scholarly journals Pneumococcal Polysaccharides Interact with Human Dendritic Cells

2006 ◽  
Vol 74 (3) ◽  
pp. 1890-1895 ◽  
Author(s):  
Ulrike Meltzer ◽  
David Goldblatt
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Fluorescein Isothiocyanate ◽  
Human Monocyte ◽  
Interleukin 12 ◽  
Blood Monocytes ◽  
Kinase Activation ◽  
Cytokine Balance ◽  
Human Dendritic Cells

ABSTRACT Dendritic cells (DCs) are critical antigen presentation cells whose influence on murine immune responses to polysaccharide antigens has only recently been elucidated. Little is known about human DC-polysaccharide interactions. We set out to study the interaction between human monocyte-derived DCs and pneumococcal capsular polysaccharides (PPS) in vitro. Immature DCs were generated from peripheral blood monocytes and incubated with fluorescein isothiocyanate-labeled PPS type 9N or 14 for assessment of uptake. DCs were exposed to PPS type 1, 6B, 9N, 14, 19F, or 23F in the absence or presence of Escherichia coli lipopolysaccharide (LPS) for assessment of phenotypic DC maturation and cytokine production. PPS were taken up by immature DCs and proceeded to HLA-DR+ and lysosome-associated membrane protein-1+ late endosomal compartments. Uptake was reduced in the presence of cytochalasin D and wortmannin, suggesting that both cytoskeletal rearrangements and phosphatidylinositol 3-kinase activation may be required for internalization. None of the PPS tested induced DC phenotype changes, maturation, or interleukin-12 (IL-12)/IL-10 production. However, PPS were capable of modulating the response of the DCs to a second signal such as LPS. Exposure of DCs to PPS in the presence of LPS resulted in an altered cytokine balance with significantly increased IL-10 production and reduced IL-12 production compared to LPS alone. This effect was not seen using the control antigen tetanus toxoid. DC-pneumococcus interaction may affect subsequent immune responses to pneumococci, as an altered cytokine balance may have a profound effect on DC-driven T-cell priming.

scholarly journals IN LABORATORY GENERATION AND MATURATION OF HUMAN MONOCYTE-DERIVED DENDRITIC CELLS FOR CANCER IMMUNOTHERAPY

2020 ◽  
pp. 46-52
Author(s):  
KANCHAN K. MISHRA ◽  
SUMIT BHARADVA ◽  
MEGHNAD G. JOSHI ◽  
ARVIND GULBAKE
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Gradient Centrifugation ◽  
Critical Role ◽  
Human Monocyte ◽  
Blood Monocytes ◽  
Adaptive Immune ◽  
Immunodeficiency Virus ◽  
Adaptive Immune Systems

Dendritic cells (DCs) play a critical role in the regulation of adaptive immune responses, furthermore they act as a bridge between the innate and the adaptive immune systems they have been ideal candidates for cell-based immunotherapy of cancers and infections in humans. The first reported trial using DCs in 1995, since they have been used in trials all over the world for several of indications, including cancer and human immunodeficiency virus infection. Generally, for in vitro experiments or for DCs vaccination monocyte-derived dendritic cells (moDCs) were generated from purified monocytes that isolated from peripheral blood by density gradient centrifugation. A variety of methods can be used for enrichment of monocytes for generation of clinical-grade DCs. Herein we summarized up to date understanding of systems and inputs used in procedures to differentiate DCs from blood monocytes in vitro.

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 CRISPR-based functional genomics in human dendritic cells

2020 ◽  
Author(s):  
Marco Jost ◽  
Amy N. Jacobson ◽  
Jeffrey A. Hussmann ◽  
Giana Cirolia ◽  
Michael A. Fischbach ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Genome Editing ◽  
Individual Variation ◽  
Human Microbiome ◽  
Human Monocyte ◽  
Genetic Screens ◽  
Mucosal Surfaces ◽  
Immune Phenotypes ◽  
Human Dendritic Cells

