OBJECTIVETo establish a food allergy model in Brown Norway (BN) rats by gavage of ovalbumin (OVA) without any adjuvant, and to evaluate this model.

METHODSA total of 20 male BN rats aged 3 weeks were randomly divided into allergy group and control group (n=10 each). BN rats in the allergy group were given OVA 1 mg per day by gavage, and all the rats were treated for 41 days continuously. On day 42, the rats in the allergy group were given OVA 100 mg by gavage for challenge. The rats in the control group were given normal saline of the same volume by gavage. Differences in body length, body weight, and food intake were compared between the two groups on days 7, 14, 21, 28, 35, and 42. ELISA was used to measure the serum OVA-IgE level and plasma histamine level after challenge on day 42, and the changes in rats' appearance and fecal properties were observed. The model of food allergy was considered successful when the serum OVA-IgE level in the allergy group was no less than the mean serum OVA-IgE level + 3 standard deviation in the control group.

RESULTSThere were no significant differences in body length, body weight or food intake between the allergy and control groups at all time points (P>0.05). On day 21, the control group had a significantly higher food intake than the allergy group (P<0.05). On day 42 after challenge, the allergy group showed significantly higher serum OVA-IgE and plasma histamine levels than the control group (P<0.05). The sensitization rate (rate of successful modeling) was 90%. The fecal properties showed no significant differences between the two groups.

CONCLUSIONSOVA by gavage without any adjuvant can successfully establish the model of food allergy in BN rats and has a high success rate. Food allergy induced by OVA may reduce food intake within a short period of time, but no influence on rats' body length or body weight has been observed.

Animals ; Disease Models, Animal ; Food Hypersensitivity ; etiology ; immunology ; Histamine ; blood ; Immunoglobulin E ; blood ; Male ; Ovalbumin ; immunology ; Rats ; Rats, Inbred BN

OBJECTIVETo investigate the synergistic effect of oleanolic acid (OA) and cyclosporine A (CsA) on the survival of renal allografts in rats.

METHODSRenal allograft transplantation was performed using BN rats as donors and LEW rats as recipients. Forty male LEW rats were randomized into 4 equal groups for interventions with DMSO-PBS (control), OA, CsA, or CsA+OA, starting from 1 day before transplantation. Serum creatinine levels were regularly examined, and the survival of rats were recorded. On day 5 after transplantation, CD4(+) and CD8(+) T-cell infiltration in the renal grafts was analyzed by immunohistochemistry; the concentrations of the proinflammatory cytokines (IL-1β, IFN-γ, IL-2, IL-4, and IL-17), anti-inflammatory cytokine IL-10 and chemokines (IP-10, MCP-1, MIP, and Mig) were analyzed with Luminex; the T-cell phenotypes (IFN-γ, IL-10, IL-4, and IL-17) were analyzed using ELISpot.

RESULTSIn OA+CsA group, renal allograft survival was markedly prolonged and CD4(+) and CD8(+) T cell infiltration in the graft significantly decreased as compared to other groups. A significant decrease in IL-2 was observed in OA group and OA+CsA group, especially the latter. Compared with the control group, all the 3 treated groups showed significantly decreased IL-1β, IP-10 and MCP-1, increased IL-10 levels, decreased percentages of T cells secreting IFN-γ, IL-4 and IL-17, and increased percentage of T cells secreting IL-10. The increments of serum IL-10 level and T cell percentage were more prominent in OA+CsA group than in the other two intervention groups.

CONCLUSIONSOA and CsA synergistically ameliorate renal graft rejection and inflammation and promote allograft survival and function in rats.

Animals ; Cyclosporine ; pharmacology ; Cytokines ; metabolism ; Drug Synergism ; Graft Survival ; Kidney ; drug effects ; Kidney Transplantation ; Male ; Oleanolic Acid ; pharmacology ; Rats ; Rats, Inbred BN ; Rats, Inbred Lew ; T-Lymphocytes ; cytology ; Transplantation, Homologous

OBJECTIVETo investigate the mechanism underlying the inhibitory effect of tacrolimus (FK506) against acute liver graft rejection.

METHODSRat models of orthotopic liver transplantation were divided into 3 groups, namely the tolerance group with Brown Norway (BN) rats as the donors and Lewis rats as the recipients, rejection group with Lewis rats as donors and BN rats as recipients, and FK506 group with the same donor-recipient pair as in the rejection group and FK506 treatment. The recipients were sacrificed 7 days after the transplantation, and the hepatic histology, cytokine levels, and glucocorticoid-induced tumor necrosis factor-related protein ligand (GITRL) expression in the liver and Kupffer cells were observed and detected.

