Dendritic cells (DCs) are important immune cells linking innate and adaptive immune responses. DCs encounter various self and non-self antigens present in the environment and induce different types of antigen specific adaptive immune responses. DCs can be classified into lymphoid tissue-resident DCs, migratory DCs, non-lymphoid resident DCs, and monocyte derived DCs (moDCs). Recent work has also established that DCs consist of developmentally and functionally distinct subsets that differentially regulate T lymphocyte function. The development of different DC subsets has been found to be regulated by a network of different cytokines and transcriptional factors. Moreover, the response of DC is tightly regulated to maintain the homeostasis of immune system. MicroRNAs (miRNAs) are an important class of cellular regulators that modulate gene expression and thereby influence cell fate and function. In the immune system, miRNAs act at checkpoints during hematopoietic development and cell subset differentiation, they modulate effector cell function, and are implicated in the maintenance of homeostasis. DCs are also regulated by miRNAs. In the past decade, much progress has been made to understand the role of miRNAs in regulating the development and function of DCs. In this review, we summarize the origin and distribution of different mouse DC subsets in both lymphoid and non-lymphoid tissues. The DC subsets identified in human are also described. Recent progress on the function of miRNAs in the development and activation of DCs and their functional relevance to autoimmune diseases are discussed.
Animals ; Autoimmune Diseases ; immunology ; Cell Differentiation ; immunology ; Dendritic Cells ; cytology ; immunology ; Humans ; MicroRNAs ; immunology ; Monocytes ; cytology ; immunology ; T-Lymphocytes ; cytology ; immunology

OBJECTIVETo investigate the mechanisms underlying the ability ofheparin-treated dendritic cells (DCs) to promote Th0 to Th1 differentiation in chronic hepatitis B (CHB).

METHODSPeripheral blood mononuclear cells (PBMCs) were isolated from CHB patients and cultured in RPMI-1640 with recombinant GM-CSF and IL-4 with or without heparin to obtain DCs for study. The levels of Toll-like receptors (TLRs) on the DCs were measured using FACS and qPCR techniques.DC subsets with high expression of TLRs were selected for analysis of functional changes by treatment with the corresponding TLR-siRNA. The CD4+ T cell subpopulation was purified from peripheral blood by Dynal immunomagnetic beads, and then the production of IL-12 by DCs in the presence of poly(I:C) or R848 and ofIFN and IL-4 by Th cells co-cultured with DCs was evaluated by ELISA. The t-test was used for statistical analysis.

RESULTSTLR3 expression, and not expression of TLR 7 or TLR8,was significantly increased in heparin-treated DCs as compared to levels detected in the DCs without heparin treatment (t =2.849,P less than 0.05;t =3.027,P less than 0.05). The level of IL-12 produced by heparin-treated DCs stimulated with poly(I:C) was obviously higher than that produced by DCs without heparin treatment and stimulated with poly(I: C) (t =8.68,P less than 0.01) or with R848 (t =19.01,P less than 0.01). However, the IL-12 production by TLR3-siRNA transfected-DCs was significantly reduced (t =31.49, P less than 0.01).When Th cells from allogenic patients with CHB were co-cultured with the TLR3-siRNA transfectedDCs, the frequency ofCD4+ IFN+ cells was significantly reduced (1.64+/-0.57% vs.6.31+/-0.88%,P less than 0.01),as was the capability of Thl to generate IFNg (t =20.83,Pless than 0.01).

CONCLUSIONHeparin may have up-regulated the TLR3 expression level of DCs, and sequentially promoted Th0 to Th1 differentiation.

CD4-Positive T-Lymphocytes ; cytology ; Cell Differentiation ; Coculture Techniques ; Dendritic Cells ; cytology ; Granulocyte-Macrophage Colony-Stimulating Factor ; pharmacology ; Heparin ; pharmacology ; Hepatitis B, Chronic ; immunology ; Humans ; Interferon-gamma ; metabolism ; Interleukin-12 ; metabolism ; Interleukin-4 ; pharmacology ; Monocytes ; cytology ; Recombinant Proteins ; pharmacology ; Toll-Like Receptor 3 ; metabolism

