Adjuvants, Immunologic ; therapeutic use ; Antigen-Presenting Cells ; drug effects ; immunology ; Combined Modality Therapy ; Dendritic Cells ; drug effects ; immunology ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Immunotherapy ; Medicine, Chinese Traditional ; Neoplasms ; drug therapy ; immunology ; Phytotherapy

Collagen-induced arthritis (CIA) is mediated by self-reactive CD4+ T cells that produce inflammatory cytokines. TGF-beta2-treated tolerogenic antigen-presenting cells (Tol-APCs) are known to induce tolerance in various autoimmune diseases. In this study, we investigated whether collagen-specific Tol-APCs could induce suppression of CIA. We observed that Tol-APCs could suppress the development and severity of CIA and delay the onset of CIA. Treatment of Tol-APCs reduced the number of IFN-gamma- and IL-17-producing CD4+ T cells and increased IL-4- and IL-5-producing CD4+ T cells upon collagen antigen stimulation in vitro. The suppression of CIA conferred by Tol-APCs correlated with their ability to selectively induce IL-10 production. We also observed that treatment of Tol-APCs inhibited not only cellular immune responses but also humoral immune responses in the process of CIA. Our results suggest that in vitro-generated Tol-APCs have potential therapeutic value for the treatment of rheumatoid arthritis as well as other autoimmune diseases.
Animals ; Antigen-Presenting Cells/*drug effects/*immunology ; Arthritis, Experimental/*immunology ; Chickens ; Collagen Type II/immunology ; Immune Tolerance/drug effects ; Mice ; Mice, Inbred BALB C ; Ovalbumin/immunology ; Th1 Cells/drug effects/immunology ; Th2 Cells/*drug effects/*immunology ; Transforming Growth Factor beta2/*pharmacology

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

OBJECTIVEAntigen-presenting cells such as monocytes and dendritic cells (DCs) stimulate T-cell proliferation and activation during adaptive immunity. This cellular interaction plays a role in the growth of atherosclerotic plaques. Tanshinone II A (TSN) had been shown to decrease the growth of atherosclerotic lesions. We therefore investigated the ability of TSN to inhibit human monocyte-derived DCs and their T-cellstimulatory capacity.

METHODSDCs derived from human monocytes cultured with recombinant human interleukin (IL)-4 and recombinant human granulocyte-macrophage colony-stimulating factor were co-cultured with TSN and lipopolysaccharide for 48 h. Phosphate-buffered saline was used as a negative control. Activation markers and the capacity of DCs for endocytosis were measured by flow cytometry, and proinflammatory cytokines were measured by enzyme-linked immunosorbent assays. DCs were co-cultured with lymphocytes to measure T-cell proliferation and IL-2 secretion by mixed lymphocyte reactions.

RESULTSTSN dose-dependently attenuated DC expression of costimulatory molecules (CD86), and decreased expression of major histocompatibility complex class II (human loukocyte antigen-DR) and adhesion molecules (CD54). Moreover, TSN reduced secretion of the proinflammatory cytokines IL-12 and IL-1 by human DCs, and restored the capacity for endocytosis. Finally, TSN-preincubated DCs showed a reduced capacity to stimulate T-cell proliferation and cytokine secretion.

CONCLUSIONSTSN inhibits DC maturation and decreases the expression of proinflammatory cytokines, while impairing their capacity to stimulate T-cell proliferation and cytokine secretion. These effects may contribute to the influence of TSN on the progression of atherosclerotic lesions.

Antigen-Presenting Cells ; drug effects ; Atherosclerosis ; immunology ; pathology ; B7-2 Antigen ; metabolism ; Cell Membrane ; drug effects ; metabolism ; Cytokines ; secretion ; Dendritic Cells ; drug effects ; immunology ; secretion ; Diterpenes, Abietane ; pharmacology ; Endocytosis ; drug effects ; Flow Cytometry ; Humans ; Immunity, Cellular ; drug effects ; Inflammation Mediators ; metabolism ; Lymphocyte Activation ; drug effects

BACKGROUNDRapamycin (RAPA) is a relatively new immunosuppressant drug that functions as a serine/threonine kinase inhibitor to prevent rejection in organ transplantation. RAPA blocks activation of T-effector (Teff) cells by inhibiting the response to interleukin-2. Recently, RAPA was also shown to selectively expand the T-regulator (Treg) cell population. To date, no studies have examined the mechanism by which RAPA converts Teff cells to Treg cells.

METHODSPeripheral CD4(+)CD25(-) naive T cells were cultivated with RAPA and B cells as antigen-presenting cells (APCs) in vitro. CD4(+)CD25(-) T cells were harvested after 6 days and analyzed for expression of forkhead box protein 3 (Foxp3) using flow cytometry. CD4(+)CD25(+)CD127(-) subsets as the converted Tregs were isolated from the mixed lymphocyte reactions (MLR) with CD127 negative selection, followed by CD4 and CD25 positive selection using microbeads and magnetic separation column (MSC). Moreover, mRNA was extracted from converted Tregs and C57BL/6 naive CD4(+)CD25(+) T cells and Foxp3 levels were examined by quantitative real-time polymerase chain reaction (rt-PCR). A total of 1 x 10(5) carboxyfluorescein succinimidyl ester (CFSE)-labeled naive CD4(+)CD25(-) T cells/well from C57BL/6 mice were cocultured with DBA/2 or C3H maturation of dendritic cells (mDCs) (0.25 x 10(5)/well) in 96-well round-bottom plates for 6 days. Then 1 x 10(5) or 0.25 x 10(5) converted Treg cells were added to every well as regulatory cells. Cells were harvested after 6 days of culture and analyzed for proliferation of CFSE-labeled naive CD4(+)CD25(-) T cells using flow cytometry. Data were analyzed using CellQuest software.

