Functional expression of B7H1 on pancreatic carcinoma panc-1 cells

AIM: To observe the effect of B7H1 expression in pancreatic carcinoma cells on the proliferation and activation of co-cultured T lymphocytes. METHODS: B7H1 expression in panc-1 cells before and after interferon-γ(IFN-γ) treatment or B7H1-siRNA transfection was evaluated by RT-PCR and flow cytometry. The influence of B7H1 expression on co-cultured PHA-activated T lymphocytes was determined by the methods of MTT and enzyme-linked immunosorbent assay (ELISA). RESULTS: B7H1 was highly expressed in panc-1 cells and up-regulated after IFN-γ stimulation. Such up-regulation led to the significant inhibition of T cell proliferation and secretion of cytokines such as IFN-γ and interleukin-2(IL-2). However, IL-10 production was enhanced. In contrast, knockdown of B7H1 expression in panc-1 cells by RNA interference resulted in increased T cell proliferation as well as IFN-γ and IL-2 production. Meanwhile, the IL-10 secretion decreased. CONCLUSION: B7H1-expressing panc-1 cells suppress T cell function by inhibiting T cell proliferation and production of Th1 cytokines. Suppression of B7H1 expression through siRNA restores T cell immune functions, indicating a potential strategy for immunotherapy against pancreatic cancer.     

Effects of PFOA exposure on inflammatory mediators IL-4, IFN-γ and glucocorticoid receptor in asthmatic mice

AIM: To investigate the effects of perfluorooctanoic acid (PFOA) exposure on the changes of asthmatic mouse airway inflammation, inflammatory mediators interleukin-4 (IL-4) and interferon-γ (IFN-γ) in serum, and glucocorticoid receptor (GR) expression in the lung tissue.METHODS: BALB/c mice (n=30) were randomly divided into 5 groups:normal control (C) group, asthma (A) group, asthma+low-dose PFOA (AP10) group, asthma+ mode-rate-dose PFOA (AP50) group and asthma+high-dose PFOA (AP100) group. Asthma model and PFOA exposure model of mice were established according to the grouping. The animals were sacrificed and their lungs were collected for HE staining, transmission electron microscopy, Western blot and immunohistochemical staining. ELISA was applied to detect the levels of IL-4 and IFN-γ in the serum.RESULTS: HE staining of the lungs showed that the asthmatic mice, compared with the normal control mice, had obvious mucus secretion around the airways and infiltration of inflammatory cells around airways and blood vessels, and the effects were much more marked in AP groups. Ultrastructural alteration of the lung tissues in the asthmatic mice were indicated by transmission electron microscopy. Compared with C group, the results of ELISA in A group and AP groups proved that IL-4 in the serum was increased and IFN-γ was decreased significantly (P<0.05). Compare with A group, IL-4 was significantly increased and IFN-γ was decreased in AP100 group (P<0.05), and no difference of those between AP10 group and AP50 group was found. The results of Western blot indicated that GR protein expression in the asthmatic mice were decreased compare with the normal mice (P<0.05), and no difference of that among A group and AP groups was observed. Immunohistochemical staining manifested that GR protein was mainly located in the cytoplasm of bronchial columnar epithelial cells, airway smooth muscle cells and vascular smooth muscle cells.CONCLUSION: Acute airway PFOA exposure in asthmatic mice dose-dependently exacebates lung inflammation by inducing Th2 type immune responses, promotes infiltration of inflammatory cells and mucus secretion around the airways and blood vessels, and destroys the ultrastructure of the lung tissues.     

