Interleukin-4 (IL-4) is a pleiotropic cytokine which plays a pivotal role in shaping immune responses. IL-4 mediates important proinflammatory functions in asthma, including the IgE isotype switch. IL-4 exerts its biological effects through binding to its receptor (IL-4R) complex, with the alpha chain as the high affinity binding subunit. Soluble IL-4R lacks the transmemberane and cytoplasmic domains, so it cannot induce cellular activation. By acting as a decoy to circulating IL-4 and neutralize its activity, its high specificity and affinity make it ideal as an IL-4 antagonist. Some companies have embarked the clinical research for asthma treatment with the sIL-4R and the result revealed well therapeutic effect. With RNA extracted from human monocyte as the template, The sIL-4R cDNA encoding the extracellular domain of IL-4R a chain was obtained by RT-PCR. Compared with the sIL-4R encoding sequence in GenBank, the nucleotide sequencing analysis indicated that there was a A-->G mutation at 148bp and the mutation caused Ile-->Val at 50th amino acid. According to the references, numerous polymorphisms have been identified in the IL-4R gene and the Ile50Val was the only known extracellular variant of human IL-4R. Then the recombinant vector pPIC9K/sIL-4R was constructed, linearized and introduced into Pichia pastoris GS115 by electroporation. The recombinant sIL-4R was identified by SDS-PAGE, Western blot and Ligand binding blot. The SDS-PAGE and Western blot analysis showed that the apparent molecular weight of expressed sIL-4R was about 30kD. And the Ligand binding blot analysis indicated the expressed sIL-4R had the biological activity. The sIL-4R, which had the biological activity, was successfully secretorily expressed in the Pichia pastoris (GS 115).
Genetic Vectors ; genetics ; Humans ; Interleukin-4 Receptor alpha Subunit ; biosynthesis ; genetics ; Pichia ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics

BACKGROUND: Interleukin (IL)-4 is a pleiotropic cytokine that plays an important role in the pathogenesis of the allergic inflammation and asthma. Upon IL-4 receptor (IL-4R) engagement, a variety of signaling mediators, such as JAK kinases and STAT-6 are activated, leading to induction of IL-4 target gene expression including CD23 and germline C epsilon transcription. The function of a membrane-proximal domain of IL-4Ra, termed ID-1, remains to be characterized to date. OBJECTIVE: To assess whether the ID-1 domain mediates the induction of IL-4 target gene expression in a STAT-6-dependent manner. METHODS: The intracellular region of IL-4Ralpha was translationally fused to the extracellular region of IL-2Rbeta to provide ligand specificity to IL-2. Acidic amino acids and serine residues in the ID-1 domain of the chimeric receptor were substituted by site-directed mutagenesis. These receptor cDNAs were stably transfected to M12.4.1 murine B lymphoma cells. Following IL-2 stimulation, wild type and mutant clones for the ID-1 motif were subjected to FACS. RNA blotting and elecroporetic mobility shift assays to address the levels of CD23, germline C epsilon and STAT-6 inductions, respectively. RESULTS: ID-1 mutant clones were defective in gene induction of CD23 and germline C epsilon in response to IL-2 stimulation, as compared with wildtype clones. Moreover, IL-2-mediated STAT-6 activation was abolished in ID-1 mutant clones. CONCLUSION: These results demonstrate that the ID-1 domain of IL-4Ra is essential to induce IL-4 target gene expression through a STAT-6-dependent pathway.
Amino Acids, Acidic ; Asthma ; Clone Cells ; DNA, Complementary ; Electrophoretic Mobility Shift Assay ; Gene Expression ; Inflammation ; Interleukin-2 ; Interleukin-4 Receptor alpha Subunit* ; Interleukin-4* ; Interleukins ; Janus Kinases ; Lymphoma ; Mutagenesis, Site-Directed ; Receptors, Interleukin-4 ; RNA ; Sensitivity and Specificity ; Serine

Asthma ; epidemiology ; genetics ; Case-Control Studies ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Interleukin-13 ; genetics ; Interleukin-4 ; genetics ; Interleukin-4 Receptor alpha Subunit ; genetics ; Male ; Polymorphism, Single Nucleotide

OBJECTIVETo investigate the expression of CD25(+) lymphocytes in nasopharyngeal carcinoma (NPC) tissue and the influence of Epstein-Barr virus (EBV) infection on CD25 expression.

METHODSImmunohistochemistry was used to detect CD25 expression in the NPC tissues and in situ hybridization employed to detect EBV infection with chronic nasopharyngitis tissue as the control sample.