The efficiency of dendritic cell-activated and cytokine-induced killer cell (DC-CIK) therapy on children with acute myeloid leukemia (AML) after chemotherapy was investigated. Mononuclear cells were collected from children achieving complete remission after chemotherapy, cultured in vitro and transfused back into the same patient. Interleukin-2 (IL-2) was injected subcutaneously every other day 10 times at the dose of 1 × 10(6) units. Peripheral blood lymphocyte subsets and minimal residual disease (MRD) were detected by flow cytometry. Function of bone marrow was monitored by methods of morphology, immunology, cytogenetics and molecular biology. The side effects were also observed during the treatment. The average follow-up period for all the 22 patients was 71 months and relapse occurred in two AML patients (9.1%). The percentage of CD3(+)/CD8(+) cells in peripheral blood of 15 patients at the 3rd month after DC-CIK treatment (36.73% ± 12.51%) was dramatically higher than that before treatment (29.20% ± 8.34%, P < 0.05). The MRD rate was >0.1% in 5 patients before the treatment, and became lower than 0.1% 3 months after the treatment. During the transfusion of DC-CIK, side effects including fever, chills and hives appeared in 7 out of 22 (31.82%) cases but disappeared quickly after symptomatic treatments. There were no changes in electrocardiography and liver-renal functions after the treatment. MRD in children with AML can be eliminated by DC-CIK therapy which is safe and has fewer side effects.
Adolescent ; Antineoplastic Agents ; therapeutic use ; Bone Marrow ; drug effects ; immunology ; pathology ; Child ; Child, Preschool ; Cytokine-Induced Killer Cells ; cytology ; immunology ; transplantation ; Dendritic Cells ; cytology ; immunology ; transplantation ; Female ; Humans ; Immunotherapy, Adoptive ; methods ; Injections, Subcutaneous ; Interleukin-2 ; therapeutic use ; Leukemia, Myeloid, Acute ; immunology ; pathology ; therapy ; Male ; Neoplasm, Residual ; Primary Cell Culture ; Recurrence ; Remission Induction ; Treatment Outcome

Kidney dendritic cells(DC) play important roles in the pathogenesis of kidney diseases. Kidney DC presents anti-inflammatory effects in certain kidney diseases, sometimes presents pro-inflammation in other diseases, and sometimes their effects are changing in different stages of the disease, suggesting that the differentiation and function of kidney DC may be influenced by microenvironment. This article reviews the origin and distribution of kidney DC subsets and their roles in the pathogenesis of kidney diseases such as lupus nephritis and pyelonephritis, and the functional regulation of kidney DC by proximal tubule epithelial cells.
Cell Differentiation ; Dendritic Cells ; cytology ; immunology ; Epithelial Cells ; cytology ; Humans ; Inflammation ; immunology ; Kidney ; cytology ; Kidney Diseases ; immunology ; Lupus Nephritis ; immunology ; Pyelonephritis ; immunology

Dendritic cells (DCs) are key modulators that shape the immune system. In mucosal tissues, DCs act as surveillance systems to sense infection and also function as professional antigen-presenting cells that stimulate the differentiation of naive T and B cells. On the basis of their molecular expression, DCs can be divided into several subsets with unique functions. In this review, we focus on intestinal DC subsets and their function in bridging the innate signaling and adaptive immune systems to maintain the homeostasis of the intestinal immune environment. We also review the current strategies for manipulating mucosal DCs for the development of efficient mucosal vaccines to protect against infectious diseases.
Animals ; Dendritic Cells/*immunology/metabolism ; Humans ; Immunity, Mucosal ; Intestinal Mucosa/cytology/*immunology ; T-Lymphocytes, Helper-Inducer/immunology

OBJECTIVETo explore the in vitro anti-tumor effect and mechanism of dendritic cell (DC) tumor vaccine induced by astragalus polysacharin (APS).

METHODSPeripheral blood mononuclear cells (PBMCs) isolated from human peripheral blood. DCs obtained from human peripheral blood were cultivated and added with culture solution for in vitro inducing them to immature DCs. On the 5th day of culture, 100 microg/mL (as the final concentration) APS was added to cells in the APS group. DCs were induced to mature in the cytokine groups by adding 20 ng/mL rhTNF-alpha (as the final concentration). Changes of morphology and phenotype of DCs were observed. Mature DCs were sensitized with tumor antigen SGC-7901 and co-cultured with allogeneic T cells. The proliferative function of T lymphocytes was detected by MTT assay. Levels of IL-12 and IFN-gamma in co-cultured supernatant were detected by ELISA. Cytotoxic lymphocytes (CTL) activated by DC were co-cultured with tumor cell SGC-7901. The specific killing capacity of CTL to target cells was detected by LDH release assay.

RESULTSThe morphological observation and phenotypic identification of APS induced DCs were in accordance with the characteristics of mature DCs. APS induced mature DCs could stimulate the proliferation of allogeneic T lymphocytes. The proliferation index of T cells increased with increased ratio of stimulator cells to effector cells (P < 0.05). Levels of IL-12 and IFN-gamma in co-culture supernatant significantly increased in a time-dependent manner (P < 0.05). CTL cells activated by sensitization of DCs could significantly kill tumor cells, and the killing effect increased along with increased effector-to-target ratio.

CONCLUSIONAPS could in vitro induce DCs to mature, promote its antigen-presenting capacity, effectively activate CTLs, and enhance anti-tumor function of the organism.