Effect of adriamycin combined with sensitized dendritic cells on cervical tumor-bearing mice

AIM：To explore the immunotherapeutic effect of adriamycin (ADM) combined with frozen-thawed antigen-sensitized dendritic cells (DCs) on cervical tumor-bearing mice. METHODS：The U14 cervical cancer model of Kunming mice was established by subcutaneous implantion of U14 cells in axillary fossa. DCs vaccine was prepared by U14 cervical cancer cell frozen-thawed antigen-sensitized mouse bone marrow-derived DCs. Mature phenotype of sensitized DCs was identified by flow cytometry. Tumor-bearing mice were randomly divided into 4 groups and treated for 3 cycles with PBS (control), DCs vaccine, ADM and ADM combined with DCs vaccine, respectively. The tumor volume was evaluated. The tumor weight and the levels of interleukin-2 (IL-2), IL-12 and interferon γ (IFN-γ) in the serum were determined by ELISA on the 21st day. RESULTS：Cancer cell frozen-thawed antigen-sensitized DCs had higher expression levels of CD11C, CD80 and CD86. The volume and weight of the tumor in ADM combined with DCs vaccine group were less than those in ADM group, DCs vaccine group and control group. The tumor inhibitory rate in combination group was higher than that in the other 3 groups. Compared with the other 3 groups, the serum levels of IL-2, IL-12 and IFN-γ in combination group significantly increased. CONCLUSION：ADM combined with tumor antigen-sensitized DCs vaccine can strengthen the animal antitumor immune response and effectively inhibit the growth of tumor in cervical tumor-bearing mice.     

Effects of ginsenoside Rh1 on expression of inflammatory factors in mouse asthma model

AIM: To observe the effects of ginsenoside Rh1 on the levels of inflammatory factors in serum and bronchoalveolar lavage fluid (BALF), and the pathological changes of the lung tissues in an experimentally induced mouse asthma model. METHODS: Male BALB/c mice (n=40) were divided into 4 groups:normal control group, asthma mo-del group, and low-dose (40 mg·kg^-1·d^-1) and high-dose (80 mg·kg^-1·d^-1) ginsenoside Rh1 groups. The bronchial asthma mouse model was established by the method of ovalbumin induction and excitation, and during the excitation period, the mice were daily treated with ginsenoside Rh1 for 2 weeks. At 24 h after the final dose of ginsenoside Rh1, the mice were sacrificed. The number of eosinophils (EOS) and the concentrations of interleukin (IL)-4, IL-5 and interferon (IFN)-γ in BALF were determined. The levels of IgG and IgE in serum were measured, and the expression of transforming growth factor (TGF)-β1 and the pathological changes in lung tissues were evaluated. RESULTS: Ginsenoside Rh1 inhibited the increases in the number of EOS and the concentrations of IL-4, IL-5, IFN-γ and IgE, reversed the increased expression of TGF-β1, and improved the pathological changes of the lung tissues in asthmatic mice. CONCLUSION: Ginsenoside Rh1 improves the immuno-inflammatory profile and pathological changes in the experimentally induced mouse asthma model, implying its potential therapeutic effect on asthma.     

Detection and enrichment of T lymphocytes based on cytokine secretion in human mixed lymphocyte reaction

AIM: Detection and enrichment of T lymphocytes after allogeneic PBMNC stimulation according to secreted cytokine were performed in order to explore a new approach for studying allogeneic reactive T lymphocytes. METHODS: The novel cytokine secretion assay (CKSA) was applied to detect T lymphocyte secreting IFN-γ, IL-4 and IL-10 at single cell level in human mixed lymphocyte reaction. IFN-γ secreting T cells were enriched by means of magnetic sorting system. RESULTS: Allogeneic PBMNC stimulation didn't alter the proportion of IL-4 and IL-10 secreting T lymphocytes (which were 0.12%±0.03% and 0.10%±0.03%, respectively), but increased proportion of IFN-γ secreting T lymphocytes (1.12%±0.13%). These IFN-γ- secreting T lymphocytes could be further enriched to 67.3%±10.5% . CONCLUSION: It is feasible to detect significantly increased IFN-γ-secreting T cells after allogeneic PBMNC stimulation based on the novel CKSA technique, and these cells could be efficiently enriched for further use.     