RESULTSSignificant difference was noted in the expression of CD25(+) lymphocytes between NPC and chronic inflammatory tissues. The expression was higher in undifferentiated NPC than in keratinizing squamous cell carcinoma and non-keratinizing carcinomas. The NPC tissue was all EBV-positive except for one sample, which was identified as keratinizing carcinoma, but the control samples were all negative for EBV infection, which was correlated with CD25 expression.

CONCLUSIONThe expression of CD25(+) lymphocytes is higher in NPC tissues and correlated to EBV infection.

Carcinoma, Squamous Cell ; immunology ; virology ; Epstein-Barr Virus Infections ; immunology ; Female ; Herpesvirus 4, Human ; Humans ; Interleukin-2 ; immunology ; Interleukin-2 Receptor alpha Subunit ; biosynthesis ; Lymphocytes ; immunology ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; immunology ; virology

The objective of this study was to investigate the effect of human bone marrow mesenchymal stem cells (MSCs) on T lymphocyte killing K562 cells. MSCs were isolated from bone marrow and cultured, T cells were harvested by using nylon column method from peripheral blood. The T cells were co-cultured with MSCs, the phenotype expressions of T cell subsets were detected by flow cytometry. Killing effects of T cells (culture alone and co-culture with MSCs) on K562 cells were detected by LDH, expressions of IFN-gamma and IL-4 were detected by ELISA. The results showed that after T cells were co-cultured with MSCs for three days, the proportion of CD4+ and CD4+CD25+ T cells raised significantly (p<0.05) as compared with group of culture alone, but the proportion of CD8+ T cell were not significantly changed (p>0.05). In group of T cells co-cultured with MSCs, killing effects of T cells on K562 cells weakened, at the same time, expression of IFN-gamma decreased while expression of IL-4 increased. It is concluded that the MSCs weaken killing effects of T cells on K562 cells, which associates with increase of CD4+CD25+ T cell subsets and changes of IFN-gamma and IL-4 levels.
Bone Marrow Cells ; cytology ; CD4 Antigens ; immunology ; Coculture Techniques ; Humans ; Interferon-gamma ; metabolism ; Interleukin-2 Receptor alpha Subunit ; immunology ; Interleukin-4 ; metabolism ; K562 Cells ; Mesenchymal Stromal Cells ; cytology ; immunology ; T-Lymphocyte Subsets ; immunology ; metabolism ; T-Lymphocytes ; cytology ; immunology

OBJECTIVESTo investigate the internal links between immune responses and Tregs and cytokine by the expression of T regulatory cells (Tregs), Foxp3 mRNA of different response groups and the detection of cytokine secretion after hepatitis B vaccination.

METHODSBlood samples were collected in different response groups. Real-time fluorescence quantitative PCR was used to detect the expression of Foxp3 mRNA of peripheral blood mononuclear cells; The surface markers CD4 and CD25 in peripheral-blood mononuclear cells were determined by flow cytometry; ELISA tests were used to detect the production level of phytohemagglutinin (PHA) in peripheral blood mononuclear cells, IL -4, IL-12, IL-18 stimulated by HBsAg and (IFN) gamma.

RESULTS(1) Foxp3 expressions in response group and non-response group were higher before or after PHA and HBsAg were stimulated. Differences were statistically significant (P value less than 0.05) ; (2) In peripheral blood, the percentage of CD4+CD25+ Treg of CD4+ T cells in response group (0.59%+/-0.46%) was obviously lower than those in control group (1.30%+/-1.44%) ; (3) Peripheral blood mononuclear cells stimulated by PHA and HbsAg in each group, the concentration of IFNgamma in non-response group [(11.00+/-9.03) IU/ml] was markedly lower than those in response group [(38.88+/-28.16) IU/ml],and differences were statistically significant (P value less than 0.01); (4) In PHA- or HBsAg-stimulated peripheral-blood mononuclear cells, the concentrations of IL-18, IL-4 and IL-12 had no significant difference.

CONCLUSIONSTo some extent, CD4+CD25+Foxp3+ Treg cells may be involved in negative regulation of the immune responses to HBV vaccination. Immune non-response to HBV vaccination may be connected to insufficient secretion of IFNgamma; There was no correlation between the titer of anti-HBs and the expressions of IFNgamma and CD4+CD25+ Foxp3.

