BACKGROUNDAllergic asthma is a chronic airway inflammatory disease partly characterised by high concentration of T help 2 (Th2) cytokines in bronchoalveolar lavage fluid (BALF). There is no report on the relation of peripherally circulating blood lymphocytes and asthma. We explored the balance of Th2/Th1 cytokines in asthmatic mice. Exogenous recombinant interleukin (IL) 33 acted on murine peripheral circulating blood lymphocytes, IL-5 cytokine was selected for assessing Th2 cytokines and interferon-gamma (IFN-γ) for Th1 cytokines.

METHODSFemale specific pathogen free BABL/c mice were sensitised by intraperitoneal injection of 20 µg of ovalbumin emulsified in 1 mg of aluminium hydroxide gel in a total volume of 200 µl, and challenged for 30 minutes in 7 consecutive days with an aerosol of 2 g ovalbumin in 100 ml of PBS. Then we collected BALF and isolated lymphocytes from the peripheral blood. The lymphocytes were divided into two groups: asthmatic group and normal group. Th1/Th2 cytokines was detected by enzyme-linked immunosorbent assay (ELISA) kits.

RESULTSIn the asthma group, we found numerous eosinophils and lymphocytes on the glass slides. We then confirmed that the optimal concentration of IL-33 was 10 ng/ml and time of IL-33 stimulating lymphocytes was 24 hours. In the asthma group, the production of IL-5 was significantly increased over normal group after stimulation with IL-33 (P < 0.05) and the production of IFNγ was supressed from IL-33 stimulated lymphocytes (P < 0.05).

CONCLUSIONIL-33 acts on lymphocytes of peripheral blood increasing secretion of Th2 cytokines and inhibiting secretion of Th1 cytokines.

Animals ; Asthma ; chemically induced ; immunology ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Female ; Interferon-gamma ; immunology ; metabolism ; Interleukin-33 ; Interleukin-5 ; immunology ; metabolism ; Interleukins ; immunology ; metabolism ; Lymphocytes ; immunology ; metabolism ; Mice ; Mice, Inbred BALB C

PURPOSE: Cockroach (CR) is an important inhalant allergen and can induce allergic asthma. However, the mechanism by which CR induces airway allergic inflammation and the role of endotoxin in CR extract are not clearly understood in regards to the development of airway inflammation. In this study, we evaluated whether endotoxin is essential to the development of CR induced airway allergic inflammation in mice. MATERIALS AND METHODS: Airway allergic inflammation was induced by intranasal administration of either CR extract, CR with additional endotoxin, or endotoxin depleted CR extract, respectively, in BALB/c wild type mice. CR induced inflammation was also evaluated with toll like receptor-4 (TLR-4) mutant (C3H/HeJ) and wild type (C3H/HeN) mice. RESULTS: Intranasal administration of CR extracts significantly induced airway hyperresponsiveness (AHR), eosinophilic and neutrophilic airway inflammation, as well as goblet cell hyperplasia in a dose-dependent manner. The addition of endotoxin along with CR allergen attenuated eosinophilic inflammation, interleukin (IL)-13 level, and goblet cell hyperplasia of respiratory epithelium; however, it did not affect the development of AHR. Endotoxin depletion in CR extract did not attenuate eosinophilic inflammation and lymphocytosis in BAL fluid, AHR and IL-13 expression in the lungs compared to CR alone. The attenuation of AHR, eosinophilic inflammation, and goblet cell hyperplasia induced by CR extract alone was not different between TLR-4 mutant and the wild type mice. In addition, heat inactivated CR extract administration induced attenuated AHR and eosinophilic inflammation. CONCLUSION: Endotoxin in CR extracts may not be essential to the development of airway inflammation.
Allergens/*immunology ; Animals ; Asthma/*chemically induced/*immunology/metabolism ; Cockroaches/*immunology ; Endotoxins/*immunology ; Enzyme-Linked Immunosorbent Assay ; Female ; Inflammation/*chemically induced/*immunology/metabolism ; Interferon-gamma/metabolism ; Interleukin-13/metabolism ; Interleukin-5/metabolism ; Mice ; Mice, Inbred BALB C ; Respiratory Hypersensitivity/chemically induced/*immunology

