Polysaccharides extracted from various sources are natural active substances, which may lead to the activation of macrophage via multiple pathways and mechanisms. This article intends to illustrate the signaling pathways of polysaccharides from plants, fungi, algae and other sources, to identify the mechanisms on the molecular level, and to explore the novel target immunomodulatory agents.
Animals ; Humans ; Macrophage Activation ; drug effects ; immunology ; Macrophages ; drug effects ; immunology ; metabolism ; Polysaccharides ; pharmacology ; Signal Transduction

Many Chinese drugs (CHD) have showed their significant effects of integral immune-regulation, and lots of researches have conducted in recent years for exploring their mechanism from different levels, like cytological, molecular and genetic levels. In this paper, the relation between immune-regulation of CHD and Toll-like receptors/nuclear factor-kappaB (TLRs/NF-kappaB) signaling pathway was introduced in brief based upon the achievements of previous researches. It was pointed out that the two are closely related, to explore mechanism of CHD in this way is meaningful not only for further deepening the theoretical understanding of CHD's pharmacological immunoregulation, but also be practically facilitate for enhancing therapeutic efficacy of CHD and developing new CHD.
Adjuvants, Immunologic ; pharmacology ; Drugs, Chinese Herbal ; pharmacology ; Humans ; NF-kappa B ; immunology ; Signal Transduction ; drug effects ; Toll-Like Receptors ; immunology

OBJECTIVEDendritic cells an hyperinsulinemia are both implicated in the pathogenesis of atherosclerosis. The aim of this study is to explore the effect of high concentration of insulin on the maturation of monocyte-derived dendritic cells (MoDCs) and related signal transduction pathways.

METHODSHuman monocytes were purified (over 98%) using Anti-CD14 micro-beads and cultured for 5 days with DC Cellgro medium containing rhGM-CSF (100 microg/L) and rhIL-4 (20 microg/L). Immature DC were then incubated with insulin of various concentrations (0, 1, 10, 100 nmol/L) for 24 hours in the presence or absence of LY294002 (PI3K inhibitor) or PD98059 (MAPK inhibitor). Immunophenotypic expression of CD86 and CD83 were detected using flow cytometry. Endocytosis function of the MoDCs was evaluated using FITC-Dextran and MoDCs secretion IL-12, IFN-gamma and TNF-alpha were measured by ELISA.

RESULTSInsulin induced significantly higher CD83 and CD86 expressions on MoDCs in a dose-dependent manner. The endocytosis function of MoDCs were significantly inhibited and cytokine secretions of IL-12, IFN-gamma and TNF-alpha significantly increased by 10 nmol/L and 100 nmol/L insulin. These effects could be blocked by the LY294002 and PD98059.

CONCLUSIONHyperinsulinemia contributed to atherosclerosis via stimulating immune maturation of MoDCs via both PI3K and MAPK pathways.

Cell Differentiation ; drug effects ; immunology ; Cells, Cultured ; Cytokines ; metabolism ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Humans ; Insulin ; administration & dosage ; pharmacology ; Monocytes ; cytology ; Phagocytosis ; drug effects ; Signal Transduction

The progress in the research of pharmacological mechanism of anti-fibrosis traditional Chinese drugs and the effective components is summarized. It's demonstrated by pharmacological experiments that anti-fibrosis traditional Chinese drugs can inhibit the cell proliferation, regulate the cytokines and ECM, and intervente in the signal transduction.
Animals ; Cell Proliferation ; drug effects ; Cytokines ; immunology ; Drugs, Chinese Herbal ; chemistry ; therapeutic use ; Fibrosis ; drug therapy ; immunology ; metabolism ; Humans ; Signal Transduction ; drug effects

OBJECTIVETo investigate the effects of anti-CD44 mAb A3D8 on the cell proliferation of human acute monocytic leukemia cell line THP-1 and its mechanism.

METHODSCell proliferation was assayed with MTT method, the expression of CD33, CD15, CD11b, CD14, Annexin-V, caspase-3 and cell cycle with flow cytometry, and the expression of p-Akt, p-ERK, bcl-2 and p27kip1 with Western blot.

