scholarly journals Dendritic cells use macropinocytosis and the mannose receptor to concentrate macromolecules in the major histocompatibility complex class II compartment: downregulation by cytokines and bacterial products.

1995 ◽  
Vol 182 (2) ◽  
pp. 389-400 ◽  
Author(s):  
F Sallusto ◽  
M Cella ◽  
C Danieli ◽  
A Lanzavecchia
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Mononuclear Cells ◽  
Lucifer Yellow ◽  
Human Peripheral Blood ◽  
Mannose Receptor ◽  
Class Ii ◽  
Soluble Antigen ◽  
Gm Csf ◽  
Antigen Capture

We have previously demonstrated that human peripheral blood low density mononuclear cells cultured in granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4 develop into dendritic cells (DCs) that are extremely efficient in presenting soluble antigens to T cells. To identify the mechanisms responsible for efficient antigen capture, we studied the endocytic capacity of DCs using fluorescein isothiocyanate-dextran, horseradish peroxidase, and lucifer yellow. We found that DCs use two distinct mechanisms for antigen capture. The first is a high level of fluid phase uptake via macropinocytosis. In contrast to what has been found with other cell types, macropinocytosis in DCs is constitutive and allows continuous internalization of large volumes of fluid. The second mechanism of capture is mediated via the mannose receptor (MR), which is expressed at high levels on DCs. At low ligand concentrations, the MR can deliver a large number of ligands to the cell in successive rounds. Thus, while macropinocytosis endows DCs with a high capacity, nonsaturable mechanism for capture of any soluble antigen, the MR gives an extra capacity for antigen capture with some degree of selectivity for non-self molecules. In addition to their high endocytic capacity, DCs from GM-CSF + IL-4-dependent cultures are characterized by the presence of a large intracellular compartment that contains high levels of class II molecules, cathepsin D, and lysosomal-associated membrane protein-1, and is rapidly accessible to endocytic markers. We investigated whether the capacity of DCs to capture and process antigen could be modulated by exogenous stimuli. We found that DCs respond to tumor necrosis factor alpha, CD40 ligand, IL-1, and lipopolysaccharide with a coordinate series of changes that include downregulation of macropinocytosis and Fc receptors, disappearance of the class II compartment, and upregulation of adhesion and costimulatory molecules. These changes occur within 1-2 d and are irreversible, since neither pinocytosis nor the class II compartment are recovered when the maturation-inducing stimulus is removed. The specificity of the MR and the capacity to respond to inflammatory stimuli maximize the capacity of DCs to present infectious non-self antigens to T cells.

C-Reactive Protein Binds to FcγRII and Impairs the Differentiation and Function of Dendritic Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1276-1276
Author(s):  
Jianfei Qian ◽  
Jing Yang ◽  
Siqing Wang ◽  
Liang Zhang ◽  
Sungyoul Hong ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Soluble Antigen ◽  
Dependent Manner ◽  
C Reactive Protein ◽  
Reactive Protein ◽  
Tnf Α ◽  
And Function

