011 ◽  
Vol 117 (3) ◽  
pp. 170-179 ◽  
Author(s):  
Jingxian Zeng ◽  
Shuxuan Xia ◽  
Wa Zhong ◽  
Jie Li ◽  
Liling Lin
Keyword(s):  
Dendritic Cells ◽  
And Function ◽  
In Vivo Effects

scholarly journals Pasteurella multocida Toxin Activates Human Monocyte-Derived and Murine Bone Marrow-Derived Dendritic Cells In Vitro but Suppresses Antibody Production In Vivo

2005 ◽  
Vol 73 (1) ◽  
pp. 413-421 ◽  
Author(s):  
Kenneth C. Bagley ◽  
Sayed F. Abdelwahab ◽  
Robert G. Tuskan ◽  
George K. Lewis
Keyword(s):  
Bone Marrow ◽  
Dendritic Cells ◽  
Phospholipase C ◽  
Cholera Toxin ◽  
Pasteurella Multocida ◽  
Human Monocyte ◽  
Mouse Bone Marrow ◽  
Dependent Manner

ABSTRACT Pasteurella multocida toxin (PMT) is a potent mitogen for fibroblasts and osteoblastic cells. PMT activates phospholipase C-β through Gqα, and the activation of this pathway is responsible for its mitogenic activity. Here, we investigated the effects of PMT on human monocyte-derived dendritic cells (MDDC) in vitro and show a novel activity for PMT. In this regard, PMT activates MDDC to mature in a dose-dependent manner through the activation of phospholipase C and subsequent mobilization of calcium. This activation was accompanied by enhanced stimulation of naïve alloreactive T cells and dominant inhibition of interleukin-12 production in the presence of saturating concentrations of lipopolysaccharide. Surprisingly, although PMT mimics the activating effects of cholera toxin on human MDDC and mouse bone marrow-derived dendritic cells, we found that PMT is not a mucosal adjuvant and that it suppresses the adjuvant effects of cholera toxin in mice. Together, these results indicate discordant effects for PMT in vitro compared to those in vivo.

The Fusarium toxin deoxynivalenol disrupts phenotype and function of monocyte-derived dendritic cells in vivo and in vitro

Immunobiology ◽  
2007 ◽  
Vol 212 (8) ◽  
pp. 655-666 ◽  
Author(s):  
D BIMCZOK ◽  
S DOLL ◽  
H RAU ◽  
T GOYARTS ◽  
N WUNDRACK ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Fusarium Toxin ◽  
And Function

scholarly journals DC-SIGN Is the Major Mycobacterium tuberculosis Receptor on Human Dendritic Cells

2002 ◽  
Vol 197 (1) ◽  
pp. 121-127 ◽  
Author(s):  
Ludovic Tailleux ◽  
Olivier Schwartz ◽  
Jean-Louis Herrmann ◽  
Elisabeth Pivert ◽  
Mary Jackson ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Mycobacterium Tuberculosis ◽  
Human Monocyte ◽  
Mannose Receptor ◽  
Intercellular Adhesion Molecule ◽  
Minor Role ◽  
Hla Dr ◽  
A Minor ◽  
Human Dendritic Cells

Early interactions between lung dendritic cells (LDCs) and Mycobacterium tuberculosis, the etiological agent of tuberculosis, are thought to be critical for mounting a protective anti-mycobacterial immune response and for determining the outcome of infection. However, these interactions are poorly understood, at least at the molecular level. Here we show that M. tuberculosis enters human monocyte-derived DCs after binding to the recently identified lectin DC-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN). By contrast, complement receptor (CR)3 and mannose receptor (MR), which are the main M. tuberculosis receptors on macrophages (Mϕs), appeared to play a minor role, if any, in mycobacterial binding to DCs. The mycobacteria-specific lipoglycan lipoarabinomannan (LAM) was identified as a key ligand of DC-SIGN. Freshly isolated human LDCs were found to express DC-SIGN, and M. tuberculosis–derived material was detected in CD14−HLA-DR+DC-SIGN+ cells in lymph nodes (LNs) from patients with tuberculosis. Thus, as for human immunodeficiency virus (HIV), which is captured by the same receptor, DC-SIGN–mediated entry of M. tuberculosis in DCs in vivo is likely to influence bacterial persistence and host immunity.

scholarly journals Differentiation and function of human monocyte-derived dendritic cells under the influence of leflunomide

