The porcine interferon-gamma (PoIFN-gamma) gene, in which the sequence encoding signal peptide was replaced by that of the alpha-factor of Saccharomyces cerevisiae, was cloned into Pichia pastoris expression vector pPIC9K. The recombinant plasmid pPIC9K-alpha-PoIFN-gamma was then transformed into Pichia pastoris GS115 cells by electroporation and stable multicopy recombinant Pichia pastoris strains were selected by G418 resistance. Two recombinants of multiple inserts were obtained. SDS-PAGE and Western blot assays of culture broth from a methanol-induced expression strain demonstrated that recombinant PoIFN-gamma, 17kD and 23kD proteins, were secreted into the culture medium. Target proteins, 60% of total proteins, were obtained in the culture medium at the concentration of 108 mg/L. This is the first secreted expression of porcine interferon-gamma gene in Pichia pastoris.
Animals ; Electroporation ; Interferon-gamma ; biosynthesis ; genetics ; Pichia ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; Swine ; genetics

The total RNA was extracted from peripheral blood mononuclear cells (PBMC) which was isolated from Meishan porcine and induced with concanavaline A (ConA), then the porcine interferon gamma gene (PoIFNgamma, 501bp) was amplified by RT-PCR. The result of sequencing demonstrated that the amplified PoIFNgamma had 100% nucleotide homology with the other porcine IFNgamma sequence published on GenBank. The objective gene (PoIFNgamma) was inserted into adenoviral shuttle vector, pShuttle-CMV, to construct recombinant plasmid pSh-PoIFNgamma. And it was co-electrotransformated with adenoviral skeletal vector pAdEasy-1 into competent cells of BJ5183. The transforms were cultured at 37 degrees C for 24h on kanamycin resistance plate and selected for smaller colonies. Then, the extracted recombinant plasmid was named pAd-Sh-PoIFNgamma, which was confirmed by Pac I digestion, and transformed into XL10-Glod(r) for copious preparation. pAd-Sh-PoIFNgamma linearized with Pac I was co-transfected with liposome into 293 package cell-line. After 7d-10d, the typical cytopathic effect indicated that recombinant adenoviral genome (deleted with E1 and E3 genes) carrying PoIFNgamma was successfully packaged into intact virion. The recombinant virion was successively seeded to the 10th generation and the viral genome was extracted from each generation by PCR. The antiviral activity of PoIFNgamma was tested by CPE50 method. The results showed that the PoIFNgamma expressed by adenovirus had high antiviral activity, which was 1.3 x 10(6) U/mL against VSV in MDBK cells. The results demonstrated that the recombinant adenovirus carrying PoIFNgamma could be stably passaged.
Adenoviridae ; genetics ; Animals ; Antiviral Agents ; pharmacology ; Interferon-gamma ; genetics ; pharmacology ; Recombinant Proteins ; biosynthesis ; pharmacology ; Swine

In order to study PBD-2 and PoIFNgamma, the chimeric gene PBD-2-PoIFNgamma was synthesized by overlap extension PCR, and amplified PoIFNgamma on the basis of this sequence, then cloned into yeast expression vector pPICZalphaA separately to get the recombinant plasmid pPICZalphaA-PBD-2-PoINFgamma and pPICZalphaA-PoINFgamma. The recombinant plasmid was digested by Sac I and introduced into Pichia pastoris X33 cells by electroporation. Positive clones were screened and cultivated in BMMY medium containing 0.5% methanol for 72 h. SDS-PAGE and Western blotting analysis showed that the screened recombinant could secrete PBD-2-PoINFgamma and PoINFgamma separately. The activity of fusion protein was not detected by cytopathic effect inhibition assay and agar diffusion assay, but detected obvious antiviral activity of PoINFgamma. The helix and random coil contents was showed vary greatly between PoIFNgamma and PBD-2-PoLNFgamma by circular dichroism analysis. It was speculated that the fusion protein was not correctly folded and may affect the activity of PBD-2-PoINFgamma.
Animals ; Genetic Vectors ; genetics ; Interferon-gamma ; biosynthesis ; genetics ; Pichia ; genetics ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; chemistry ; genetics ; Swine ; beta-Defensins ; biosynthesis ; genetics

BACKGROUNDStudies of highly exposed persistently seronegative (HEPS) individuals may provide valuable information on mechanisms of protection and on vaccine design. Cellular immune responses play a critical role in containing human immunodeficiency virus. However, the cellular immune responses in HEPS individuals have not been thoroughly assessed at the entire viral genome level.