RESULTSWe found that RAPA can convert peripheral CD4(+)CD25(-) naive T Cells to CD4(+)Foxp3(+) Treg cells using B cells as APCs, and this subtype of Treg can potently suppress Teff proliferation and maintain antigenic specificity.

CONCLUSIONOur findings provide evidence that RAPA induces Treg cell conversion from Teff cells and uncovers an additional mechanism for tolerance induction by RAPA.

Animals ; Antibiotics, Antineoplastic ; pharmacology ; Antigen-Presenting Cells ; drug effects ; immunology ; metabolism ; B-Lymphocytes ; drug effects ; immunology ; metabolism ; CD4-Positive T-Lymphocytes ; drug effects ; immunology ; metabolism ; Cell Proliferation ; drug effects ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Forkhead Transcription Factors ; metabolism ; Interleukin-2 Receptor alpha Subunit ; metabolism ; Interleukin-7 Receptor alpha Subunit ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Inbred DBA ; Mitomycin ; pharmacology ; Polymerase Chain Reaction ; Sirolimus ; pharmacology ; T-Lymphocytes, Regulatory ; drug effects ; immunology ; metabolism

Receptor activator of NFkappaB ligand (RANKL) is known as a key regulator of osteoclastogenesis. However, the fact that fibroblasts and periodontal ligament cells express RANKL in response to bacterial substances, suggests that RANKL may have evolved as a part of the immunity to infection. As RANKL increases the survival and activity of dendritic cells, it may have similar effects on macrophages. To address this issue, we studied the effect of RANKL on various functions of macrophages using mouse bone marrow derived macrophages. RANKL enhanced the survival of macrophages and up-regulated the expression of CD86. RANKL-treated macrophages showed increased allogeneic T cell activation and phagocytic activity compared to control cells. In addition, RANKL increased the expression of TNFalpha, MCP-1, and IL-6 but not of IL-10, IL-12, IFN-gamma, and iNOS. Collectively, RANKL augmented the activity of macrophages especially as antigen presenting cells, suggesting its new role in immune regulation.
Animals ; Antigen-Presenting Cells/cytology/*drug effects/immunology/*metabolism ; Antigens, CD86/metabolism ; Carrier Proteins/*pharmacology ; Cell Death/drug effects ; Cell Survival/drug effects ; Cells, Cultured ; Cytokines/metabolism ; Flow Cytometry ; Histocompatibility Antigens Class II/metabolism ; Inflammation Mediators ; Interferon Type II/pharmacology ; Lipopolysaccharides/pharmacology ; Macrophages/cytology/*drug effects/immunology/*metabolism ; Membrane Glycoproteins/*pharmacology ; Mice ; Mice, Inbred C57BL ; Mice, Inbred ICR ; Nitric Oxide Synthase Type II/metabolism ; Phagocytosis/drug effects ; Research Support, Non-U.S. Gov't ; T-Lymphocytes/immunology/metabolism ; Up-Regulation/drug effects/genetics

OBJECTIVETo explore the effects of large dose of Astragalus membranaceus (Astragalus) on the dentritic cell (DC) induction in vitro and augumentation by peripheral mononuclear cell (MNC) and on antigen presenting ability of DC in children with acute leukemia.

METHODSForty-four children with acute leukemia in complete remission stage were divided into two groups. Twenty patients in the Astragalus (90 g daily) group were treated with large dose of Astragalus (90 g daily) based on conventional chemotherapy for one month, while 24 patients in the control group received chemotherapy alone. MNC were extracted from peripheral blood by wall-sticking method and cultured with such cell factors as interleukin-4, gramulocyte macrophage colony stimulating factor, tumor necrosis factor-alpha for 7-8 days. Phenotype of DC was assayed by flow cytometry and antigen presenting ability of them was assayed by mixed lymphocyte reaction.

RESULTSThere was no morphological difference in MNC induced DC between the two groups. The average number of DC in Astragalus group and control group was 4.4 x 10(6) / 2.5 x 10(6) MNC and 2.6 x 10(6) / 2.5 x 10(6) MNC, respectively, showing significant difference (P < 0.001). DC in Astragalus group could stimulate the proliferation of allogeneic lymphocytes strongly, showing significant difference when compared with that in the control group (P < 0.001). Conclusion Large dose of Astragalus could increase the DC induction of MNC and enhance the antigen presenting ability of DC in acute leukemia patients.

Acute Disease ; Antigen-Presenting Cells ; cytology ; Astragalus membranaceus ; chemistry ; Cell Differentiation ; Cells, Cultured ; Child ; Child, Preschool ; Dendritic Cells ; drug effects ; immunology ; Dose-Response Relationship, Drug ; Drug Administration Schedule ; Drugs, Chinese Herbal ; pharmacology ; Female ; Humans ; Leukemia ; pathology ; Leukemia, Myeloid, Acute ; pathology ; Leukocytes, Mononuclear ; cytology ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; pathology ; Tumor Cells, Cultured