RESULTSA3D8 could remarkably inhibit the proliferation capacity of the THP-1 cells in a dosage- and time-dependent manner. THP-1 differentiation was observed when treated with A3D8 (2.0 µg/ml) for one to six days. Expression of CD33 (68.9 ± 2.0 vs 39.3 ± 1.5), CD15 (61.7 ± 5.5 vs 12.9 ± 2.6), CD11b (67.3 ± 3.8 vs 14.0 ± 2.0) and CD14 (83.0 ± 5.7 vs 8.0 ± 1.0) was significantly increased at day 4 compared with the control group (all P < 0.01). Cell cycle of the THP-1 cells was arrested in G(0)/G(1). Expression of the Annexin-V \[(32.5 ± 2.5)% vs (2.4 ± 0.3)%\] and caspase-3 \[(33.3 ± 2.5)% vs (3.6 ± 0.3)%\] was much higher than that in normal controls (all P < 0.01), and apoptosis was observed in THP-1 cells at day 5. Expression of p-Akt (0.24 ± 0.06 vs 1.20 ± 0.15), p-ERK (0.32 ± 0.05 vs 1.24 ± 0.09), and bcl-2 (0.11 ± 0.05 vs 0.65 ± 0.07) was much lower than that of the controls (all P < 0.01), while p27kip1 (1.08 ± 0.09 vs 0.10 ± 0.02) was significantly increased at day 4 (P < 0.05).

CONCLUSIONAnti-CD44 antibody can induce the differentiation and apoptosis of THP-1 cell through inhibiting PI3K/AKt and ERK1/2 signaling pathway.

Antibodies, Monoclonal ; immunology ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Hyaluronan Receptors ; immunology ; Leukemia, Monocytic, Acute ; pathology ; Signal Transduction

Antibody-based PD-1/PD-L1 blockade therapies have taken center stage in immunotherapies for cancer, with multiple clinical successes. PD-1 signaling plays pivotal roles in tumor-driven T-cell dysfunction. In contrast to prior approaches to generate or boost tumor-specific T-cell responses, antibody-based PD-1/PD-L1 blockade targets tumor-induced T-cell defects and restores pre-existing T-cell function to modulate antitumor immunity. In this review, the fundamental knowledge on the expression regulations and inhibitory functions of PD-1 and the present understanding of antibody-based PD-1/PD-L1 blockade therapies are briefly summarized. We then focus on the recent breakthrough work concerning the structural basis of the PD-1/PD-Ls interaction and how therapeutic antibodies, pembrolizumab targeting PD-1 and avelumab targeting PD-L1, compete with the binding of PD-1/PD-L1 to interrupt the PD-1/PD-L1 interaction. We believe that this structural information will benefit the design and improvement of therapeutic antibodies targeting PD-1 signaling.
Antibodies, Monoclonal ; immunology ; therapeutic use ; Antibodies, Monoclonal, Humanized ; immunology ; therapeutic use ; B7-H1 Antigen ; antagonists & inhibitors ; immunology ; Humans ; Neoplasms ; drug therapy ; immunology ; pathology ; Programmed Cell Death 1 Receptor ; antagonists & inhibitors ; immunology ; Signal Transduction ; drug effects ; immunology ; T-Lymphocytes ; immunology

Excessive activation of macrophages is implicated in various inflammatory injuries. Salidroside (Sal), one of the main bioactive components of Rhodiola Sachalinensis, has been reported to possess anti-inflammatory activities. This study aimed to examine the effect of Sal on the activation of macrophages and the possible mechanism. The lipopolysaccharide (LPS)-stimulated phrobol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophage models were established. The changes in the inflammatory profiles of THP-1-derived macrophages were determined. The results showed that Sal significantly decreased the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), interleukin-1beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) at both mRNA and protein levels in THP-1-derived macrophages, and the effect was dose-depedent. Moreover, NF-κB activation was significantly suppressed and the phosphorylation of ERK, p38 and JNK was substantially down-regulated after Sal treatment. The findings suggested that Sal can suppress the activation of LPS-stimulated PMA-differetiated THP-1 cells, as evidenced by the decreased expression of iNOS, COX2, IL-1β, IL-6 and TNF-α, and the mechanism involves the inhibition of NF-κB activation and the phosphorylation of the MAPK signal pathway.
Cell Line ; Down-Regulation ; drug effects ; genetics ; immunology ; Glucosides ; pharmacology ; Humans ; Lipopolysaccharides ; immunology ; Macrophages ; drug effects ; immunology ; Mitogen-Activated Protein Kinases ; genetics ; NF-kappa B ; genetics ; Phenols ; pharmacology ; Signal Transduction ; drug effects ; genetics ; immunology