METHODSTen HEPS Chinese with a history of frequent penetrative vaginal intercourse (mean frequency, at least once a week), with some unprotected sexual contact occurring in the weeks or days immediately before enrollment, 25 HIV-1 seropositive individuals, 10 HIV-1-seronegative healthy individuals with low-risk sexual behavior and no history suggestive of exposure to HIV-1 infection were enrolled. HIV-1-specific T cell responses were comprehensively analyzed by an interferon-gamma Elispot assay against 770 overlapping peptides spanning all HIV-1 proteins.

RESULTSHIV-1-specific T-cell responses of interferon-gamma secretion were identified in 3 (30%) out of 10 HEPS individuals; the specific cytotoxic T lymphocytes were targeted at Pol (2/10), Env (2/10), and Tat (1/10). HIV-1-specific T-cell responses of interferon-gamma secretion were identified in 20 (80%) out of 25 seropositive intravenous drug users (IDUs), revealing that all HIV-1 proteins and protein subunits could serve as targets for HIV-1-specific CD8(+) T cell responses with 85% recognizing Gag, 80% recognizing Nef, 75% recognizing Pol, 60% recognizing Env, 55% recognizing Vpu, 45% recognizing Vpr, 20% recognizing Vif, 20% recognizing Tat and 15% recognizing Rev in these seropositive individuals. None of the seronegative healthy individuals gave the positive T-cell responses.

CONCLUSIONSAbout 30% of HEPS Chinese mounted HIV-1 specific T cell immune responses. Cell-mediated immunity against HIV-1 may be developed through non-productive infections.

Adult ; Female ; HIV Seronegativity ; immunology ; HIV-1 ; immunology ; Humans ; Interferon-gamma ; biosynthesis ; Male ; Receptors, CCR5 ; genetics ; T-Lymphocytes, Cytotoxic ; immunology

Interferons (IFNs) are natural proteins produced by wide variety of cells in response to viral infection or other biological inducers, and they execute diversified functions as antiviral defense, immune activation and cell growth regulation. Four genes encoding porcine interferons (PoIFN), PoIFN-alpha, PoIFN-gamma, PoIFN-alphagamma or PolFN-omega, were cloned and sequenced. The four types of porcine interferon genes were subcloned into the pET-His vector, and expressed in Escherichia coli Rosetta (DE3). The recombinant products were purified and renaturalized from inclusion bodies to obtain a native state of well biological activity. Antiviral activity assays for porcine interferons were performed and evaluated by standard procedures in following cell/virus test systems: Marc-145/PRRSV, Marc-145/VSV, PK-15/VSV, Vero/VSV or MDBK/VSV. The data showed that both PoIFN-alpha and PoIFN-alpagamma demonstrated significant antiviral activities, and the titer of them against PRRSV was up to 10(8) U/mg. PoIFN-gamma had approximately half or one-thirds antiviral activity of PoIFN-alpha. PoIFN-omega showed inconspicuous antiviral activity.
Amino Acid Sequence ; Animals ; Antiviral Agents ; pharmacology ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Interferon Type I ; biosynthesis ; genetics ; pharmacology ; Interferon-gamma ; biosynthesis ; genetics ; pharmacology ; Molecular Sequence Data ; Porcine respiratory and reproductive syndrome virus ; drug effects ; Recombinant Proteins ; biosynthesis ; genetics ; pharmacology ; Swine

To investigate the value of apoptosis of the allo-antigen specific T cells induced by Fas/FasL pathway in preventing graft-versus-host disease (GVHD), the CD34+ cells transfected with FasL or not, used as stimulus cells, were mixed with allo-antigen specific T lymphocytes in presence or absence of IFN-gamma and IL-2. After 5 days, apoptosis of T cells was detected by TdT nick end mediated dUTP labeling (TUNEL) and flow cytometry (FCM). The affects of these two cytokines on CD34+ cells in the graft were also compared. The ratio of apoptosis of T cells was 12.1+/-1.5% when CD34+ cells transfected with FasL was used as stimulus cells, much higher than that of CD34+ cells non-transfected (3.2+/-1.1%, P<0.01). And in presence of IFN-gamma or IL-2, the ratio reached 20.1+/-2.3%, 17.6+/-1.3% respectively (P<0.01). However, IFN-gamma up-regulated Fas expression of CD34+ cells and increased the sensibility of CD34+ cells to soluble FasL (sFasL); IL-2 showed no such effect. It is possible to induce apoptosis of the allo-antigen specific T cells of grafts activated by allo-antigen by exogenous Fas ligand expressed on recipient cells and this might provide a new approach for preventing GVHD and IL-2 may be more suitable for clinical application.
Antigens, CD34 ; biosynthesis ; immunology ; Apoptosis ; Cytotoxicity, Immunologic ; DNA, Complementary ; genetics ; Fas Ligand Protein ; Graft vs Host Disease ; prevention & control ; Interferon-gamma ; biosynthesis ; immunology ; Interleukin-2 ; biosynthesis ; immunology ; Membrane Glycoproteins ; biosynthesis ; immunology ; T-Lymphocytes ; cytology ; physiology ; fas Receptor ; biosynthesis ; immunology

