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

OBJECTIVETo study the effect of interleukin (IL)-27 on INF and IL-4 activities in children with asthma.

METHODSThe levels of IFN-gamma and IL-4 in culture supernatants of peripheral blood mononuclear cells (PBMCs) from 23 asthmatic children were measured using ELISA. PBMCs were cultured with recombinant IL-27 (5 ng/mL or 0.5 ng/mL) for 12 hrs in vitro.

RESULTSIFN-gamma levels in both 5 ng/mL and 0.5 ng/mL IL-27 treatment groups (85.9+/-12.2 and 8.9+/-2.3 microg/L, respectively) increased compared with those in the cytokine stimulated control group (P<0.01, P<0.05 respectively). The group treated with 5 ng/mL IL-27 had decreased significantly IL-4 levels compared with the cytokine stimulated control group (15.0+/-1.9 microg/L vs 77.0+/-15.6 microg/L; P<0.01).

CONCLUSIONSIL-27 may be involved in the pathogenesis of asthma. It may affect Th1/Th2 cell activities and might be a new option for the treatment of asthma.

Asthma ; immunology ; Cells, Cultured ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Interferon-gamma ; biosynthesis ; Interleukin-17 ; pharmacology ; Interleukin-4 ; biosynthesis ; Leukocytes, Mononuclear ; immunology ; Male ; Recombinant Proteins ; pharmacology

RT-PCR was used to clone DNA fragment of the extracellular domain of 4-1BBL from human THP-1 cells (human monocyte), and the expression vector pAYZ4-1BBL was constructed by cloning the extracellular domain of 4-1BBL into the expression vector pAYZ. The extracellular domain of 4-1BBL was expressed in E. coli 16C9 and purified by affinity chromatography. SDS-PAGE and Western blot analysis showed that the relativae molecular weight of soluble 4-1BBL is 22kD which was consistent with the theoretically predicted value. So far as we know, it is the first time that the soluble expression of 4-1BBL in E. coli was achieved 4-1BBL induced a significant release of IL-2 in stimulated Jurkat cells after 48h incubation, especially in the presence of tumor cell. At the same time the apoptosis level of Jurkat cell reduce more than 50%. In conclusion, 4-1BBL may be useful in cancer immunotherapy.
4-1BB Ligand ; biosynthesis ; genetics ; Apoptosis ; genetics ; Cell Line ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Extracellular Space ; metabolism ; Humans ; Interleukin-2 ; biosynthesis ; Jurkat Cells ; Recombinant Proteins ; biosynthesis ; genetics

OBJECTIVETo study the role of MEKK2 on the production of IL-2 in Jurkat cells stimulated by PHA/anti-CD28 antibody.

METHODSThe MEKK2 and JNK kinase activities were measured in both dominant negative MEKK2 Jurkat (dnMEKK2 Jurkat) cells and parental Jurkat cells. The AP(1) and IL-2 promotor activities were measured by luciferase activity assay. The IL-2 mRNA and protein were detected by RT-PCR and Western blot.

RESULTSAfter stimulation by PHA/anti-CD28, JNK was activated in parental Jurkat cells but not in dnMEKK2 Jurkat cells. The luciferase report gene activities of AP1 and IL-2 promotors were increased by 4- and 5-folds in parental cells whereas only by 1 fold in dnMEKK2 Jurkat cells. The level of IL-2 mRNA and IL-2 protein were increased in parental Jurkat cells but not in dnMEKK2 Jurkat cells.

CONCLUSIONMEKK2 plays an important role on the production of IL-2 in Jurkat cell stimulated with PHA/anti-CD28 antibody. It is a potential drug target for the treatment of GVHD and autoimmune disease.

Humans ; Interleukin-2 ; biosynthesis ; genetics ; Jurkat Cells ; MAP Kinase Kinase 4 ; metabolism ; MAP Kinase Kinase Kinase 2 ; metabolism ; physiology