Abstract Human C-reactive protein (CRP) is an acute-phase protein, and elevated levels of CRP are present in patients with infections, inflammatory diseases, necrosis such as myocardial infarction, or malignancies including multiple myeloma (MM), lymphoma, and carcinoma. CRP has many biological functions and is involved in host defense, regulation of inflammation, and modulation of autoimmune diseases. Although our current understanding of CRP interaction with complement and Fcγ receptors (FcγR) has elucidated a regulatory role of CRP in these disease situations, it is not clear whether CRP affects the function of immune cells such as dendritic cells (DCs). In this study, we investigated the effect of CRP on DC differentiation, maturation, and function. CD14+ monocytes isolated from human peripheral blood mononuclear cells were cultured in RPMI-1640 medium supplemented with GM-CSF and IL-4 for 5 days to generate immature DCs (imDCs), and were further treated with IL-1β and TNF-α for 2 additional days to produce mature DCs (mDCs). CRP (5–100 μg/mL) was added to the cultures during DC differentiation (on days 0 and 3) or maturation (on day 5). The presence of CRP in cultures reduced imDC cell yields in a dose-dependent manner. Significantly lower cell yields were detected in cultures with 5 to 10 μg/mL CRP. Compared with untreated controls, CRP treatment (10 μg/mL) led to inhibited surface expression of DC-related molecules HLA-ABC, CD1a, CD40, and CD54; increased secretion of IL-6, IL-8, and IL-10; reduced production of TGF-β by imDCs; and decreased secretion of IL-12 by mDCs. Furthermore, the function of CRP-treated DCs was also impaired, evident by the markedly decreased ability of imDCs to phagocytose apoptotic cells and to uptake and present soluble antigen to antigen-specific T cells. Compared with untreated controls, CRP-treated mDCs had reduced capacity at activating allospecific T cells, which consequently secreted significantly lower amounts of IFN-γ, IL-2, and TNF-α compared with T cells activated by normal mDCs. Western blot analysis showed that CRP treatment led to inhibited phosphorylation of ERK and p38 MAPKs, and inhibited NFκB activity in the differentiating cells. Monocytes and DCs all express FcγRI (CD64), FcγRII (CD32), and FcγRIII (CD16), and the expression of FcγRII, but not FcγRI and FcγRIII, were upregulated on CRP-treated DCs. The detrimental effects of CRP on DCs were abrogated by blocking antibody against CRP and by antibody against FcγRII, but not against FcγRI or FcγRIII. These results indicate that CRP affected DC differentiation via binding to cell surface FcγRII. Taken together, this study demonstrates for the first time that CRP at high concentrations has detrimental effects on in vitro differentiation and function of DCs. Further studies will be needed to examine the clinical and biological relevance of this observation.

scholarly journals Anti-lymphocyte globulin stimulates normal human T cells to proliferate and to release lymphokines in vitro. A study at the clonal level

Blood ◽  
1988 ◽  
Vol 72 (3) ◽  
pp. 956-963
Author(s):  
GC Barbano ◽  
A Schenone ◽  
S Roncella ◽  
R Ghio ◽  
A Corcione ◽  
...  
Keyword(s):  
T Cells ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Interleukin 2 ◽  
Suppressor Cells ◽  
Peripheral Blood Mononuclear ◽  
Gm Csf ◽  
Recombinant Interleukin 2 ◽  
Macrophage Colony

Abstract Human peripheral blood mononuclear cells (PBMC) were stimulated in vitro with anti-lymphocyte globulin (ALG), and the phenotypic and functional properties of the blasts obtained were investigated. When stained with monoclonal antibodies (MoAbs), all of the blasts were identified as T cells that expressed predominantly the CD4 phenotype (70% of the cells). The remaining blasts were CD8+. These findings demonstrate that ALG stimulates both helper-inducer and cytotoxic- suppressor cells at random since the CD4 to CD8 ratio in the stimulated blasts was the same as in resting PBMC. This ratio is different from that observed in short-term cultures of T cells stimulated with phytohemagglutinin (PHA) under the same conditions (CD4 to CD8 ratio less than 1). ALG-stimulated T cells were cloned by limiting dilution in the presence of recombinant Interleukin-2 (rIL-2). The clones obtained were expanded and maintained in long term cultures with rIL-2. Thirty-two clones were tested for their capacity of producing colony stimulating activity (CSA) or burst promoting activity (BPA). Twenty- eight of them produced CSA and 12 produced BPA. No correlation was found between the surface phenotype and the ability of the clones to produce CSA or BPA (ie, both the CD4+ and CD8+ clones released the cytokines). When 16 of the same clones were tested for II-2 and gamma interferon (gamma IFN) production, 12 were found to be gamma INF and IL- 2 producers. All of the gamma IFN producers also released IL-2, whereas in the single clones no correlation was found with the capacity of releasing BPA and CSA. Supernatants from selected T-cell clones were also tested for hematopoietic growth factor activities in the presence of neutralizing antisera to human granulocyte-macrophage colony stimulating factor (GM-CSF) or to Interleukin-3 (IL-3). It was found that most CSA was attributable to GM-CSF, whereas BPA was mainly related to the presence of IL-3.