AbstractDendritic cells (DCs) regulate processes ranging from antitumor and antiviral immunity to host-microbe communication at mucosal surfaces. It remains difficult, however, to genetically manipulate human DCs, limiting our ability to probe how DCs elicit specific immune responses. Here, we develop a CRISPR/Cas9 genome editing method for human monocyte-derived DCs (moDCs) that mediates knockouts with a median efficiency of >93% across >300 genes. Using this method, we perform genetic screens in moDCs, identifying mechanisms by which DCs tune responses to lipopolysaccharides from the human microbiome. In addition, we reveal donor-specific responses to lipopolysaccharides, underscoring the importance of assessing immune phenotypes in donor-derived cells, and identify genes that control this specificity, highlighting the potential of our method to pinpoint determinants of inter-individual variation in immune responses. Our work sets the stage for a systematic dissection of the immune signaling at the host-microbiome interface and for targeted engineering of DCs for neoantigen vaccination.

scholarly journals Infection of Human Dendritic Cells with a Mycobacterium tuberculosis sigE Mutant Stimulates Production of High Levels of Interleukin-10 but Low Levels of CXCL10: Impact on the T-Cell Response

2006 ◽  
Vol 74 (6) ◽  
pp. 3296-3304 ◽  
Author(s):  
Elena Giacomini ◽  
Ambar Sotolongo ◽  
Elisabetta Iona ◽  
Martina Severa ◽  
Maria Elena Remoli ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Mycobacterium Tuberculosis ◽  
Human Monocyte ◽  
Interleukin 10 ◽  
T Cell Response ◽  
Interleukin 12 ◽  
Necrosis Factor Alpha ◽  
Effector Cells ◽  
Human Dendritic Cells

ABSTRACT The Mycobacterium tuberculosis genome encodes 13 sigma factors. We have previously shown that mutations in some of these transcriptional activators render M. tuberculosis sensitive to various environmental stresses and can attenuate the virulence phenotype. In this work, we focused on extracytoplasmic factor σE and studied the effects induced by the deletion of its structural gene (sigE) in the infection of human monocyte-derived dendritic cells (MDDC). We found that the wild-type M. tuberculosis strain (H37Rv), the sigE mutant (ST28), and the complemented strain (ST29) were able to infect dendritic cells (DC) to similar extents, although at 4 days postinfection a reduced ability to grow inside MDDC was observed for the sigE mutant ST28. After mycobacterium capture, the majority of MDDC underwent full maturation and expressed both inflammatory cytokines, such as tumor necrosis factor alpha, and the regulatory cytokines interleukin-12 (IL-12), IL-18, and beta interferon (IFN-β). Conversely, a higher level of production of IL-10 was observed in ST28-infected MDDC compared to H37Rv- or ST29-infected cell results. However, in spite of the presence of IL-10, supernatants from ST28-infected DC induced IFN-γ production by T cells similarly to those from H37Rv-infected DC culture. On the other hand, IL-10 impaired CXCL10 production in sigE mutant-infected DC and, indeed, its neutralization restored CXCL10 secretion. In line with these results, supernatants from ST28-infected cells showed a decreased capability to recruit CXCR3+ CD4+ T cells compared to those obtained from H37Rv-infected DC culture. Thus, our findings suggest that the sigE mutant-induced secretion of IL-10 inhibits CXCL10 expression and, in turn, the recruitment of activated-effector cells involved in the formation of granulomas.

Expression of Surface Antigens During the Differentiation of Human Dendritic Cells vs Macrophages from Blood Monocytes in vitro

Immunobiology ◽  
1999 ◽  
Vol 200 (2) ◽  
pp. 187-204 ◽  
Author(s):  
Alessandro D. Santin ◽  
Paul L. Hermonat ◽  
Maurizio Chiriva-Internat Ravaggi ◽  
Maurizio Chiriva-Internat ◽  
Martin J. Cannon ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Surface Antigens ◽  
Blood Monocytes ◽  
Human Dendritic Cells

Chronic and Acute Alcohol Exposure Prevents Monocyte-Derived Dendritic Cells from Differentiating and Maturing

2008 ◽  
Vol 21 (4) ◽  
pp. 929-939 ◽  
Author(s):  
B. Buttari ◽  
E. Profumo ◽  
R. Mancinelli ◽  
U. Cesta Incani ◽  
M.E. Tosti ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Healthy Subjects ◽  
Alcohol Exposure ◽  
Hla Dr ◽  
Maturation In Vitro ◽  
Tnf Α ◽  
Human Dendritic Cells ◽  
And Control