RESULTSCompared with the tolerance group, the rejection group showed increased GITRL expressions in the liver and Kupffer cells (P<0.05), which was significantly lowered by FK506 treatment (P<0.05). Acute liver graft rejection caused significantly elevated interferon-γ (IFN-γ) levels and decreased interleukin-10 (IL-10) levels in the plasma and Kupffer cells (P<0.05), and these changes were obviously attenuated by FK506 treatment (P<0.05).

CONCLUSIONThe effect of FK506 in suppressing acute liver graft rejection is probably associated with down-regulated GITRL expression in the liver and Kupffer cells.

Animals ; Carrier Proteins ; metabolism ; Graft Rejection ; prevention & control ; Kupffer Cells ; metabolism ; Liver ; metabolism ; Liver Transplantation ; Male ; Rats ; Rats, Inbred BN ; Rats, Inbred Lew ; Tacrolimus ; pharmacology

Qingkailing injection, Shuanghuanglian injection, baicalin, chlorogenic acid as sample, guinea pig as control, to observe the specificity of allergic response to traditional Chinese medicine (TCM) injection in BN rats and establish a suitable animal model to evaluate applicability of allergic response in BN rats and guinea pigs induced by TCM. BN rats were sensitized by TCM injection, the symptoms, the rate and degree of allergic response were observed, the level of histamine in serum and tissues were determined by ELISA assay, the rate and degree of pathological changes in target organs were observed by HE staining under light microscope. There were significant symptoms of allergic response can be in BN rats, the level of histamine in serum, lung and trachea tissues increased significantly and there were significant pathological changes in lungs and tracheas. Meanwhile, the similar symptoms of allergic response can be induced by penicillin and trichosanthin. The rate and degree of allergic response, the rate and degree of pathological changes was higher in BN rats than in guinea pigs. Compared with guinea pig, BN rat is probably more suitable animal model in evaluating allergic response to injection of TCM.
Animals ; Disease Models, Animal ; Drug Hypersensitivity ; Drugs, Chinese Herbal ; administration & dosage ; adverse effects ; Guinea Pigs ; Hypersensitivity, Immediate ; chemically induced ; Injections ; Male ; Medicine, Chinese Traditional ; Rats ; Rats, Inbred BN

OBJECTIVETo approach the effect of the donor antigenic specificity CD4+CD25+ regulatory T cell (Treg) on cellular immune tolerance function in rat composite tissue allotransplantation (CTA).

METHODSUse the method of immunomagnetic beads to separate CD4+CD25+ Treg, (1 x 10(6))CD4+CD25+ Treg was transfused to rat CTA model. Collected peripheral blood 30 days after operation, and used nylon wool column to separate B cell and T cell. With the stimulation of IgM, detected B cell proliferation and the level of IgG and IgA in serum. Observed the effect of CD4+CD25+ Treg on B cell and T cell function and the survival of allotransplants, and analyzed the data by statistics.

RESULTSThe purity of separated CD4+CD25+ Treg was 95.6%. The CPM of T cell of normal control group, topical intervention group, systemic intervention group and non-intervention group were (2436 +/- 358), (2273 +/- 136), (2338 +/- 228) and (3749 +/- 245). The CPM of B cells of normal control group, topical intervention group, systemic intervention group and non-intervention group were (2418 +/- 348), (2252 +/- 127), (2315 +/- 218) and (3720 +/- 224), there was a significant difference in these groups (P < 0.01). The serum level of IgG and IgA of topical intervention group and systemic intervention group were (12.56 +/- 1.30), (2.38 +/- 0.21), (13.48 +/- 1.23) and (2.86 +/- 0.24) g/L, and of normal control group was (12.35 +/- 1.28), (2.36 +/- 0.12) g/L, had no significant difference (P > 0.05). But Treg of non-intervention group was (16.58 +/- 1.12), (3.75 +/- 0.37) g/L, there was a significant difference in the non-intervention group and the three above groups (P < 0.01). The survival time of CTA in intervention of local and systemic groups were (97 +/- 13) and (63 +/- 10) d, which were significant longer than the non-intervention group [(22 +/- 8) d, P < 0.01].

CONCLUSIONSDonor antigen specific CD4+CD25+ Treg has significantly inhibited B cell and T cell function. It can induce immune tolerance and extend the survival time of CTA; as well local application is better than systemic.

Animals ; B-Lymphocytes ; immunology ; Immune Tolerance ; immunology ; Interleukin-2 Receptor alpha Subunit ; immunology ; Male ; Rats ; Rats, Inbred BN ; Rats, Inbred Lew ; T-Lymphocytes ; immunology ; T-Lymphocytes, Regulatory ; immunology ; Transplantation, Homologous ; immunology

OBJECTIVETo explore the effects of HBsAg pulsed dendritic vaccination on anti-HBs production in immunosuppressed rats after liver transplantation (LT).