Immunopotent Polysaccharides of Different Sources Selectively Activate Human Dendritic Cells.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3873-3873
Author(s):  
Godfrey ChiFung Chan ◽  
W.K. Chan ◽  
H.K. Law ◽  
Z.B. Lin ◽  
Y.L. Lau
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
T Helper ◽  
T Helper 1 ◽  
Xtt Assay ◽  
Peripheral Blood Mononuclear ◽  
Human Dendritic Cells

Abstract Background: Purified polysaccharides extracted from plants and fungi have been shown to induce immune responses in-vivo and vitro over the past decade. Currently, most of these polysaccharides are found to be glucan but with different branch structure and sizes. Their relative potency and effect on human immune cells remains unknown. This study aims to compare their relative effect on human dendritic cell, the most potent antigen presenting cell. Materials & Methods: We selected 2 prototypes of purified polysaccharides extracted from: 1) Ganoderma lucidum (GL, Lingzhi, Reishi) mycelium, a widely used herb with long and branching β (1® 3), (1® 6) glucan structure (provided by Prof. Lin ZB, Beijing) and 2) Barley with shorter and different branching β (1® 3), (1® 4) structure (provided by Prof. Cheung VNK, NY). Their characteristics and chemical properties had been reported previously. Human peripheral blood mononuclear cells (PBMCs) proliferation was studied by XTT assay. Human dendritic cells (DCs) were derived from monocytes and maturation of DCs were determined by: a) immunophenotypic shift using flow cytometer; 2) dextran endocytosis assay and 3) mixed lymphocytes reaction. Cytokine secretions were determined by ELISA test. Comparisons between means were by nonparametric Student’s t test (2-tailed). Results: We found that purified polysaccharides from GL but not barley could induce PBMCs proliferation and maturation of DCs. GL polysaccharides could enhance phenotypic and functional maturation of DCs with significant IL-12 and IL-10 production. DCs were relatively inert to Barley glucans stimulation. However, both polysaccharides did not polarize T cells into the direction of T helper 1, T helper 2 or regulatory T cells. Conclusions: Our study shown that purified polysaccharides extracted from plants and fungi have different effect on human DCs and their potency and effects are probably affected by their respective sources and structures.

Dendritic cells derived from patients with multiple sclerosis show high CD1a and low CD86 expression

2001 ◽  
Vol 7 (2) ◽  
pp. 95-99 ◽  
Author(s):  
Yu-Min Huang ◽  
Mathilde Kouwenhoven ◽  
Ya-Ping Jin ◽  
Rayomand Press ◽  
Wen-Xin Huang ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
T Cells ◽  
Dendritic Cells ◽  
Mononuclear Cells ◽  
Neurological Diseases ◽  
Interleukin 4 ◽  
Gm Csf ◽  
The Central Nervous System ◽  
Macrophage Colony ◽  
Antigen Presenting

Dendritic cells (DC) are important antigen presenting cells (APC) and play a major role in initiating and orchestrating immune responses by priming T cells. Little is known about involvement of DC in multiple sclerosis (MS), where auto-aggressive T cells against myelin autoantigens are considered to contribute to inflammation and demyelination in the central nervous system. In this study, we compared phenotype and cytokine secretion of DC from patients with MS, other neurological diseases (OND) and healthy subjects. DC were generated from blood adherent mononuclear cells (MNC) by culture for 7 days with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). The yield and morphology of DC were similar in MS patients and controls. In both, the DC phenotype was that of immature myeloid lineage, comprising CD1a+ and CD11c+. The proportion of CD1a+ DC, being important for presentation of lipid antigens to T cells, was higher in MS patients compared to controls. The proportion of CD86+ DC, a co-stimulatory molecule that is assumed to promote Th2 differentiation, was low in MS. Low proportions of CD86+ DC were only observed in untreated MS patients but not in patients treated with IFN-b. Production of IL-10 and IL-12 p40 by DC did not differ in MS patients and controls. These findings indicate that alterations of functionally important surface molecules on DC are associated with MS.