Increasing evidence suggests that alcohol abuse may be linked to adverse immunomodulatory effects on immune responses. Our study was undertaken to clarify the immunological consequences of chronic and acute alcohol exposure on differentiation and maturation of human dendritic cells (DCs). Using immunochemical and cytofluorimetric analysis we determined the phenotype and functions of monocyte-derived DCs from alcoholics and healthy subjects and analyzed their ability to respond to lipopolysaccharide (LPS) in the presence or absence of ethanol (EtOH) exposure. Our results showed that alcoholics' monocytes differentiated to immature DCs with altered phenotype and functions (alc-iDCs). Alc-iDCs showed fewer CD1a+ cells, weaker CD86 expression and higher HLA-DR expression associated with lower endocytosis and allostimulatory functions than iDCs from healthy subjects (control-iDCs). Despite these impairments, alc-iDCs produced TNF-α and IL-6 in large amounts. LPS stimulation failed to induce full phenotypical and functional alc-iDC maturation. In vitro acute EtOH exposure also prevented alc-iDCs and control-iDCs from maturing in response to LPS. T-cell priming experiments showed that EtOH treatment prevented LPS-stimulated control-iDCs from priming and polarizing naïve allogeneic T cells into Th1 cells, thus favouring a predominant Th2 environment. Collectively, our results provide evidence that chronic and acute alcohol exposure prevents DCs from differentiating and maturing in response to a microbial stimulus.

A subset of human monocyte-derived dendritic cells expresses high levels of interleukin-12 in response to combined CD40 ligand and interferon-γ treatment

Blood ◽  
2000 ◽  
Vol 96 (10) ◽  
pp. 3499-3504 ◽  
Author(s):  
Paul J. Mosca ◽  
Amy C. Hobeika ◽  
Timothy M. Clay ◽  
Smita K. Nair ◽  
Elaine K. Thomas ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Human Monocyte ◽  
Cd40 Ligand ◽  
Cell Surface Expression ◽  
Interleukin 12 ◽  
Cytokine Detection

Abstract Dendritic cells (DCs) may arise from multiple lineages and progress through a series of intermediate stages until fully mature, at which time they are capable of optimal antigen presentation and T-cell activation. High cell surface expression of CD83 is presumed to correlate with full maturation of DCs, and a number of agents have been shown to increase CD83 expression on DCs. We hypothesized that interleukin 12 (IL-12) expression would be a more accurate marker of functionally mature DCs capable of activating antigen-specific T cells. We used combinations of signaling through CD40, using CD40 ligand trimer (CD40L), and interferon gamma to demonstrate that CD83 expression is necessary but not sufficient for optimal production of IL-12 by DCs. Phenotypically mature DCs could be induced to produce high levels of IL-12 p70 only when provided 2 simultaneous stimulatory signals. By intracellular cytokine detection, we determined that only a subset of cells that express high levels of CD80 and CD83 generate large amounts of IL-12. DCs matured with both signals are superior to DCs stimulated with the individual agents in activating antigen-specific T cell in vitro. These findings have important implications regarding the identification, characterization, and clinical application of functionally mature DCs.

Enhancing the immunostimulatory function of dendritic cells by transfection with mRNA encoding OX40 ligand

Blood ◽  
2005 ◽  
Vol 105 (8) ◽  
pp. 3206-3213 ◽  
Author(s):  
Jens Dannull ◽  
Smita Nair ◽  
Zhen Su ◽  
David Boczkowski ◽  
Christian DeBeck ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
T Cell Responses ◽  
Human Monocyte ◽  
Interleukin 12 ◽  
T Helper ◽  
Cell Responses ◽  
Mrna Transfection

Abstract The objective of this study was to investigate whether the immunostimulatory properties of human monocyte-derived dendritic cells (DCs) could be enhanced by triggering OX40/OX40L signaling. Since monocyte-derived DCs possess only low-cell surface levels of OX40L in the absence of CD40 signaling, OX40L was expressed by transfection of DCs with the corresponding mRNA. We show that OX40L mRNA transfection effectively enhanced the immunostimulatory function of DCs at multiple levels: OX40L mRNA transfection augmented allogeneic and HLA class II epitope-specific CD4+ T-cell responses, improved the stimulation of antigen-specific cytotoxic T lymphocytes (CTLs) in vitro without interfering with the prostaglandin E2 (PGE2)–mediated migratory function of the DCs, and facilitated interleukin 12 p70 (IL-12p70)–independent T helper type 1 (Th1) polarization of naive CD4+ T-helper cells. Furthermore, vaccination of tumor-bearing mice using OX40L mRNA–cotransfected DCs resulted in significant enhancement of therapeutic antitumor immunity due to in vivo priming of Th1-type T-cell responses. Our data suggest that transfection of DCs with OX40L mRNA may represent a promising strategy that could be applied in clinical immunotherapy protocols, while circumventing the current unavailability of reagents facilitating OX40 ligation.