METHODSBrown-Norway liver allografts were transplanted into Lewis recipients. The transplanted Lewis rats were injected with EK506 (2 mg/kg) and randomly divided into two groups: rats in HBsAg-DCs group (n = 15) were intraperitoneally injected with HBsAg pulsed DCs at 14 d and 28 d after LT, and rats in the HBsAg group (n = 15) were injected with HBsAg (200 mul) once a week for 12 weeks. Rats without any immunosuppressive treatment after LT served as controls (n = 5). IL-2 and IFN-gamma mRNA expression in spleen were analyzed by RT-PCR, serum IL-2, IFN-gamma and anti-HBs were detected by ELISA.

RESULTSHigh dose of FK506 resulted in the immunosuppressed in LT rats, as evident by low production of IL-2 and IFN-gamma, and without liver rejection compared to rats in the control group. HBsAg-DCs induced high titer of anti-HBs antibody, however, titer of anti-HBs were seldom detectable in the HBsAg group at 1, 2 and 3 mouth after vaccination.

CONCLUSIONThe capacity of HBsAg-DCs to induce anti-HBs in immunosuppressed rats suggested that DC vaccine may prevent HBV recurrence in liver transplanted patients.

Adjuvants, Immunologic ; pharmacology ; Animals ; Cytokines ; blood ; genetics ; metabolism ; Dendritic Cells ; immunology ; Disease Models, Animal ; Hepatitis B ; immunology ; prevention & control ; Hepatitis B Antibodies ; blood ; immunology ; Hepatitis B Surface Antigens ; immunology ; Hepatitis B Vaccines ; Immunosuppression ; Immunosuppressive Agents ; administration & dosage ; Liver Transplantation ; immunology ; Male ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Inbred BN ; Rats, Inbred Lew ; Secondary Prevention ; Spleen ; immunology ; metabolism

Pigment epithelium derived factor (PEDF) has been proven to be an effective drug for the treatment of choroidal neovascularization (CNV). However, the lack of ideal administration route is the biggest bottleneck preventing PEDF from wider clinical use. In this study, we developed a novel PEDF-carrying system which employed immuno-nano-liposomes (INLs) under ultrasound exposure. PEDF-loaded INLs were prepared by conjugating nanoliposomes to the peptide ATWLPPR specifically targeting the receptor-2 for vascular endothelial growth factor (VEGFR-2) and reversely encapsuling PEDF. RF/6A cells were incubated with PEDF-loaded INLs. CNV models of BN rats were injected with PEDF-loaded INLs. MTT assay was used to evaluate the cytotoxicity of the INLs on RF/6A cells. Flow cytometry was conducted to detect the apoptotic rate of cells. Laser scanning confocal microscopy was employed to observe the binding and transmitting process of PEDF-loaded INLs and to calculate the area of CNV in the rat model. The results showed that the PEDF-loaded INLs could exclusively bind to CNV but not to the normal choroidal vessels. The CNV area was significantly decreased in PEDF treatment groups in comparison with control group (P<0.05). Moreover, PEDF-loaded INLs exposed under ultrasound were more efficient in reducing the CNV area (P<0.05). It was concluded that INLs in combination with ultrasonic exposure can transmit PEDF into cytoplasma with high specificity and efficiency, which strengthens the inhibitory effects of PEDF on CNV and reduces its side effects. PEDF-loaded INLs possibly represent a new treatment paradigm for patients with ocular neovascularization.
Animals ; Choroidal Neovascularization ; drug therapy ; Drug Delivery Systems ; Eye Proteins ; therapeutic use ; Female ; Liposomes ; administration & dosage ; Male ; Nanoparticles ; administration & dosage ; Nerve Growth Factors ; therapeutic use ; Peptides ; administration & dosage ; Rats ; Rats, Inbred BN ; Serpins ; therapeutic use ; Ultrasonics ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

PURPOSE: To evaluate the inhibitory effect of chlorogenic acid on laser-induced choroidal neovascularization (CNV) in a rat model. METHODS: Intraperitoneal injection of chlorogenic acid (10 mg/kg) was inititated one day prior to laser photocoagulation and continued for eight days. Eyes were removed 14 days after laser photocoagulation. Fluorescein angiography was employed at seven and 14 days to assess the CNV lesions, and histological examination was performed. Quantification of CNV size and leakage were performed both in histological sections and fluorescein angiography in order to compare the inhibitory effects of chlorogenic acid on CNV with the results of the control. RESULTS: Histological analysis showed no significant difference in CNV size between the treated and control groups. However, CNV leakage on fluorescein angiography had significantly decreased in the chlorogenic acid-treated group at 14 days after laser photocoagulation compared with that of the control group. In addition, CNV size on fluorescein angiography had significantly decreased in the treated group at seven and 14 days. CONCLUSIONS: These results suggest that chlorogenic acid has anti-angiogenic effects on CNV and may be useful as an inhibitor in the treatment or prevention of neovascular age-related macular degeneration.
Angiogenesis Inhibitors/*administration & dosage ; Animals ; Capillary Permeability/drug effects ; Chlorogenic Acid/*administration & dosage ; Choroid/pathology ; Choroidal Neovascularization/diagnosis/etiology/*physiopathology ; Fluorescein Angiography ; Injections, Intraperitoneal ; Laser Coagulation ; Radiation Injuries ; Rats ; Rats, Inbred BN