Expression of IFN-γ, IL-4 and IL-17A in asthmatic mice vaccinated with BCG and HepB in neonatal period

AIM: To investigate the expression of IFN-γ, IL-4 and IL-17A in asthmatic mice vaccinated with bacillus Calmette-Guérin (BCG) and hepatitis B (HepB) in the neonatal period. METHODS: BALB/c mice were randomly divided into BGG+HepB+ovalbumin (OVA) group (B/H/O group), B/O group, H/O group, B/H group, OVA group, BCG group, HepB group and normal saline (NS) group (n=6). The mice in B/H/O group and B/H group at 0, 7 and 14 d received subcutaneous injection of 1×10⁵ CFU BCG for 3 times, while at 0 and 28 d received intramuscular injection of 1.5 μg HepB on the hindlimb twice. The mice in other groups were individually vaccinated with BCG or HepB. OVA sensitization and aerosol inhalation were performed to establish the asthma model. The lung tissues were collected for HE staining. Bronchoalveolar lavage fluid (BALF) and peripheral blood (PB) were collected, and the number of eosinophils (EOS) in BALF was counted. The serum levels of IFN-γ and IL-4, and the level of IL-17A in lung tissue homogenate were measured by ELISA. RESULTS: The pathological changes of the lung in OVA group, B/O group, B/H/O group and H/O group were observed. There were extensive inflammatory cell infiltration around the bronchus, and epithe-lial cell hypertrophy. Those in B/H/O group and H/O group were worse than those in OVA group, while those in B/O group was better than those in OVA group. Total BALF cell counts in B/H/O group, B/O group and H/O group were decreased (P<0.05) as compared with OVA group. The BALF EOS count in B/H/O group was higher than that in B/H group, that in B/O group was higher than that in BCG group, and that in H/O group was higher than that in HepB groups (P<0.05). Compared with H/O group, OVA group and NS group, the serum IFN-γ/IL-4 ratio in HepB group was increased (P<0.05), and compared with B/H/O group, B/O group, OVA group and NS group, that in B/H group was also increased (P<0.05). Compared with OVA group, the level of IL-17A in the lung tissues of B/H/O group and B/O group was decreased (P<0.05), and compared with B/O group, that in B/H/O group was further decreased (P<0.05). CONCLUSION: Combined vaccination of BCG and HepB reduces the inflammotory responses in the lung tissues of asthmatic mice. The mechanism may be related with the decrease in the release of IL-4, the increase in IFN-γ/IL-4, and the inhibition of IL-17A expression.     

The expression of IFN-γ and IL-4 on T lymphocytes that infiltrate in nasal polyps

AIM:To investigate the expression of Th1-typed cytokine IFN-γ and Th2-typed cytokine IL-4 on T lymphocytes that infiltrate in nasal polyps for searching the pathogenesis of nasal polyps. METHODS:Nasal polyps tissue samples and peripheral blood were obtained from 21 patients. Normal human inferior turbinate mucosa and peripheral blood were obtained as well. Flow cytometry was adopted to detect the expression of IFN-γ and IL-4 of T lymphocytes. RESULTS: Th cytokines were rarely detected in inferior turbinate from normal human. Nasal polyps tissue consisted of abundant T lymphocytes. The expression of IL-4 and IFN-γ increased in peripheral blood from patients compared with normal human (P<0.05). The expression of IL-4 increased but the expression of IFN-γ decreased in nasal polyps compared with that of peripheral blood from the same patient (P＜0.05). CONCLUSION:There were generous of T lymphocytes infiltrating in nasal polyps. There was abnormal immune status in the local nasal mucosa from the patients, and the predomination of Th cytokine secretion changed compared with peripheral blood from the same patients, which resulted in the change of microenvironment of nasal mucosa and possibly close related to the formation of nasal polyps.     

Calreticulin expression is necessary for protective immune effect of T-cell vaccine in EAE mice

AIM:To study the role of cell membrane ectopic calreticulin (CALR) expression on the protective immunie effect of T-cell vaccine (TCV) on experimental autoimmune encephalomyelitis (EAE). METHODS:EAE model was established by myelin oligodendrocyte glycoprotein 35-55 (MOG_35-55) immunization in C57BL/6 mice, and the mice were immunized with MOG_35-55-specific CALR⁺ and CALR^- T-lymphocytes. Symptomatic scores were compared at the maximum of the disease. On the 15th day after immunization, the proportion of CD4⁺ CD25⁺ Foxp3⁺ regulatory T cells (Treg) in the spleen, and the expression of interferon-γ (IFN-γ), interleukin-4 (IL-4), IL-10 and IL-17A in the serum were measured. RESULTS:Increased expression of CALR in activated T cells after γ-irradiation was observed. Blockade of CALR on the vaccinating T-cell surface reduced the protective effect of TCV. Furthermore, blockade of CALR reduced the number of Treg in the spleen and up-regulated pro-inflammatory cytokines. CONCLUSION:CALR expression in the T cells is necessary for the protective immunity induced by TCV in EAE mice.     