scholarly journals Stimulation of Dendritic Cells via CD40 Enhances Immune Responses to Mycobacterium tuberculosisInfection

2001 ◽  
Vol 69 (4) ◽  
pp. 2456-2461 ◽  
Author(s):  
Caroline Demangel ◽  
Umaimainthan Palendira ◽  
Carl G. Feng ◽  
Andrew W. Heath ◽  
Andrew G. D. Bean ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Immune Responses ◽  
Protective Efficacy ◽  
Interleukin 12 ◽  
Ifn Γ ◽  
Cellular Immune ◽  
Stimulation Of

ABSTRACT The resolution of pulmonary tuberculosis (TB) critically depends on the development of the Th1 type of immune responses, as exemplified by the exacerbation of TB in IL-12-deficient mice. Therefore, vaccination strategies optimizing IL-12 production by antigen-presenting cells (APC) in response to mycobacteria may have enhanced protective efficacy. Since dendritic cells (DC) are the critical APC for activation of CD4+ and CD8+ T cells, we examined whether stimulation of Mycobacterium bovis bacillus Calmette Guérin (BCG)-infected DC via CD40 increased their ability to generate Th1-oriented cellular immune responses. Incubation of DC with an agonistic anti-CD40 antibody activated CD40 signaling in DC, as shown by increased expression of major histocompatibility complex class II and costimulatory molecules, mRNA production for proinflammatory cytokines and interleukin 12 (IL-12) p40. This activation pattern was maintained when DC were stimulated with anti-CD40 antibody and infected with BCG. Importantly, CD40-stimulated BCG-infected DC displayed increased capacity to release bioactive IL-12 and to activate gamma interferon (IFN-γ) producing T cells in vitro. Moreover, when C57BL/6 mice were immunized with these DC and challenged with aerosol Mycobacterium tuberculosis, increased levels of mRNA for IL-12 p40, IL-18, and IFN-γ were present in the draining mediastinal lymph nodes. However, the mycobacterial burden in the lungs was not reduced compared to that in mice immunized with BCG-infected non-CD40-stimulated DC. Therefore, although the manipulation of DC via CD40 is effective for enhancing immune responses to mycobacteria in vivo, additional strategies are required to increase protection against virulent M. tuberculosis infection.

Serial Analysis of Gene Expression in Human Monocyte-Derived Dendritic Cells

Blood ◽  
1999 ◽  
Vol 94 (3) ◽  
pp. 845-852 ◽  
Author(s):  
Shin-ichi Hashimoto ◽  
Takuji Suzuki ◽  
Hong-Yan Dong ◽  
Shigenori Nagai ◽  
Nobuyuki Yamazaki ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dendritic Cells ◽  
Cell Structure ◽  
Human Monocyte ◽  
Interleukin 4 ◽  
Maturation Stage ◽  
Blood Monocytes ◽  
Gm Csf ◽  
Highly Expressed Genes

Dendritic cells (DCs) are professional antigen-presenting cells in the immune system and can be generated in vitro from hematopoietic progenitor cells in the bone marrow, CD34+ cord blood cells, precursor cells in the peripheral blood, and blood monocytes by culturing with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-4, and tumor necrosis factor-. We have performed serial analysis of gene expression (SAGE) in DCs derived from human blood monocytes. A total of 58,540 tag sequences from a DC complementary DNA (cDNA) library represented more than 17,000 different genes, and these data were compared with SAGE analysis of tags from monocytes (Mo) and GM-CSF–induced macrophages (M◊). Many of the genes that were differentially expressed in DCs were identified as genes encoding proteins related to cell structure and cell motility. Interestingly, the highly expressed genes in DCs encode chemokines such as TARC, MDC, and MCP-4, which preferentially chemoattract Th2-type lymphocytes. Although DCs have been considered to be very heterogeneous, the identification of specific genes expressed in human Mo-derived DCs should provide candidate genes to define subsets of, the function of, and the maturation stage of DCs and possibly also to diagnose diseases in which DCs play a significant role, such as autoimmune diseases and neoplasms. This study represents the first extensive gene expression analysis in any type of DCs.

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