BACKGROUNDBronchial asthma (BA) and chronic obstructive pulmonary disease (COPD) are both inflammatory airway diseases with different characteristics. However, there are many patients who suffer from both BA and COPD. This study was to evaluate changes of inflammatory airway features and hypothalamic-pituitary-adrenal (HPA) axis function in asthmatic rats combined with COPD.

METHODSBrown Norway (BN) rats were used to model the inflammatory airway diseases of BA, COPD and COPD + BA. These three models were compared and evaluated with respect to clinical symptoms, pulmonary histopathology, airway hyperresponsiveness (AHR), inflammatory cytokines and HPA axis function.

RESULTSThe inflammatory airway features and HPA axis function in rats in the COPD + BA model group were greatly influenced. Rats in this model group showed features of the inflammatory diseases BA and COPD. The expression of inflammatory cytokines in this model group might be up or downregulated when both disease processes are present. The levels of corticotrophin releasing hormone mRNA and corticosterone in this model group were both significantly decreased than those in the control group (P < 0.05).

CONCLUSIONSBN rat can be used as an animal model of COPD + BA. By evaluating this animal model we found that the features of inflammation in rats in this model group seem to be exaggerated. The HPA axis functions in rats in this model group have been disturbed or impaired, which is prominent at the hypothalamic level.

Animals ; Asthma ; immunology ; pathology ; physiopathology ; Corticotropin-Releasing Hormone ; genetics ; Enzyme-Linked Immunosorbent Assay ; Hypothalamo-Hypophyseal System ; pathology ; Inflammation ; physiopathology ; Male ; Pituitary-Adrenal System ; pathology ; Pulmonary Disease, Chronic Obstructive ; immunology ; Rats ; Rats, Inbred BN

BACKGROUNDChoroidal neovascularization (CNV) is a common cause of visual loss in the elderly patients with age-related macular degeneration and represents the growth of subretinal new vessels in the macular region. This study aimed to investigate the relationship between annexin A2 (ANXA2) and vascular endothelial growth factor (VEGF) in CNV.

METHODSIn a rat model of argon laser coagulation-induced CNV, the mRNA expressions of the annexins and VEGF protein expression in the retina were detected using fluorescent real-time polymerase chain reaction (PCR) and immunohistochemistry, respectively. The interactions between ANXA2 and VEGF in both a retinal pigment epithelial cell line RPE-J and the rat model of CNV were examined by means of RNA interference, real-time PCR, Western blotting, enzyme-linked immunosorbent assay (ELISA) and histopathological examinations.

RESULTSFundus fluorescein angiography (FFA) showed that argon laser coagulation of the retina induced stable CNV models in the rats. Two to three weeks after the coagulation, ANXA2 and VEGF expressions in the coagulated area in the retina and choroid increased to the peak level, while the other annexin members (ANXA4, ANXA5, ANXA7 and ANXA11) showed no obvious changes. In RPE-J cells and the CNV model, RNA interference of ANXA2 gene significantly lowered the VEGF protein and mRNA expressions, and application of an adenoviral vector containing ANXA2 gene markedly increased VEGF expressions in the rat model of CNV, but produced no significant effects on the expressions of the kinase insert domain-containing receptor (KDR) or the fms-like tyrosine kinase (Flt-1). The expression of KDR inhibited the increment in ANXA2 expression, but VEGF and Flt-1 did not directly affect ANXA2 expression.

CONCLUSIONBesides the role as a plasminogen and the receptor of tissue plasminogen activator, ANXA2, which is under regulation of KDR via a negative feedback mechanism, also participates in neovascularization by regulating VEGF expression through a positive feedback mechanism.

Animals ; Annexin A2 ; analysis ; genetics ; physiology ; Cells, Cultured ; Choroidal Neovascularization ; etiology ; metabolism ; Disease Models, Animal ; Immunohistochemistry ; Laser Coagulation ; Lasers, Gas ; RNA, Messenger ; analysis ; Rats ; Rats, Inbred BN ; Vascular Endothelial Growth Factor A ; analysis ; genetics ; physiology