To determine the impact of IL-23 knockdown by RNA interference on the development and severity of ovalbumin (OVA)-induced asthmatic inflammation, and the potential mechanisms in mice, the IL-23-specific RNAi-expressing pSRZsi-IL-23p19 plasmid was constructed and inhaled into OVA-sensitized mice before each challenge, as compared with that of control mice treated with alum or budesonide. Inhalation of the pSRZsi-IL-23p19, significantly reduced the levels of OVA-challenge induced IL-23 in the lung tissues by nearly 75%, determined by RT-PCR. In addition, knockdown of IL-23 expression dramatically reduced the numbers of eosinophils and neutrophils in BALF and mitigated inflammation in the lungs of asthmatic mice. Furthermore, knockdown of IL-23 expression significantly decreased the levels of serum IgE, IL-23, IL-17, and IL-4, but not IFNgamma, and its anti-inflammatory effects were similar to or better than that of treatment with budesonide in asthmatic mice. Our data support the notion that IL-23 and associated Th17 responses contribute to the pathogenic process of bronchial asthma. Knockdown of IL-23 by RNAi effectively inhibits asthmatic inflammation, which is associated with mitigating the production of IL-17 and IL-4 in asthmatic mice.
Animals ; Asthma/chemically induced/genetics/metabolism/*prevention & control ; Bronchoalveolar Lavage Fluid/cytology ; Enzyme-Linked Immunosorbent Assay ; Eosinophils ; Female ; Inflammation/metabolism ; Interleukin-23/*genetics ; Leukocyte Count ; Mice ; Mice, Inbred BALB C ; Neutrophils ; Ovalbumin/pharmacology ; Plasmids/genetics ; *RNA Interference ; RNA, Small Interfering/*genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Th17 Cells/immunology

OBJECTIVETo investigate the effect of prostaglandin D2 receptor antagonists on the airway inflammation in rats with asthma.

METHODSForty male SD rats were randomly divided into four groups: Group A (normal control), Group B (asthma group), Group C (CRTH2 antagonist BAYu3405 treatment group), Group D (DP1 antagonist BWA868C treatment group). Asthma was induced by ovalbumin (OVA) challenge. The rats in each group were sacrificed 24 h after the last challenge of OVA.DP1/CRTH2 receptors on eosinophils (EOS) were measured by radiological binding assay (RBA). The left lungs were used for histological examinations and bronchoalveolar lavage fluid (BALF) was collected from the right lungs. The total cell numbers, EOS absolute count and differential cell counts in BALF were performed. Serum concentrations of IL-4, 5 and IFN-gamma were measured by ELISA.

RESULTSRats in BAYu3405 treatment group showed profoundly decreased infiltrates of EOS and lymphocytes in the wall of bronchus when compared with those of asthma group and BWA868C treatment group. Serum concentrations of IFN-gamma in rats of BAYu3405 treatment group increased, but IL-4 and IL-5 decreased significantly when compared with those in rats of asthma group and BWA868C treatment group (P<0.01), and BALF EOS count was decreased significantly (P<0.01). Peripheral blood EOS count was higher than that in rats of normal control group, but was not significantly different from that in rats of asthma group and BWA868C treatment group. The combining capacity of CRTH2 and DP total combining capacity on EOS in asthma group, BAYu3405 treatment group and BWA868C treatment group were significantly higher than those in Group A (P<0.01). There was no significant difference in DP1 among all the groups (P>0.05).

CONCLUSIONCRTH2, but not DP1 antagonist can effectively ameliorate airway inflammation in rats with asthma.

Animals ; Asthma ; chemically induced ; drug therapy ; pathology ; Bronchi ; immunology ; pathology ; Carbazoles ; pharmacology ; therapeutic use ; Inflammation ; drug therapy ; Male ; Ovalbumin ; Prostaglandin D2 ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Immunologic ; antagonists & inhibitors ; Receptors, Prostaglandin ; antagonists & inhibitors ; Sulfonamides ; pharmacology ; therapeutic use

BACKGROUNDDisequilibrium of Th1/Th2 is known as an important cause of allergic asthma with a biased Th2 type response. It has been shown that lipopolysaccharide (LPS) administration during post-sensitization modified the inflammation of asthma via upregulating the Th1 response that decrease the Th2 immunity. We would like to know if, during pre-sensitization, the elevated Th1 response is necessary for LPS exposure to modify the asthmatic response.