Influences of protein kinase C inhibitors on the expression of IL-2 and IFN-γ by human T-lymphocytes

AIM:To investigate the influences of protein kinase C(PKC) inhibitors on the expression of interleukin-2(IL-2) and interferon-γ(IFN-γ) byin vitro activated T-lymphocytes. METHODS:Double fluorescent staining together with flow cytometry was adopted to detect intracellular cytokines and to analyze the effects of H7 and gossypol on IL-2 and IFN-γ expression levels of T-lymphocytes stimulated with phorbol ester (PDB)+ionomycin(I) in the presence of monensin.RESULTS:The expression rates of IL-2 and IFN-γ of CD3⁺ T cells stimulated with PDB+I for 4 h were 16.64±2.04 and 25.81±3.53(x±s), respectively, which were significantly higher than that of control (1.06±0.22 and 3.12±0.77)(P＜0.05). Gossypol was able to inhibit the expression of IL-2 and IFN-γ significantly, with the expression rates of 2.08±0.12 and 9.01±1.90, respectively. At the presence of 50 μmol/L H7, the rates of IL-2⁺ and IFN-γ⁺ CD3⁺ T cells were 0.43±0.06 and 2.40±0.27, respectively. The effect of H7 was stronger than that of gossypol. CONCLUSION:PKC plays an important role in the expression of IL-2 and IFN-γ of CD3⁺T cells and its inhibitors H7 and gossypol exert significant inhibitory effect on the expression of these two cytokines. It is suggested that H7 and gossypol may have modulatory effect on T-cell-dependent specific immune responses by inhibiting PKC activity.     

Farnesoid X receptor up-regulates thyrotropin embryonic factor and attenuates pathological injury of Con A-induced hepatitis

AIM：To observe how farnesoid X receptor (FXR) functioned in concanavalin A (Con A) -induced hepatitis (CIH) and the regulation of FXR-thyrotropin embryonic factor (TEF) pathway. METHODS：C57BL/6 mice were injected with Con A to induce hepatitis. The expression of FXR and TEF in the liver specimens was determined by qRT-PCR and Western blotting. The concentrations of serum ALT/AST and inflammatory cytokines IFN-γ, TNF-α, IL-4 and IL-2 in the blood samples were tested after Con A injection. RESULTS：FXR was down-regulated in CIH mice. TEF was up-regulated when FXR was activated by chenodeoxycholic acid (CDCA). Activation of FXR reduced the levels of aminotransferases and inflammatory cytokines IFN-γ, TNF-α, IL-4 and IL-2 in the CIH mice induced by Con A injection. CONCLUSION：FXR activation attenuates CIH mouse liver injury and reduces inflammatory cytokines. FXR activation results in TEF up-regulation. The FXR-TEF pathway may play a protective role in autoimmune hepatitis.     

Specific antitumor immune response induced by pcDNA3.1+/MAGE-3 DNA vaccine in mice