Antigen-Presenting Cells ; cytology ; drug effects ; immunology ; Cancer Vaccines ; immunology ; Cell Line ; Cell Proliferation ; drug effects ; Coculture Techniques ; Dendritic Cells ; cytology ; drug effects ; immunology ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Interferon-gamma ; immunology ; Interleukin-12 ; immunology ; Leukocytes, Mononuclear ; cytology ; immunology ; Lymphocyte Activation ; T-Lymphocytes, Cytotoxic ; cytology ; drug effects

OBJECTIVETo observe the anti-virus effects of andrographolide (AD) on the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) signaling pathway when immunological cells were infected with H1N1.

METHODSLeukomonocyte was obtained from umbilical cord blood by Ficoll density gradient centrifugation, and immunological cells were harvested after cytokines stimulation. Virus infected cell model was established by H1N1 co-cultured with normal human bronchial epithelial cell line (16HBE). The optimal concentration of AD was defined by methyl-thiazolyl-tetrazolium (MTT) assay. After the virus infected cell model was established, AD was added into the medium as a treatment intervention. After 24-h co-culture, cell supernatant was collected for interferon gamma (IFN-γ) and interleukin-4 (IL-4) enzyme-linked immunosorbent assay (ELISA) detection while immunological cells for real-time polymerase chain reaction (RT-PCR).

RESULTSThe optimal concentration of AD for anti-virus effect was 250 μg/mL. IL-4 and IFN-γ in the supernatant and mRNA levels in RLRs pathway increased when cells was infected by virus, RIG-I, IFN-β promoter stimulator-1 (IPS-1), interferon regulatory factor (IRF)-7, IRF-3 and nuclear transcription factor κB (NF-κB) mRNA levels increased significantly (P<0.05). When AD was added into co-culture medium, the levels of IL-4 and IFN-γ were lower than those in the non-interference groups and the mRNA expression levels decreased, RIG-I, IPS-1, IRF-7, IRF-3 and NF-κB decreased significantly in each group with significant statistic differences (P<0.05).

CONCLUSIONSThe RLRs mediated viral recognition provided a potential molecular target for acute viral infections and andrographolide could ameliorate H1N1 virus-induced cell mortality. And the antiviral effects might be related to its inhibition of viral-induced activation of the RLRs signaling pathway.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Antiviral Agents ; pharmacology ; Cells, Cultured ; Coculture Techniques ; DEAD Box Protein 58 ; DEAD-box RNA Helicases ; genetics ; metabolism ; Dendritic Cells ; drug effects ; immunology ; virology ; Diterpenes ; pharmacology ; Fetal Blood ; cytology ; Humans ; Influenza A Virus, H1N1 Subtype ; drug effects ; immunology ; Influenza, Human ; drug therapy ; immunology ; virology ; Interferon-beta ; genetics ; metabolism ; Interferon-gamma ; metabolism ; Interleukin-4 ; metabolism ; Leukocytes, Mononuclear ; drug effects ; immunology ; virology ; Macrophages ; drug effects ; virology ; NF-kappa B ; genetics ; metabolism ; Promoter Regions, Genetic ; drug effects ; immunology ; RNA, Messenger ; metabolism ; Signal Transduction ; drug effects ; genetics ; immunology

Dendritic cells (DCs) are crucial for the induction and maintenance of tumor-specific immune responses. Studies have shown that tumor-associated DCs are immunosuppressed in some human tumors. However, phenotype and function of DCs in retinoblastoma (RB) remain unclear. RB cell supernatant (RBcs) was used to treat DCs in vitro to explore the effect of RB cells on DCs. DCs were generated from peripheral blood mononuclear cells of healthy donors. On day 5 of culture, DCs were treated with RBcs for 24 h, and then purified using magnetic beads. The maturation of DCs was induced by TNF-α or LPS. After treatment with RBcs, expression of co-stimulatory molecules CD80 and CD86 was elevated in DCs, accompanied by increased production of IL-12p70, TNF-α, IL-6, IL-1β, and IL-8 but decreased production of IL-10. RBcs neither inhibited DC maturation nor promoted DC apoptosis. Moreover, RBcs-exposed DCs stimulated allogenetic T cell proliferation and T cell-derived cytokine production. These results indicate that RBcs can improve DCs' antigen presenting function and capability to activate T cells, suggesting that RB cells may have an immunostimulatory effect on DCs, and DC-based immunotherapy may be adopted in the treatment of RB.
B7-1 Antigen ; metabolism ; B7-2 Antigen ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Culture Media, Conditioned ; pharmacology ; Cytokines ; metabolism ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Humans ; Lipopolysaccharides ; toxicity ; Retinal Neoplasms ; metabolism ; pathology ; Retinoblastoma ; metabolism ; pathology ; T-Lymphocytes ; cytology ; immunology ; metabolism ; Tumor Necrosis Factor-alpha ; pharmacology

OBJECTIVETo observe the influence of infection of murine chemokine receptor-7 recombinant lentivirus on the immunogenicity and migration of dendritic cell strain DC 2.4 cells.