Adolescent ; Antibody Formation ; CD4 Antigens ; metabolism ; Female ; Forkhead Transcription Factors ; immunology ; Hepatitis B ; immunology ; prevention & control ; Hepatitis B Vaccines ; immunology ; Hepatitis B virus ; immunology ; Humans ; Interferon-gamma ; immunology ; Interleukin-12 ; immunology ; Interleukin-18 ; immunology ; Interleukin-2 Receptor alpha Subunit ; metabolism ; Interleukin-4 ; immunology ; Male ; T-Lymphocytes, Regulatory ; immunology ; Young Adult

Dendritic cells (DCs) comprise two functionally distinct subsets: plasmacytoid DCs (pDCs) and myeloid DCs (mDCs). pDCs are specialized in rapid and massive secretion of type I interferon (IFN-I) in response to nucleic acids through Toll like receptor (TLR)-7 or TLR-9. In this report, we characterized a CD56(+) DC population that express typical pDC markers including CD123 and BDCA2 but produce much less IFN-I comparing with pDCs. In addition, CD56(+) DCs cluster together with mDCs but not pDCs by genome-wide transcriptional profiling. Accordingly, CD56(+) DCs functionally resemble mDCs by producing IL-12 upon TLR4 stimulation and priming naïve T cells without prior activation. These data suggest that the CD56(+) DCs represent a novel mDC subset mixed with some pDC features. A CD4(+)CD56(+) hematological malignancy was classified as blastic plasmacytoid dendritic cell neoplasm (BPDCN) due to its expression of characteristic molecules of pDCs. However, we demonstrated that BPDCN is closer to CD56(+) DCs than pDCs by global gene-expression profiling. Thus, we propose that the CD4(+)CD56(+) neoplasm may be a tumor counterpart of CD56(+) mDCs but not pDCs.
Biomarkers ; metabolism ; CD56 Antigen ; genetics ; immunology ; Cell Lineage ; genetics ; immunology ; Dendritic Cells ; immunology ; metabolism ; pathology ; Gene Expression ; Hematologic Neoplasms ; genetics ; immunology ; pathology ; Humans ; Immunophenotyping ; Interferon Type I ; biosynthesis ; metabolism ; Interleukin-12 ; biosynthesis ; metabolism ; Interleukin-3 Receptor alpha Subunit ; genetics ; immunology ; Lectins, C-Type ; genetics ; immunology ; Membrane Glycoproteins ; genetics ; immunology ; Myeloid Cells ; immunology ; metabolism ; pathology ; Receptors, Immunologic ; genetics ; immunology ; Terminology as Topic ; Toll-Like Receptor 4 ; genetics ; immunology ; Toll-Like Receptor 7 ; genetics ; immunology ; Toll-Like Receptor 9 ; genetics ; immunology

The study was aimed to detect the expressions of costimulatory molecules on CD3(+)CD4(+) T cells so as to accumulate informations for investigation of mechanism of myelodysplastic syndrome. 11 healthy blood donors as control and 38 patients with MDS de novo were studied. 38 MDS patients were divided into RA/RARS group and RAEB/RAEB-t group according to FAB classification. The expressions of CD28, CD154, CTLA-4, PD-1, CD25 on CD3(+)CD4(+) T cells in peripheral blood were detected by FCM. The results indicated that as compared with normal controls, the expression of CD28 in MDS patients decreased, and CD154 increased. The percentages of CTLA-4, PD-1 and CD25 in MDS were obviously higher than that in normal controls; the differences of CTLA-4, PD-1 and the ratio of CTLA-4/CD28 between RAEB/RAEB-t and RA/RARS were more significant with progressing of MDS. In conclusion, the expressions of costimulatory molecule in MDS patients were abnormal, which may be involved in the pathogenesis of MDS.
Adult ; Antigens, CD ; metabolism ; Apoptosis Regulatory Proteins ; metabolism ; CD28 Antigens ; metabolism ; CD40 Ligand ; metabolism ; CTLA-4 Antigen ; Case-Control Studies ; Female ; Humans ; Interleukin-2 Receptor alpha Subunit ; metabolism ; Lymphocyte Count ; Male ; Middle Aged ; Myelodysplastic Syndromes ; immunology ; metabolism ; Programmed Cell Death 1 Receptor ; T-Lymphocytes ; immunology ; metabolism ; Young Adult

OBJECTIVETo investigate the toxicity of anti-CD25 monoclonal antibody (mAb) to rat cornea and its effects on the cytokines in the aqueous humour after penetrating keratoplasty (PKP), thereby evaluating the effect of anti-CD25 mAb in preventing corneal allograft rejection.