Activated Dendritic Cells From Bone Marrow Cells of Mice Receiving Cytokine-Expressing Tumor Cells Are Associated With the Enhanced Survival of Mice Bearing Syngeneic Tumors

Blood ◽  
1999 ◽  
Vol 93 (12) ◽  
pp. 4328-4335
Author(s):  
Shin-ichiro Fujii ◽  
Hirofumi Hamada ◽  
Koji Fujimoto ◽  
Taizo Shimomura ◽  
Makoto Kawakita
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Dendritic Cells ◽  
Tumor Cells ◽  
Mononuclear Cells ◽  
Bone Marrow Cells ◽  
Interleukin 4 ◽  
Gm Csf ◽  
Tumor Bearing ◽  
Macrophage Colony

Dendritic cells (DCs), which phagocytose antigens and subsequently proliferate and migrate, may be the most powerful antigen-presenting cells that activate naive T cells. To determine their role in the immune response to tumors, we used WEHI-3B murine leukemia cells transduced with adenovirus vectors expressing cytokines. We found that mixtures of irradiated cells expressing granulocyte-macrophage colony-stimulating factor (GM-CSF) plus those expressing interleukin-4 (IL-4) or tumor necrosis factor  (TNF) protected mice against WEHI-3B–induced leukemias. When bone marrow mononuclear cells (BMMNCs) obtained from mice that had been injected with irradiated, cytokine-expressing tumor cells were injected into tumor-bearing mice, the survival of the latter was significantly prolonged; the longest survival was observed in mice receiving BMMNCs containing an increased number of DCs from animals injected with a mixture of tumor cells expressing GM-CSF with those expressing IL-4. Assay for antileukemic effects in spleen of the latter animals showed specific antitumor cytotoxicity against WEHI-3B, suggesting that DCs from donor mice activate specific T cells in the tumor-bearing recipients. These results suggest that the infusion of syngeneic BMMNCs stimulated with cytokine-expressing tumor cells may be effective in treating certain types of tumors.

scholarly journals Dramatic increase in the numbers of functionally mature dendritic cells in Flt3 ligand-treated mice: multiple dendritic cell subpopulations identified.

1996 ◽  
Vol 184 (5) ◽  
pp. 1953-1962 ◽  
Author(s):  
E Maraskovsky ◽  
K Brasel ◽  
M Teepe ◽  
E R Roux ◽  
S D Lyman ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Class Ii ◽  
Terminal State ◽  
T Cell Response ◽  
Daily Injection ◽  
Flt3 Ligand ◽  
Cd11b Expression ◽  
Gm Csf

Dendritic cells (DC) are the most efficient APC for T cells. The clinical use of DC as vectors for anti-tumor and infectious disease immunotherapy has been limited by their trace levels and accessibility in normal tissue and terminal state of differentiation. In the present study, daily injection of human Flt3 ligand (Flt3L) into mice results in a dramatic numerical increase in cells co-expressing the characteristic DC markers-class II MHC, CD11c, DEC205, and CD86. In contrast, in mice treated with either GM-CSF, GM-CSF plus IL-4, c-kit ligand (c-kitL), or G-CSF, class II+ CD11c+ cells were not significantly increased. Five distinct DC subpopulations were identified in the spleen of Flt3L-treated mice using CD8 alpha and CD11b expression. These cells exhibited veiled and dendritic processes and were as efficient as rare, mature DC isolated from the spleens of untreated mice at presenting allo-Ag or soluble Ag to T cells, or in priming an Ag-specific T cell response in vivo. Dramatic numerical increases in DC were detected in the bone marrow, gastro-intestinal lymphoid tissue (GALT), liver, lymph nodes, lung, peripheral blood, peritoneal cavity, spleen, and thymus. These results suggest that Flt3L could be used to expand the numbers of functionally mature DC in vivo for use in clinical immunotherapy.

scholarly journals Immortalized dendritic cell line fully competent in antigen presentation initiates primary T cell responses in vivo.

1993 ◽  
Vol 178 (6) ◽  
pp. 1893-1901 ◽  
Author(s):  
P Paglia ◽  
G Girolomoni ◽  
F Robbiati ◽  
F Granucci ◽  
P Ricciardi-Castagnoli
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Dendritic Cell ◽  
Cell Line ◽  
Mhc Class Ii ◽  
Class Ii ◽  
Gm Csf ◽  
Antigen Presenting