METHODSDC 2.4 cells were routinely cultured. Lentiviruses carrying GFP and those with up-regulated CCR7 were constructed. DC 2.4 cells were divided into DC 2.4 group (without any treatment), GFP-DC 2.4 group (infected with GFP-carrying lentivirus), and CCR7-DC 2.4 group (infected with CCR7-carrying lentivirus labeled by GFP) according to the random number table. The expressions of surface molecules MHCII, CD80, CD86, and CCR7 were detected by flow cytometry, Western blotting, and confocal laser scanning microscope. The migration of cells was detected by chemotaxis assay in vitro. The immunogenicity of cells was detected with mixed lymphocyte reaction. LPS-DC 2.4 group was set up as positive control. Data were processed with one-way analysis of variance and t test.

RESULTSLentiviruses carrying stably-expressing CCR7 were constructed, and the transfection rate of which into DC 2.4 cells was 87.4%. There was no statistically significant difference among DC 2.4, GFP-DC 2.4, and CCR7-DC 2.4 groups in the expressions of MHC II, CD80, and CD86 as showed by flow cytometry (with F values from 0.17 to 1.19, P values all above 0.05). The protein expression of CCR7 of cells in CCR7-DC 2.4 group (45.1 ± 2.1) was obviously higher than that in DC 2.4 and GFP-DC 2.4 groups (25.3 ± 1.4, 28.6 ± 0.9, F = 162.90, P < 0.01), while the difference of which between DC 2.4 group and GFP-DC 2.4 group was not statistically significant (t = 2.20,P > 0.05). The fluorescence intensity of CCR7 in CCR7-DC 2.4 group was obviously increased compared with that of DC 2.4 group. The chemotaxis migration rate of cells in CCR7-DC 2.4 group with the influence of CCL19 was (41.0 ± 2.0)%, which was significantly higher than that of DC 2.4 and GFP-DC 2.4 groups [(6.0 ± 0.5)%, (6.8 ± 0.3)%, F = 84.21, P < 0.01]. There was no statistically significant difference between DC 2.4 group and GFP-DC 2.4 group in the migration rate (t = 0.45, P > 0.05). The absorbance values in DC 2.4, GFP-DC 2.4, CCR7-DC 2.4, and LPS-DC 2.4 groups were respectively 1.6 ± 0.4, 1.9 ± 0.4, 1.7 ± 0.4, 3.8 ± 0.4, and the differences among the former three groups were not obvious (F = 1.56, P > 0.05). The absorbance value in LPS-DC 2.4 group was obviously higher than that of the other three groups (with t values from 1.53 to 1.82, P values all below 0.01).

CONCLUSIONSDC 2.4 cells infected with efficiently CCR7-expressing lentivirus showed high chemotaxis to CCL19, but without obvious change in immunogenicity.

Animals ; Cell Line ; Cell Movement ; Dendritic Cells ; cytology ; immunology ; Lentivirus ; genetics ; Mice ; Receptors, CCR7 ; genetics ; metabolism ; Transfection

Defective dendritic cell (DC) functions have been implicated in ITP. The purpose of this study was to investigate the distribution and activation of dendritic cells in immune thrombocytopenia (ITP) patients. ITP patients were divided into 3 groups: the newly diagnosed, refractory and effective treatment group. The distributions of plasmacytoid dendritic cells (pDC) and myeloid dendritic cells (mDC) in peripheral blood, bone marrow and spleen were detected with flow cytometry. The expression level of CD80 and CD86 on surface of pDC and mDC was also detected with flow cytometry. The results indicated that the percentage of mDC was higher than that of pDC in all sites of all groups. The percentage of mDC and pDC in all site of refractory group was higher than that in newly diagnosed and effective groups, but the percentage of mDC in spleen of refractory group was obviously higher than that in other sites. The percentage of pDC was no significant different in all groups. The expression level of CD86 in all groups was higher than that of CD80, the expression level of CD80 was lower in mDC and pDC of all groups, but there was no obvious difference in all sites. The CD86 expression in all site of refractory group was higher than that in newly diagnosed and effective treatment groups, while the CD86 expression of mDC in spleen of newly diagnosed group obviously higher than that in other sites. It is concluded that the distribution abnormality of mDC and pDC exists in ITP patients, the mDC are more accumulated in spleen, and differentiation of mDC to maturity is more obvious in spleen, spleen-derived mDC significantly express CD86, spleen-derived mDC may play an important role in the pathogenesis of ITP.
Adult ; B7-1 Antigen ; metabolism ; B7-2 Antigen ; metabolism ; Dendritic Cells ; cytology ; immunology ; Female ; Humans ; Male ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; Spleen ; cytology