Childhood minimal change nephrotic syndrome (MCNS) has often been associated with allergic symptoms such as urticaria, bronchial asthma, atopic dermatitis, allergic rhinitis and elevated IgE levels and referred to involve immune dysfunction. Fc epsilon RII is known to be involved in IgE production and response. Interleukin-4 is being recognized as a major cytokine up-regulating IgE production. Hence the present study is aimed at investigating the role of interleukin-4 and Fc epsilon RII in the pathogenesis of MCNS. IgE was measured by ELISA. Fc epsilon RII was analyzed by fluorescence activated cell scanner (FAC-scan) by double antibody staining with anti Leu16-FITC and anti Leu20-PE. Soluble IgE receptor was measured by ELISA using anti CD23 antibody (3-5-14). Interleukin-4 activities were measured by CD23 expression on purified human tonsillar B cells. Serum IgE levels were significantly higher in MCNS (1,507 +/- 680 IU/dl) than in normal controls (123 +/- 99.2 IU/dl). A significantly higher expression of membrane Fc epsilon RII was noted for MCNS (41 +/- 12%) than that in normal controls (18 +/- 6.2%) (p < 0.001). Soluble CD23 levels were also significantly higher in MCNS (198 +/- 39.3%) than in normal controls (153 +/- 13.4) (p < 0.01). Interleukin-4 activity in sera of MCNS (12U/ml) was also significantly higher than normal controls (4.5U/ml). These results indicate that increased production of Fc epsilon RII and interleukin-4 may play an important role in the pathogenesis of MCNS.
B-Lymphocytes/immunology ; Child ; Humans ; Immunoglobulin E/blood ; Interleukin-4/*physiology ; Nephrosis, Lipoid/*etiology/physiopathology ; Receptors, IgE/biosynthesis/*physiology ; Solubility

The relationship between T cell immunoglobulin domain and mucin domain protein 3 (Tim-3)/Galectin (Gal)-9 pathway and recurrent spontaneous abortion (RSA) was studied. Thirty-one pregnant women with RSA and 27 normal early gravidas were investigated to detect the levels of Tim-3 and Gal-9 in villi and deciduas by Western blotting. Meanwhile, the concentration of interleukin (IL)-4 and IL-12 in peripheral blood plasma was determined by ELISA in 25 healthy fertile non-pregnant controls, the normal early gravidas and pregnant women with RSA mentioned above, respectively. It was found that the relative expression levels of Tim-3 and Gal-9 in villi and deciduas were significantly increased in pregnant women with RSA as compared with those in the normal early gravidas. The concentration of IL-4 in peripheral blood plasma of pregnant women with RSA was lower than that of the normal early gravidas (P<0.05) and healthy fertile non-pregnant controls (P<0.05), but that of IL-2 in pregnant women with RSA was significantly higher than that of the normal early gravidas (P<0.05) and healthy fertile non-pregnant controls (P<0.05). It was suggested that the overexpression of Tim-3/Gal-9 pathway may be related to the pathogenesis of RSA.
Abortion, Spontaneous ; metabolism ; pathology ; Adolescent ; Adult ; Chorionic Villi ; metabolism ; pathology ; Female ; Galectins ; biosynthesis ; Hepatitis A Virus Cellular Receptor 2 ; Humans ; Interleukin-12 ; blood ; Interleukin-4 ; blood ; Membrane Proteins ; biosynthesis ; Pregnancy ; Pregnancy Proteins ; biosynthesis ; Up-Regulation

AIMTo study the effects of ginsenoside-Ro on cell proliferation and cytokine production in murine splenocytes.

METHODSThe effect of ginsenoside-Ro on murine splenocytes proliferation was studied using [3H] thymidine incorporation assay. Effects of ginsenoside-Ro on the production of cytokines interleukin-2 (IL-2), interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) from murine splenocytes were detected by ELISA method. Effects of ginsenoside-Ro on mRNA level of Th1 cytokine IFN-gamma and Th2 cytokine IL-4 were evaluated by reverse transcription polymerase chain reaction (RT-PCR) analysis.

RESULTSGinsenoside-Ro showed no mitogenic effect on unstimulated murine splenocytes. It enhanced the proliferation of Con A-induced murine splenocytes and the production of IL-2 at concentrations of 1-10 micromol x L(-1). Moreover, ginsenoside-Ro increased the production and expression of Th2 cytokine IL-4 and decreased the production and expression of Th1 cytokine IFN-gamma in Con A-induced murine splenocytes at concentrations of 2-10 micromol x L(-1).

CONCLUSIONGinsenoside-Ro showed immunomodulatory effects by regulating the production and expression of Th1/Th2 cytokines in murine splenocytes.

Animals ; Cell Proliferation ; drug effects ; Ginsenosides ; isolation & purification ; pharmacology ; Interferon-gamma ; biosynthesis ; genetics ; Interleukin-2 ; metabolism ; Interleukin-4 ; biosynthesis ; genetics ; Male ; Mice ; Mice, Inbred BALB C ; Panax ; chemistry ; Plants, Medicinal ; chemistry ; RNA, Messenger ; biosynthesis ; genetics ; Spleen ; cytology ; metabolism

OBJECTIVETo investigate whether GM-CSF can enhance the antiviral effect of HBsAg DNA vaccine.