Dendritic cells (DC) can provide all the known costimulatory signals required for activation of unprimed T cells and are the most efficient and perhaps the critical antigen presenting cells in the induction of primary T cell-mediated immune responses. It is now shown that mouse cell lines with many of the features of DC can be generated using the MIB phi 2-N11 retroviral vector transducing a novel envAKR-mycMH2 fusion gene. The immortalized dendritic cell line (CB1) displays most of the morphologic, immunophenotypic, and functional attributes of DC, including constitutive expression of major histocompatibility complex (MHC) class II molecules, costimulatory molecules B7/BB1, heat stable antigen, intracellular adhesion molecule 1, and efficient antigen-presenting ability. Granulocyte/macrophage colony-stimulating factor (GM-CSF) proved to be effective in increasing MHC class II molecule expression and in enhancing presentation of native protein antigens. In comparison with macrophages, CB1 dendritic cells did not exhibit phagocytic and chemotactic activity in response to various stimuli and lipopolysaccharide activation was ineffective in inducing tumor necrosis factor alpha or interleukin 1 beta production. CB1 cells, pulsed with haptens in vitro and injected into naive mice were able to induce delayed-type hypersensitivity responses, further increased with pretreatment with GM-CSF, indicating that these cells may represent an immature, rather than a mature DC. The ability of CB1 to prime T cells in vivo could provide a tool to design novel immunization strategies.

scholarly journals Uptake of HLA Alloantigens via CD89 and CD206 Does Not Enhance Antigen Presentation by Indirect Allorecognition

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Eytan Breman ◽  
Jurjen M. Ruben ◽  
Kees L. Franken ◽  
Mirjam H. M. Heemskerk ◽  
Dave L. Roelen ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Antigen Presentation ◽  
Antigen Presenting Cells ◽  
Mannose Receptor ◽  
Class Ii ◽  
Hla Class Ii ◽  
Indirect Allorecognition ◽  
Antigen Presenting

In organ transplantation, alloantigens are taken up by antigen presenting cells and presented via the indirect pathway to T-cells which in turn can induce allograft rejection. Monitoring of these T-cells is of major importance; however no reliable assay is available to routinely monitor indirect allorecognition. Recently we showed that HLA monomers can be successfully used to monitor indirect allorecognition. Targeting antigens to endocytic receptors on antigen presenting cells may further enhance the presentation of antigens via HLA class II and improve the efficiency of this assay. In the current study we explored targeting of HLA monomers to either CD89 expressing monocytes or mannose receptor expressing dendritic cells. Monomer-antibody complexes were generated using biotin-labeled monomers and avidin labeling of the antibodies. We demonstrate that targeting the complexes to these receptors resulted in a dose-dependent HLA class II mediated presentation to a T-cell clone. The immune-complexes were efficiently taken up and presented to T-cells. However, the level of T-cell reactivity was similar to that when only exogenous antigen was added. We conclude that HLA-A2 monomers targeted for presentation through CD89 on monocytes or mannose receptor on dendritic cells lead to proper antigen presentation but do not enhance indirect allorecognition via HLA-DR.

scholarly journals Cas9-derived peptides presented by MHC Class II that elicit proliferation of CD4+ T-cells

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Vijaya L. Simhadri ◽  
Louis Hopkins ◽  
Joseph R. McGill ◽  
Brian R. Duke ◽  
Swati Mukherjee ◽  
...  
Keyword(s):  
T Cells ◽  
Mhc Class Ii ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Class Ii ◽  
Data Sets ◽  
Peripheral Blood Mononuclear ◽  
Mhc Ii ◽  
The North ◽  
Entire Sequence

AbstractCRISPR–Cas9 mediated genome editing offers unprecedented opportunities for treating human diseases. There are several reports that demonstrate pre-existing immune responses to Cas9 which may have implications for clinical development of CRISPR-Cas9 mediated gene therapy. Here we use 209 overlapping peptides that span the entire sequence of Staphylococcus aureus Cas9 (SaCas9) and human peripheral blood mononuclear cells (PBMCs) from a cohort of donors with a distribution of Major Histocompatibility Complex (MHC) alleles comparable to that in the North American (NA) population to identify the immunodominant regions of the SaCas9 protein. We also use an MHC Associated Peptide Proteomics (MAPPs) assay to identify SaCas9 peptides presented by MHC Class II (MHC-II) proteins on dendritic cells. Using these two data sets we identify 22 SaCas9 peptides that are both presented by MHC-II proteins and stimulate CD4+ T-cells.

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