METHODSThe corneal toxicity of anti-CD25 mAb at 50, 100 and 200 microg administered via subconjunctival injection was evaluated in 12 SD rats by histological examination and transmission electron microscopy. Another 93 SD rats were randomized into 5 groups, and transplantation of corneal allograft from Wistar rats was performed in 4 groups with the other group as the normal control. The 4 allograft groups were treated with saline, 100 microg anti-CD25 mAb, 100 microg anti-CD25 mAb with 50 microg dexamethasone, and 50 microg dexamethasone, respectively. The graft rejection was observed, the aqueous humour levels of IFN-gamma and IL-4 were measured with ELISA, and IFN-gamma mRNA expressions in the grafts detected with RT-PCR.

RESULTSanti-CD25 mAb at 50 or 100 microg did not show significant toxicity on the cornea, but at 200 microg, the mAb caused swelling of the corneal stromal cells and endothelial cells. After corneal allograft transplantation, a significant delay in allograft rejection was observed in the 3 groups with mAb or dexamethasone treatment as compared with that in saline group (P<0.05). IFN-gamma mRNA expression in the allograft on days 11 after PKP and in the aqueous humour on days 6 and 11 was markedly increased in saline group compared with that in the 3 treatment groups (P<0.05). The mean IL-4 level in the aqueous humour was significantly higher in the mAb group than in saline group (P<0.05), but markedly lower in anti-CD25 mAb+dexamethasone and dexamethasone groups than in anti-CD25 mAb group (P<0.05).

CONCLUSIONSAnti-CD25 mAb at 20 and 100 microg does not obviously affect the rat corneas. Anti-CD25 mAb inhibits IFN-gamma expression and promotes IL-4 the expression to reduce corneal allograft rejection, whereas anti-CD25 mAb with low-dose dexamethasone inhibits both IFN-gamma and IL-4 expressions to more effectively promote the graft survival.

Animals ; Antibodies, Monoclonal ; pharmacology ; Aqueous Humor ; drug effects ; metabolism ; Cytokines ; metabolism ; Female ; Graft Rejection ; prevention & control ; Interferon-gamma ; metabolism ; Interleukin-2 Receptor alpha Subunit ; immunology ; Interleukin-4 ; metabolism ; Keratoplasty, Penetrating ; methods ; Male ; Peptide Fragments ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar

This study investigated the effect of arctigenin (Arc) on the cell activation, cytokines expression, proliferation, and cell-cycle distribution of mouse T lymphocytes. Mouse lymphocytes were prepared from lymph node and treated with Phorbol-12-myristate-13-acetate (PMA)/Ionimycin (Ion) and/or Arc. CD69, CD25, cytokines, proliferation and cell cycle were assayed by flow cytometry. The results showed that, at concentrations of less than 1.00 micromol x L(-1), Arc expressed non-obvious cell damage to cultured lymphocytes, however, it could significantly down-regulate the expression of CD69 and CD25, as well as TNF-alpha, IFN-gamma, IL-2, IL-4, IL-6 and IL-10 on PMA/Ion stimulated lymphocytes. At the same time, Arc could also inhibit the proliferation of PMA/Ion-activated lymphocytes and exhibited lymphocyte G 0/G1 phase cycle arrest. These results suggest that Arc possesses significant anti-inflammatory effects that may be mediated through the regulation of cell activation, cytokines expression and cell proliferation.
Animals ; Anti-Inflammatory Agents ; isolation & purification ; pharmacology ; Antigens, CD ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; metabolism ; Arctium ; chemistry ; Cell Cycle Checkpoints ; drug effects ; Cell Proliferation ; drug effects ; Cytokines ; metabolism ; Female ; Furans ; isolation & purification ; pharmacology ; Interferon-gamma ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-2 ; metabolism ; Interleukin-2 Receptor alpha Subunit ; metabolism ; Interleukin-4 ; metabolism ; Interleukin-6 ; metabolism ; Ionomycin ; pharmacology ; Lectins, C-Type ; metabolism ; Lignans ; isolation & purification ; pharmacology ; Lymphocyte Activation ; drug effects ; Mice ; Mice, Inbred BALB C ; Plants, Medicinal ; chemistry ; T-Lymphocytes ; cytology ; drug effects ; immunology ; Tetradecanoylphorbol Acetate ; pharmacology ; Tumor Necrosis Factor-alpha ; metabolism