AIM: To construct pcDNA3.1+/MAGE-3 DNA vaccine and investigate the antigen-specific antitumor immune responses induced by pcDNA3.1+/MAGE-3 DNA vaccine in vivo. METHODS: C57BL/6 mice challenged with B16/MAGE-3 cells were immunized by intramuscular injection of pcDNA3.1+/MAGE-3 DNA vaccine every 10 days. pcDNA3.1+ plasmid and PBS were used as controls. After three cycles of immunization, murine splenic lymphocytes, serum, and tumor were obtained for cytotoxity assay, detections of cytokines (IL-2 and IFN-γ), measurement of MAGE-3 antibody, and tumor inhibitory rates, respectively. RESULTS: The pcDNA3.1+/MAGE-3 DNA vaccine immunized murine lymphocytes induced specific cytotoxicity against B16/MAGE-3 cells. Significantly increased secretions of IL-2 and IFN-γ were detected. The titres of antibody against MAGE-3 were 1∶1 and 1∶20, while controls were negative. The tumor inhibitory rate in pcDNA3.1+/MAGE-3 group was significantly different from that in controls. CONCLUSION: The pcDNA3.1+/MAGE-3 DNA vaccine was constructed successfully. pcDNA3.1+/MAGE-3 DNA vaccine activates both cellular and humoral immune responses, and induces antigen-specific antitumor immune responses in vivo.     

The levels of 2′, 5′ oligoadenylate synthetase,interleukin 2 and interleukin 12 in hepatitis B virus infection

AIM: In order to study the effect of endogenous interferon system and Th1 response modes on hepatitis B virus infection, the 2′, 5′ oligoadenylate synthetase (2-5OAS), IL-2 and IL-12 were selected as the research parameters. METHODS: The activity of 2-5OAS in peripheral blood mononeuclear cells was determined by sensitive radioenzymatic assay. IL-2 and IL-12 were determined by ELISA. RESULTS: Compared to normal control, the 2-5OAS, IL-2 or IL-12 were not significantly changed (P>0.05) in the asymptomatic HBsAg carricer group. The 2-5OAS, IL-2 and IL-12 were significantly up-regulated (P<0.01) in the group of acute hepatitis, but in the groups of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, the 2-5OAS, IL-2, IL-12 were significantly down-regulated (P<0.05). Moreover, with the progression of patient′s conditions and with the complications of liver cirrhosis and hepatocellular carcinoma, the 2-5OAS, IL-2 and IL-12 decreased progressively, the 2-5OAS, IL-2, IL-12 were the lowest in guoups of liver cirrhosis and hepatocellular carcinoma (vs each groups of chronic hepatitis, P<0.05). CONCLUSION: The endogenous interferon system and Th1 response are significantly alterable in the different period of hepatitis B virus infection and among the different clinical types. The cellular immunity plays an important role in recovery from HBV infection.     

Effect of microRNA-7 knockdown on ConA-induced acute liver injury in mice

AIM: To study the effect of microRNA-7 (miR-7) knockdown (KD) on concanavalin A (ConA)-induced acute liver injury (ALI) in mice.METHODS: Wild type (WT) mice and miR-7KD mice were received ConA (30 mg/kg) to induced acute liver injury model by intraperitoneal injection, and the morphological changes, liver weight and weight index were measured 48 h later. The pathological changes of the liver tissues were observed by HE staining. The levels of serum alanine aminotransferase (ALT), IL-4 and IFN-γ were detected by ELISA. The proportional changes of CD4⁺ T cells and the relative levels of IL-4 and IFN-γ were analyzed by flow cytometry.RESULTS: The color of the liver tissue became lighter, and the weight and weight index were changed significantly in miR-7KD mice compared with control group (P<0.05). HE staining showed that the inflammatory cell infiltration was increased in the liver of miR-7KD mice. Moreover, the level of serum ALT was significantly increased (P<0.05). The serum level of IFN-γ elevated significantly (P<0.01), while the IL-4 levels decreased significantly (P<0.01) in the serum of miR-7KD mice. Furthermore, the proportion of CD4⁺ T cells and relative IFN-γ cells increased obviously (P<0.01).CONCLUSION: miR-7 knockdown promotes the pathogenesis of the ConA-induced acute liver injury in mice.     