2011 ◽  
Vol 63 (2) ◽  
pp. 353-364
Author(s):  
Z. Stojic-Vukanic ◽  
M. Colic ◽  
A. Backovic ◽  
J. Antic-Stankovic ◽  
B. Bufan ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Flow Cytometric Analysis ◽  
Human Monocyte ◽  
Surface Expression ◽  
Immunosuppressive Drugs ◽  
Experimental Models ◽  
Immunosuppressive Drug ◽  
Adhesive Molecules ◽  
And Function

Leflunomide is an immunosuppressive drug effective in experimental models of transplantation and autoimmune diseases and in the treatment of active rheumatoid arthritis (RA). Having in mind that it has been shown that some other immunosuppressive drugs (glucocorticoids, mycophenolate mofetil, sirolimus etc.) impair dendritic cell (DC) phenotype and function, we investigated the effect of A77 1726, an active metabolite of leflunomide, on the differentiation and function of human monocyte-derived dendritic cells (MDDC) in vitro. Immature MDDC were generated by cultivating monocytes in medium supplemented with GM-CSF and IL-4. To induce maturation, immature MDDC were cultured for 2 additional days with LPS. A77 1726 (100 ?M) was added at the beginning of cultivation. Flow cytometric analysis showed that MDDC differentiated in the presence of A77 1726 exhibited an altered phenotype, with a down-regulated surface expression of CD80, CD86, CD54 and CD40 molecules. Furthermore, the continuous presence of A77 1726 during differentiation and maturation prevented successful maturation, judging by the decreased expression of maturation marker CD83, costimulatory and adhesive molecules on A77 1726-treated mature MDDC. In addition, A77 1726-pretreated MDDC exhibited a poor stimulatory capacity of the allogeneic T cells and a low production of IL-10 and IL-18. These data suggest that leflunomide impairs the differentiation, maturation and function of human MDDC in vitro, which is an additional mechanism of its immunosuppressive effect.

Proteasome Inhibitor Combination with Cytarabine or Arsenic Trioxide Can Potentiate Apoptosis in AML Cells.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 4464-4464 ◽  
Author(s):  
Jane L. Liesveld ◽  
Camille N. Abboud ◽  
Chaohui Lu ◽  
Jeremy Bechelli ◽  
Karen Rosell ◽  
...  
Keyword(s):  
Arsenic Trioxide ◽  
Cell Lines ◽  
Proteasome Inhibitors ◽  
Proteasome Inhibition ◽  
Hl60 Cell ◽  
Parp Cleavage ◽  
Primary Cells ◽  
Inhibition Of Proliferation ◽  
Phosphorylated Akt

Abstract Proteasome inhibitors block degradation of the NF-κB regulator, IκB, resulting in inhibition of NF-κB nuclear localization. Proteasome inhibitors have been tested in the setting of refractory acute leukemia, with proteasome inhibition demonstrated within leukemic blasts. Arsenic trioxide (AsO3) has also been shown to inhibit NF-κB in leukemia. Since NF-κB is constitutively activated in primitive AML cells and serves as a regulator of many genes which encode proliferative and survival responses, we have begun to explore the effects of AsO3 and bortezomib (PS-341, VelcadeTM ), on AML cell lines and primary cells. The farnesyl transferase inhibitors (FTIs) also inhibit AML proliferation, and their effects in combination with bortezomib have also been explored. Because FTIs may inhibit signal transduction pathways independent of those affected by NF-κB inhibition, and because FTIs may indirectly inhibit NF-κB function via Akt inhibition, the effects of combining these agents with other NF-κB agents on AML cells in vitro have also been explored. Bortezomib, at concentrations of 4nM or greater, inhibited NF-κB in AML cell lines and primary cells as did AsO3 at concentrations of 1 nM or greater. NF-kappa B was measured by ELISA for p65 NF-κB activity. The nonpeptidomimetic FTI, R115777 (J&J), did not inhibit NF-κB at concentrations up to 100 nM, concentrations which effectively inhibit farnesylation of target proteins, whereas the FTI, L-744832 (Merck), was able to inhibit NF-κB expression at 1 μM from 24 to 72 hours of exposure. In the HL60 cell line, inhibited by FTI and bortezomib independently, the combination did not appear to have additive or synergistic effects. Furthermore, the effects of combined exposure to FTI and bortezomib on expression of activated caspase 3 or activated PARP cleavage were no greater than with bortezomib alone. Likewise, combination effects on expression of phosphorylated AKT or ERK were not observed. In contrast, the combination of bortezomib and AsO3 resulted in decreased phospho-ERK expression and increased expression of cleaved PARP, suggesting increased apoptosis. When cytarabine, 100 nM was combined with bortezomib at 1 to 4 nM, no effect on timing of administration was noted, and apoptosis was increased with the combination as evidenced by an increase in cleaved PARP expression. Greater inhibition of proliferation was seen with this combination than with individual agents as demonstrated in MTT assays with combination index calculations suggesting synergism. With this combination, co-culture with an endothelial monolayer did not prevent the increased apoptosis noted with combined cytarabine and bortezomib. These studies suggest that future studies combining proteasome inhibition with standard chemotherapeutic agents or with other inhibitors of NF-κB like Arsenic trioxide may have greater antileukemic activity by inducing apoptosis in AML cells in vivo as well as in vitro, without obvious limitations of other targeted agents and drugs that are extruded by multridrug resistance transporters.