To investigate the role of Interleukin-17 (IL-17), Interferon-gamma (IFN-gamma), and macrophage inflammatory protein-3 alpha (MIP-3alpha) in the pathogenesis of psoriasis, reverse transcriptase-polymerase chain reaction (RT-PCR) was used to semi-quantitatively analyze the mRNA expression of IL-17, IFN-gamma, and MIP-3alpha in 31 psoriatic lesions and 16 normal skin tissues. The results showed that the mRNA of the three cytokines was present in all specimens. And the expression level of IL-17 mRNA in skin lesions was 1.1416 +/- 0.0591, which was significantly higher than that in normal controls (0.8788 +/- 0.0344, P<0.001). The expression levels of IFN-gamma mRNA were 1.1142 +/- 0.0561 and 0. 9050 +/- 0.0263, respectively, with significant difference (P<0.001). And the expression levels of MIP-3alpha mRNA in psoriatic lesions was 1.1397 +/- 0.0521, which was markedly higher than that in normal controls (0.8681 +/- 0.0308, P<0.001). These findings indicate that up-regulated expression of IL-17, IFN-gamma, and MIP-3alpha might be involved in the pathogenesis of psoriasis.
Adolescent ; Adult ; Aged ; Chemokine CCL20 ; Chemokines, CC ; biosynthesis ; genetics ; Female ; Humans ; Interferon-gamma ; biosynthesis ; genetics ; Interleukin-17 ; biosynthesis ; genetics ; Macrophage Inflammatory Proteins ; biosynthesis ; genetics ; Male ; Middle Aged ; Psoriasis ; metabolism ; RNA, Messenger ; biosynthesis ; genetics

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

OBJECTIVETo explore the immunoregulatory effects of human amniotic mesenchymal cells (hAMCs) on allogeneic peripheral blood lymphocytes.

METHODSThe hAMCs were isolated from abandoned human amnion. Peripheral blood mononuclear lymphocytes (PBMLs) were separated from healthy donors by density gradient centrifugation. Then, PBMLs were treated with phytohemagglutinin (PHA) and different concentrations of hAMCs. Proliferation effect of PBMLs was tested using MTS assay, and production of IFN-gamma and TNF-alpha by PBMLs was detected by ELISA.

RESULTShAMCs could remarkably inhibit the lymphocytes proliferation. When the ratios of hAMCs to PBMLs were 0.05: 1, 0.10 :1, 0.20: 1, the inhibitory rates of PBMLs proliferation were 16.91%, 20.83% and 28.19%, respectively. HAMCs also decreased the production of IFN-gamma and TNF-alpha by PBMLs in a dose-dependent manner (P<0.01).

CONCLUSIONSHAMCs could inhibit the proliferation of allogeneic lymphocytes and reduce secretion of IFN-gamma and TNF-alpha, which might be one of the mechanism for prevention and remission of transplant rejection.

Amnion ; cytology ; Cell Proliferation ; Humans ; Immune Tolerance ; Interferon-gamma ; biosynthesis ; Lymphocyte Activation ; immunology ; Lymphocytes ; cytology ; drug effects ; immunology ; Mesoderm ; cytology ; Phytohemagglutinins ; immunology ; Tumor Necrosis Factor-alpha ; biosynthesis

In order to study T-bet function in mouse cells, a novel retroviral vector expressing mouse T-bet and reporter gene Thy1.1 was constructed. Retrovirus particles were then produced by transfection of the recombinant retroviral plasmid into a packaging cell line Platinum-E. The recombinant retrovirus played considerable infection ability. T-bet expression was then identified by FACS after infection of CD4+ primary T cells from T-bet knockout mouse with recombinant retrovirus. To determine if exogenous expressing T-bet has normal function, we checked the expression level of T-bet target gene, Ifng. IFN-y expression was upregulated in the T-bet knockout T cells infected with recombinant retrovirus. In conclusion, we successfully constructed an effective mouse T-bet recombinant retroviral vector.
Animals ; Cell Line ; Genetic Vectors ; Interferon-gamma ; metabolism ; Mice ; Mice, Knockout ; Recombinant Proteins ; biosynthesis ; Retroviridae ; T-Box Domain Proteins ; biosynthesis ; T-Lymphocytes ; metabolism ; Transfection