Design and immune activity detection of long peptide vaccines targeting lung cancer antigen COX-2

AIM:To design long peptides based on cytotoxic T-lymphocytes (CTL) epitope prediction for lung cancer antigen cyclo-oxygenase-2 (COX-2) and to study the immune activity of the long peptides. METHODS:HLA-A2 epitopes from COX-2 protein were predicted by NetCTL 1.2, SYFPEITHI and IEDB. The CTL epitope-concentrated area was analyzed, and the appropriate length of long peptides were designed. In vitro activity experiments were used to verify the immune activity of the long peptides. ELISPOT assay and intracellular cytokine staining assay were used to investigate the ability of the peptide to induce specific restricted CTLs and release of interferon-γ (IFN-γ). The ability of the peptides to induce T-cell response was investigated by lactate dehydrogenase (LDH) and CFSE cytotoxicity assay in vitro. RESULTS:ELISPOT and intracellular cytokine staining assay showed P315-338 and P375-401 were able to induce specific CTLs and higher levels of IFN-γ release. The results of LDH and CFSE cytotoxicity assays showed the CTLs induced by P315-338 and P375-401 lysed the target cells. CONCLUSION:Two long peptides pointing to lung cancer antigen COX-2 are successfully identified, which could be used as immunotherapy vaccine in future.     

Effect of hepatitis virus B protein on the functions of PBMCs isolated from patients with chronic HBV infection

AIM: To study the effect of hepatitis virus B proteins on peripheral blood mononuclear cells (PBMCs) from patients among various types of chronic hepatitis B virus (HBV) infection.METHODS: 80 patients of various types of chronic HBV infection were observed, including 40 HBeAg positive with abnormal alanine aminotransferase (ALT) (A group), 20 HBeAg positive with persistent normal ALT(B group), 20 HBeAg and HBV-DNA negative with persistent normal ALT level(C group). IL-10, IFN-γ in CD8+CD28+T cells, after stimulation with PHA, HBeAg and HBcAg for 48 h, were inspected respectively in PBMCs.RESULTS: IFN-γ was significantly lower in HBeAg positive patients. IL-10 was significantly higher in HBeAg positive with normal ALT. CD8+CD28+T were significantly lower than others. CONCLUSION: In HBeAg positive group, secretion of cytotoxic T lymphocyte (CTL) and Th1 type cellular immunologic reaction is decreased, Th2 type cellular immunologic reaction is enhanced.     

Effect of 1α, 25-dihydroxyvitamin D3 on T helper cell 17 and expression of related cytokines in penetrating keratoplasty in mice

AIM: To evaluate the effects of 1α, 25-dihydroxyvitamin D3 on T helper cell 17 (Th17 cells) and its related cytokines in a mouse model of corneal allograft transplantation. METHODS: C57BL/6 mice were transplanted with corneal grafts from BALB/c mice and treated intraperitoneally with 1.0 μg 1α, 25-dihydroxyvitamin D3 or soybean oil every other day after operation. The transparency of the corneal grafts was evaluated for potential rejection signs by slit lamp biomicroscopy and histopathology. The expression levels of IL-17, RORγt and IFN-γ in the spleen were measured by real-time PCR. Moreover, the protein expression of RORγt and IL-17 in the peripheral blood was analyzed by Western blotting. IL-17 and IFN-γ in peripheral blood were measured by flow cytometry. RESULTS: 1α, 25-dihydroxyvitamin D3 significantly inhibited the rejection of the corneal allograft and reduced the numbers of inflammatory infiltrates in the corneal graft. In the spleen, 1α, 25-dihydroxyvitamin D3 treatment reduced the expression levels of IL-17, RORγt and IFN-γ. In the peripheral blood, 1α, 25-dihydroxyvitamin D3 treatment downregulated the expression levels of RORγt, IL-17 and IFN-γ. CONCLUSION: The effects of 1α, 25-dihydroxyvitamin D3 on suppressing corneal transplantation-induced allograft rejection in mice are closely associated with its modulation on IL-17 and related cytokine RORγt.     