METHODSDivided animals into 8 groups. Group A: pcDNA3.1-S 100microg; Group B: pcDNA3.1-GM-CSF-S 100microg; Group C: pcDNA3.1-S-GM-CSF 100microg; Group D: pcDNA3.1-S 50microg + pcDNA3.1-GM-CSF 50microg; Group E: pcDNA3.1-GM-CSF 100microg; Group F: recombinant HBsAg vaccine 1microg; Group G: pcDNA3.1,100microg; Group H: PBS 100microl. Serum HBsAg level and concentration of IL-2, IL-4 and IFN-gamma were examined using commercial ELISA kit. The [3H] thymidine incorporation into DNA of Spleen cells was measured; HBsAg expression of hepatocytes from HBV-transgenic mice was assessed using immunohistochemical analysis.

RESULTSSerum HBsAg level was lower and concentration of IL-2, IFN-gamma and SI was higher in mice immunized with pcDNA3.1-GM-CSF-S than those from mice immunized with pcDNA3.1-S and other groups (F=11.262, P<0.01, F=8.147, P<0.01, F=62.275, P<0.01, F=116.28, P<0.01. Less Hepatic HBsAg expression and decline of pcDNA3.1-GM-CSF-S of mice immunized with pcDNA3 were observed in comparison with control groups (F=41.439, P<0.01). Liver histological analysis showed no evidence of necrosis or inflammation in various groups.

CONCLUSIONThe plasmid co expressing GM-CSF and HBsAg could improve HBsAg-specific humoral and cellular immune responses induced by plasmid encoding HBsAg alone and enhance HBsAg DNA vaccine antivirus effect.

Animals ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B Vaccines ; immunology ; Interferon-gamma ; biosynthesis ; Interleukin-2 ; biosynthesis ; Interleukin-4 ; biosynthesis ; Lymphocyte Activation ; Male ; Mice ; Mice, Transgenic ; Plasmids ; Vaccines, DNA ; immunology

OBJECTIVETo observe the TH cell subset function in children with recurrent tonsillitis (RT) at the remission stage and to study the effects of astragalus membranacus (AM) on TH cell subset function.

METHODSThe peripheral blood mononuclear cells (PBMC) from 27 children with RT at the remission stage were stimulated with either phytohemagalutinin (PHA) (RT-PHA group) or PHA together with AM (RT-AM group) and were then cultured in vitro for 48 hrs. The samples from 21 healthy children stimulated with PHA were used as the Control group. The levels of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in the supernatants of PBMC were detected using ELISA.

RESULTSThe IFN-gamma level and the ratio of IFN-gamma/IL-4 in the RT-PHA group were statistically lower than those in the Control group (P < 0.01). The level of IFN-gamma and the ratio of IFN-gamma/IL-4 in the RT-AM group were markedly higher than those in the RT-PHA group (P < 0.01), but were significantly lower than those in the Control group (P < 0.05). There were no differences in the IL-4 level among the three groups.

CONCLUSIONSTH1 cell subset dysfunction may exit in RT children at the remission stage, suggesting that TH1 cell subset dysfunction plays an important role in the pathogenesis of RT. AM can improve TH1 cell subset function and therefore shows an important significance in treating RT.

Adolescent ; Astragalus membranaceus ; Child ; Child, Preschool ; Female ; Humans ; Interferon-gamma ; biosynthesis ; Interleukin-4 ; biosynthesis ; Male ; Phytohemagglutinins ; pharmacology ; Recurrence ; Th1 Cells ; immunology ; Th2 Cells ; immunology ; Tonsillitis ; etiology ; immunology

A DNA fragment encoding human interleukin 4 was obtained by PCR from pORF-hIL4 plasmid. The amplified fragment was inserted into prokaryotic expression vector PQE60 and recombinant protein was expressed in E. Coli M15 by adding isopropyl-beta-D-thiogalactoside (IPTG). The hIL-4 protein was present as insoluble inclusion bodies in the bacterial extract. After denaturation of inclusion bodies with 5 mol/L guanidine hydrochloride, the supernate was diluted to get renaturized. Then dialysis and Ni chelating chromatography were used for purification. TF-1 proliferation assay of recombinant human interleukin 4 was performed, and then rhIL-4 was fit to be used for proliferation of human dendritic cells from monocyte in vitro.
Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; Humans ; Inclusion Bodies ; metabolism ; Interleukin-4 ; biosynthesis ; genetics ; Protein Folding ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification