Objective To investigate the effects of inhaled prostaglandin E1 （PGE1）on Th1/Th2 polarity in rat model of lipopolysaccharide（LPS） induced acute lung injury（ALI）.Methods Healthy adult male Wistar rats [weight （200±20）g] were randomly divided into normal control（NS） group，LPS group and PGE1 group.The model of ALI were established by injecting LPS of 5 mg/kg into caudal vein.The rats in PGE1 group inhaled aerosolized PGE1（2 μg/mL）for 30 minutes after LPS injection,then repeat the procedure 12 hours later. 1 h，6 h，12 h and 24 h after last PGE1 inhalation,enzyme linked immunosorbant assay （ELISA） was empolyed to measure the level of interferon-γ（IFN-γ）and interleukin-4（IL-4）in the serum and bronchoalveolar lavage fluid（BALF）and the ratio of IFN-γ/IL-4（Th1/Th2）was calculated.Pathological examination was made under light microscope.Results Pathological examination of lung tissue demonstrated success ALI model.Compared to NS group,the ratio of IFN-γ/IL-4（Th1/Th2）both in serum and BALF in LPS group elevated significantly（Plt;0.01）. PGE1 administration significantly decreased the ratio IFN-γ/IL-4 in serum after 6h（Plt;0.01）and in BALF at all time points（Plt;0.01）.Conclusion The imbalance of was found in the LPS induced ALI，inhaled PGE1 aerosol inhalation could restore Th1/Th2 cytokine balance in the rats model induced by LPS.
Objective To explore immunosuppressive effect and sappan L （WECSL） in heart transplantation of rats. Methods mechanism of watery extract of caesalppinia Wistar rats （donor） heart allografts were transplanted into the abdomen of SD rats （receptor）. Ninety-six SD rats were divided into four groups （24 rats in each group）. Control group： olive oil（8ml/kg·d） treated; group A： cyclosporine A （CsA,5ml/kg·d） treated; groupB： WECSL（37.5g/kg·d） treated; group C： WECSL（25g/kg·d） plus semidose of CsA（2.5mg/kg·d） treated. Median survival time of heart allografts and the histological changes of allografts were examined. Messenger ribonucleic acid （mRNA） of interleukin-2（IL-2）, interleukinf-10（IL-10） in the myocardium were determined by reverse transcription polymerase chain reaction （RT-PCR）, serum level of IL-2 and IL-10 were determined by enzyme-linked immunosorbent assay （ELISA） at 3, 7 days after surgery. Results Compared with control group, median survival time of heart allografts in group A, group B, group C was prolonged （P〈0. 01）, lymphocyte infiltration and myocyte necrosis were relieved, mRNA expression of IL-2 in allografts was lower, mRNA expression of IL-10 was higher （P〈0.01）. The serum levels of IL-2 in group A 3,7days after surgery and in group B, group C 3 days after surgery was lower than that in control group （P〈0.01）. The serum levels of IL-10 in group A 7days after surgery and in group B 3 days after surgery was higher than that in control group （P〈0. 05）. Conclusion Acute rejection of rat heart transplantation can be effectively suppressed by WECSL, Th1 to Th2 polarization induced by WECSL is observed.
Objective To study the relationship between Th1/Th2 cytokines messenger ribonucleic acid (mRNA) expression and immune tolerance to cardiac allografts in rats. Methods Male DA rat hearts were transplanted to male Lewis rats using Ono’s model and randomly divided into three groups: control group, rejection group, and tolerance group (each group 10 rats). Mean survival time (MST), histological changes, mRNA expression level of Th1/Th2 cytokines interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-4(IL-4), interleukin-10(IL-10) were measured. Results MST (85.28±7.48 d) of heart allografts in tolerance group was significantly longer than that(7.33±1.03 d) in rejection group. Only a few inflammatory cells infiltrated in cardiac allografts in tolerance group. The mRNA expression of IL-2, IFN-γ (Th1 cytokines) in rejection group were much ber than those in control group, and in tolerance group were much lower; mRNA expression of IL-4, IL-10 (Th2 cytokines) in rejection group were much ...更多lower than those in control group,and in tolerance group were much ber than those in control group. Conclusions The dynamic equilibrium of Th1/Th2 cytokines is very important in immune tolerance. The deviation of Th1 to Th2 is one of the mechanisms in immune tolerance.
Objective To investigate the expression and significance of T-bet in experimental autoimmune uveoretinitis (EAU). Methods EAU was induced in 24 Lewis rats by immunization with retinal S-antigen (50 μg) and complete Freund′s adjuvant, and another 4 rats were the healthy control. The rats with EAU were executed 7, 12, 15, 21 days after immunization, respectively. Immunohistochemical single and double staining were performed using monoclonal antibodies of T-bet or CD4 on the ocular wholemounts and the consecutive sections of the eye and spleen from both 24 immunized Lewis rats and 4 normal controls. The positive cells were counted under the optic microscope and the data were analyzed by SPSS 11.0 statistic software. Results A few T-bet positive cells were observed in the normal ocular tissues and spleen. The expressions of T-bet in the iris, retina, and spleen increased 7 days after immunization, reached the peak at the 15th day, and decreased at the 21st day, which were higher than those in the control. Double staining on the consecutive sections revealed that most of the T-bet positive cells were positive for CD4 monoclona l antibody. Conclusion T-bet may affect the occurrence of EAU by activating Th1 cells. (Chin J Ocul Fundus Dis，2004，20：172-174)
ObjectiveTo observe whether interleukin-27 (IL-27) intervention could diminish allergic airway inflammation of mouse asthma induced by ovalbumin (OVA) and to investigate the related molecular mechanisms. MethodsSixty female C57/6J mice were randomly divided into six groups, a control group, an asthma group, two IL-27 prevention groups and two IL-27 treatment groups. Based on being sensitized and challenged with OVA in the asthma model, two kinds of IL-27 intervention asthma models were set up, one of which was low-dose multiple prevention model, the other was high-dose few times treatment model. HE stain and inflammation score were done for the lungs. CD4+ T cells were purified from mice spleen and cultured under Th2 medium with/without IL-27. Interleukin-4 (IL-4) was measured by ELISA. CD4+ T cells were cultured under different stringent Th2 medium and stimulated by IL-27. The level of total signal transducer and activator of transcription-1 (STAT1) protein and phos-STAT1 were tested by Western blot. ResultsIn low-dose multiple prevention group, IL-27 inhibited inflammation around bronchial and vascular obviously, the inflammation score was lower than the asthma group (P < 0.05), while the treatment group had no obvious statistical significance (P > 0.05). IL-27 repressed Th2 differentiation of naïve CD4+ T cells which was independent of interferon-γand IL-10. This effect was via STAT1 signaling pathway. CD4+ T cells from asthma mice or cultured under high-IL-4 inducing medium were found impairment of STAT1 phosphorylation. ConclusionsIL-27 could inhibit Th2 differentiation of naïve CD4+ T cells, but not in already committed Th2-CD4+ T cells. The inhibition effect of IL-27 for airway inflammation is obvious in prevention group, while the treatment group shows obviously resistance to inhibitory effect of IL-27. Already committed Th2-CD4+ T cells existed in asthma airway might be the reason for IL-27 resistance.
Objective Respiratory syncytial virus ( RSV) is a primary cause of lower respiratory tract infections in children, and is also the cause for the development of asthma primarily in infants. However,the immunological mechanisms by which RSV enhances allergic sensitization and asthma remain unclear. The aimof this study was to examine the influence of RSV-infected airway epithelial cells on the activation and functions of rat myeloid dendritic cells ( mDCs) . Methods Rat airway epithelial cells ( RAECs) were infected by RSV. Then RSV-infected RAECs were co-cultured with rat mDCs, and the expression of cytokine and maturation markers on mDCs were examined by real time PCR and flow cytometry. To confirm this functional mDC maturation, allergenic mixed lymphocyte reaction ( MLR) were performed. Results Wefound that functional maturation of mDCs was induced by RSV-treated RAECs, as shown by their enhanced levels of OX40L and thymus- and activation-regulated chemokine ( TARC) mRNAs, which increased the expressions of major histocompatibility complex II ( MHCII) and CD86 costimulatorymolecules and promotedT-cell proliferation in mixed lymphocyte reactions. Conclusion Our results suggest that RSV-infected epithelial cells promote the maturation of mDCs that might support Th2 cell polarization and contribute to the pathogenesis of asthma.