Effects of arsenic trioxide on T-bet/GATA3 signal pathway in MRL/lpr mice

AIM: To investigate the effect of arsenic trioxide (ATO) on T-bet/GATA3 signal pathway in MRL/lpr mice.METHODS: MRL/lpr mice and C57BL/6J mice at the age of 20 weeks were chosen and then divided in 2 different sub-groups, respectively. The mice in 2 sub-groups received ATO (0.4 mg·kg^-1·d^-1) and sodium chloride (NS, volume weight-determined) by intraperitoneal injection respectively for 2 months. Afterward, the spleens were isolated from the MRL/lpr and C57BL/6J mice under pathogen-free condition and the suspensions were prepared. The mRNA level of T-bet, GATA3, IFN-γ,IL-4 and the mRNA ratio of T-bet/GATA3 were detected by RT-qPCR. The protein expression of T-bet and GATA3 was determined by Western blot. The serum levels of IFN-γ and IL-4 were measured by ELISA.RESULTS: The mRNA and protein levels of T-bet, IFN-γ and the mRNA ratio of T-bet/GATA3 in NS group of MRL/lpr mice were higher than those in NS group of C57BL/6J mice (P<0.05). However, the GATA3 and IL-4 were lower in NS group of MRL/lpr mice in both mRNA and protein level (P<0.05). In MRL/lpr mice, the mRNA and protein levels of T-bet, IFN-γ and the mRNA ratio of T-bet/GATA3 were lower in ATO group compared with NS group (P<0.05), no difference was found in GATA3 and IL-4. No difference of the indexes mentioned above between ATO group and NS group in C57BL/6J mice was observed.CONCLUSION: ATO may affect the signaling pathway of T-bet/GATA3 to down-regulate the mRNA expression and the protein secretion of IFN-γ by decreasing the expression of T-bet in MRL/lpr mice.     

Anti-tumor efficacy and immune mechanism of gene vaccine expressing PSMA

AIM: To observe both the anti-tumor efficacy induced by gene vaccine expressing PSMA in mice and the feather of the specific immune responses, which may offer some theoretical knowledge and experimental foundation of the gene vaccine therapy for the prostate cancer.METHODS: pcDNA3.0-PSMA plasmids were injected into the hind-leg quadriceps muscle of the BALB/c mice. Anti-PSMA antibody was detected in sera of the animals. The proliferation and cytotoxicity of the spleen cells were observed. The immunized mice were inoculated subcutaneously in the right flank with sp2/0-PSMA cells. The anti-tumor efficacy of the gene vaccine was determined through the ratio of the tumor formation, tumor volume, tumor weight and the survival rate of immunized mice.RESULTS: High levels of anti-PSMA antibody were induced in the immunized mice. The splenocytes from vaccination group were stimulated to produce strong proliferative responses and significant cytotoxic T-cells (CTL) activity. Moreover, during a period of time, the antibody concentration, proliferation index and CTL activity appeared to go up as the time went by and the numbers of immunization increased. After DNA vaccine immunization, tumor occurrence decreased, the tumor-free time was prolonged and the growth velocity of tumor was markedly reduced (P<0.05).CONCLUSION: The humoral and cellular immunity is induced by PSMA gene vaccine. The anti-tumor efficacy in the immunized mice is produced strikingly.     

Suppressive effect of interferon γ on IL-13-induced fibrosis in fibroblasts

AIM：To investigate the suppressive effect of interferon γ (IFN-γ) on fibrosis induced by interleukin 13 (IL-13) in fibroblasts. METHODS：The fibroblasts were divided into IFN-γ (4×105U/L) group, IL-13 (100 μg/L) group, IFN-γ+IL-13 group and blank control group. At 24 h, 48 h and 72 h, the secreted collagen from fibroblasts was measured by hydroxyproline release assay. The mRNA expression of collagen type I α1 (Col1A1) in fibroblasts was examined by RT-PCR. The protein level of collagen type I synthesized in fibroblasts was analyzed by Western blotting. RESULTS：IFN-γ at 4×105U/ L significantly inhibited the proliferation of fibroblasts and down-regulated Col1A1 mRNA and cellular collagen. The mRNA expression of Col1A1 and the protein level of collagen type I in IFN-γ group were lower than those in blank control group at 48 h and 72 h. At 72 h, the mRNA expression of Col1A1 and the protein level of collagen type I in IL-13 group were substantially higher than those in blank control group, those in IFN-γ + IL-13 group were remarkable lower than those in blank control group, and those in IFN-γ group were also lower than those in blank control group. CONCLUSION：IFN-γ inhibits the fibrotic effect of IL-13 in fibroblasts.