Human Monocyte-Derived Dendritic Cells Are Tolerogenic through Both IDO1 and IDO2

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4298-4298
Author(s):  
Sara Trabanelli ◽  
Antonio Curti ◽  
Darina Očadlíková ◽  
Cecilia Evangelisti ◽  
Valentina Salvestrini ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Dendritic Cells ◽  
T Cell ◽  
Critical Role ◽  
Human Monocyte ◽  
Kynurenine Pathway ◽  
T Cell Proliferation ◽  
Indoleamine 2,3 Dioxygenase ◽  
And Function

Abstract Abstract 4298 Indoleamine 2,3-dioxygenase (IDO1) and indoleamine 2,3-dioxygenase-like (IDO2) are enzymes involved in the tryptophan catabolism along the kynurenine pathway. While it is established that IDO1-expressing dendritic cells (DCs) contribute to tolerance in a number of biological settings, little is known about the expression and function of IDO2 in DCs. Human DCs can be generated in vitro to obtain immunogenic antigen-presenting cells (APC), used as cellular vaccines. In the clinical setting, DCs are commonly matured with a cytokine cocktail (CC) which includes TNF-a, IL-1b, IL-6 and PGE2. In particular, PGE2 enhances APC function of DCs by increasing IL-12 production and facilitating DC migration to lymph nodes. However, PGE2 is also a strong IDO1 inducer, which by this route can also limit the anti-tumor activity of DC-based immunotherapies. Thus, understanding the roles of IDO1 and IDO2 in DCs may impact the development of vaccines or DC-based immunotherapies. In the present study, we fully characterized IDO1 and IDO2 expression and function in human monocyte-derived dendritic cells (Mo-DCs). Mo-DCs were generated from purified CD14+ monocytes after culture with GM-CSF and IL-4 and then matured with CD40L, LPS alone, LPS plus IFN-g and the CC. We observed that immature Mo-DCs had little if any expression of both IDO1 and IDO2, whereas mature Mo-DCs exhibited upregulation of both enzymes. Among the different maturation stimuli, CC was the most effective in upregulating IDO1 and IDO2, both at the message and protein levels. This effect was associated also with the highest kynurenine production. By means of IDO1 and IDO2 expression, mature Mo-DCs were inhibited in stimulating allogeneic T cell proliferation and generated a population of CD4+CD25+FOXP3+ Tregs which highly suppressed allogeneic and autologous T-cell proliferation. On the basis of evidence that IDO1 is preferentially inhibited by the L-isoform of 1 methyl-tryptophan (1-MT) and IDO2 by the D-isoform, we performed functional enzyme tests in presence of both isoforms. Notably, both isoforms exhibited inhibitory effects, although we observed a stronger effect of L-1-MT than with D-1-MT suggesting a greater contribution of IDO1 than IDO2. These results offer direct evidence that Mo-DCs express functional IDO1 and IDO2 proteins. During the maturation phase, Mo-DCs enhance their tolerogenic qualities, and in particular the capacity to induce Tregs, through the upregulation of both IDO1 and IDO2. Beside the critical role of IDO1 in enhancing the immunosuppressive capacity of DCs, we show, for the first time, that IDO2 is involved also. Our findings imply that, from a clinical standpoint, to improve the efficacy of DC-based vaccines mature DCs should be combined with molecules that can inhibit the activity of both IDO1 and IDO2. Disclosures: Metz: NewLink Genetics: Employment. Prendergast:New Link Genetics Corp: Consultancy, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties.

Sign in / Sign up

Export Citation Format

Share Document