Toll-like receptors (TLRs) are germline-encoded pattern recognition receptors (PRRs) that play a central role in host cell recognition and responses to virus infection, leading to the production of interferons (IFNs) and proinflammatory cytokines. In parallel, in order to establish an infection, viruses have to develop exclusively strategies to interfere with TLRs signaling, particularly some important adaptors activation such as MyD88, NF-kappaB, TRIF and IRFs, and suppress or escape host's antiviral immune response. In this paper, we review the latest findings on the various strategies used by viruses to modulate TLRs-mediated innate immune response, with special emphasis on immune evasion mechanism of VACV, HCV and HIV. By highlighting recent progress in these areas, we hope to convey a greater understanding of how viruses hamper TLRs signaling and how to overcome viral infection.
Animals ; Antiviral Agents ; pharmacology ; therapeutic use ; Humans ; Immunity, Innate ; drug effects ; Signal Transduction ; drug effects ; Toll-Like Receptors ; metabolism ; Virus Diseases ; drug therapy ; immunology ; metabolism ; pathology

OBJECTIVETo explore the mechanism of epimedium flavonoids (EF) in regulating immunosenescence via nuclear factor-kappa B (NF-kappaB) related signal transduction pathway.

METHODS(1) The apoptosis index (AI) of splenic lymphocyte in aged rats was monitored by flow cytometry, that of young rats was taken as control. (2) The differential expression profile of NF-kappaB related signals in aged rats allocated in the control group (aged rats, group A), the EF treated group (group B), the PDTC (a NF-kappaB inhibitor) treated group (group C) and the PDTC plus EF treated group (group D), was determined and the main significant molecules in them were analyzed with gene microarray of 96 genes related to NF-kappaB signal pathway.

RESULTSExcessive apoptosis of T lymphocyte cell was seen in aged rats, and it was significantly suppressed in group B and D. In group B, 73 genes were up-regulated to different extent, including 10 of the NF-kappaB/Rel/IB gene family, transduction signal molecule member of NIK/IKK/I B/Rel/NF-kappaB, NF-kappaB regulatory target genes, trans-membrane receptors, transcription factors, and receptor protein, etc. But the up-regulation on NF-kappaB gene family could not be seen in group C and that on others were also alleviated, while in the group D, the NF-kappaB gene family and its related transduction pathway were still activated to some extent. The NF-kappaB gene family showed a markedly common feature after EF intervention, either used alone or in combination with PDTC, i.e. the significant upregulated NF-kappaB1, NF-kappaB2, Rel B and I Bepsilon, and activated NIK/IKK/I B/Rel/NF-kappaB pathway.

CONCLUSIONEF can suppress the excessive apoptosis of splenic lymphocyte in aged rats and activate Rel/NF-kappaB/ I B/IKK and their signal transduction pathway to up-regulate NF-kappaB through adjusting I Bepsilon and I Balpha, which may be the essential mechanism of EF in rebuilding the immune homeostasis of T lymphocyte apoptosis and retarding immunosenescence.

Aging ; drug effects ; immunology ; Animals ; Apoptosis ; drug effects ; Epimedium ; chemistry ; Flavonoids ; pharmacology ; Male ; NF-kappa B ; drug effects ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; T-Lymphocytes ; cytology ; immunology

OBJECTIVETo probe matrine acting on natural killer cell (NK) activating receptor NKG2D ligands expression in CML cell line K562 and its underlying molecular mechanism.

METHODSThe expression of NKG2D ligands (major histocompatibility complex class I chain-related molecule A or B (MICA/B), UL16-binding proteins (ULBP) 1, 2, and 3 on K562 cells were analyzed before and after treated with matrine by FCM. The cytotoxic sensitivity of K562 to NK cell was detected by FCM after CFSE staining at different effect-to-target (E/T) cell ratios. The expression of signal transduction and transcriptional activator 3 (STAT3) protein as well as phosphorylated STAT3 (p-STAT3) were detected by western blot.

RESULTSAfter treatment with matrine, ULBP1 and ULBP2 expression, especially ULBP2 on K562 cells significantly increased, with mean fluorescence intensity (MFI) increasing to 615 and 1614 by 220 and 615 in the untreated cells, respectively. There was no significant change for MICA or ULBP3 expression. Matrine enhanced the susceptibility of K562 cells to NK-mediated cell lysis. At the ratio of E/T with 5:1, the proportion of the killed K562 cells increased to 32.8%, 38.1% and 40.5%, respectively (after 0.2, 0.5 and 0.8 mg/ml matrine treatment) by 29.2% in the untreated cells. The phosphorylated STAT3 protein, but not STAT3 protein, was significantly inhibited by matrine treatment in K562 cells.

CONCLUSIONMatrine induced the expression of NKG2D ligands in K562cells and enhanced the cytotoxicity of NK cells against K562, which was closely related to the inhibition of STAT3 activity in K562 cell.

Alkaloids ; pharmacology ; GPI-Linked Proteins ; immunology ; Humans ; Intercellular Signaling Peptides and Proteins ; immunology ; K562 Cells ; Quinolizines ; pharmacology ; Signal Transduction ; Up-Regulation ; drug effects