METHODSDuring pre- or post-sensitization, 40 microg LPS were intraperitoneal injected (i.p.) to asthmatic mice sensitized and challenged by Dermatophagoides farinae (D. farinea). Inflammation was assessed by examining bronchoalveolar lavage fluid (BALF) for the number and identity of cells and by cytokine titers measured by ELISA. Semi-quantified RT-PCR was used to evaluate the level of Toll-like receptor 4 (TLR4) mRNA in dendritic cells (DCs) from bone marrow (BMDCs).

RESULTSThese investigations demonstrated that LPS exposure during pre-sensitization inhibited the Th2 cytokine and inflammatory infiltration, the same as with LPS exposure during post-sensitization in allergic asthma mice. Contrary to post-sensitization LPS exposure, the Th1 cytokines were not upregulated by pre-sensitization with LPS. Finally, the study failed to show any significant difference between TLR4 mRNA expressed in BMDCs with the two times of LPS exposure.

CONCLUSIONSOur data suggest that elevated Th1 immunity is not required for the modification of the Th2 response induced by LPS exposure during pre-sensitization in asthmatic mice and that pre-sensitization differs from post-sensitization. Immune modulation with treatment is independent of TLR4 expression in BMDCs. This study implicates a potential way to protect from allergic disease and an inflammatory response.

Animals ; Asthma ; chemically induced ; immunology ; Bronchoalveolar Lavage Fluid ; immunology ; Cytokines ; immunology ; metabolism ; Dendritic Cells ; immunology ; Dermatophagoides farinae ; immunology ; Female ; Lipopolysaccharides ; immunology ; Mice ; Mice, Inbred BALB C ; Reverse Transcriptase Polymerase Chain Reaction ; Th1 Cells ; immunology ; Th2 Cells ; immunology ; Toll-Like Receptor 4 ; genetics

OBJECTIVETo study the effects of dexamethasone on intracellular expression of Th17 cytokine interleukin 17 and the mechanisms in asthmatic mice.

METHODSExperimental asthma was induced by ovalbumin (OVA) sensitization in 20 in female Balb/c mice with (dexamethasone group, n=10) or without dexamethasone treatment (model group, n=10), with another 10 serving as the control group. The levels of IL-17 in the bronchoalveolar lavage fluid (BALF) and serum of the mice were measured by enzyme-linked immunosorbent assay (ELISA), and the airway inflammation was evaluated by HE staining. The expressions of IL-17 and RORgammat mRNA were measured by reverse transcription-polymerase chain reaction (RT-PCR), and the expression of RORgammat protein was measured by immunohistochemical staining.

RESULTSThe levels of RORgammat and IL-17 mRNA and protein in the asthmatic model group were significantly higher than those in the control group (P<0.01), and the increased expressions of RORgammat and IL-17 mRNA and protein in the asthmatic mice were significantly reduced by dexamethasone treatment (P<0.05).

CONCLUSIONDexamethasone can inhibit the release of IL-17 probably by inhibiting RORgammat expression and blocking Th17 differentiation in asthmatic mice.

Animals ; Asthma ; chemically induced ; immunology ; metabolism ; Dexamethasone ; pharmacology ; Female ; Interleukin-17 ; genetics ; metabolism ; Mice ; Mice, Inbred BALB C ; Nuclear Receptor Subfamily 1, Group F, Member 3 ; metabolism ; Ovalbumin ; RNA, Messenger ; biosynthesis ; genetics ; T-Lymphocyte Subsets ; immunology ; metabolism ; T-Lymphocytes, Helper-Inducer ; immunology ; metabolism

BACKGROUNDTyrosine kinase signaling cascades play a critical role in the pathogenesis of allergic airway inflammation. Sunitinib, a multitargeted receptor tyrosine kinase inhibitor, has been reported to exert potent immunoregulatory, anti-inflammatory and anti-fibrosis effects. We investigated whether sunitinib could suppress the progression of airway inflammation, airway hyperresponsiveness (AHR), and airway remodeling in a murine model of chronic asthma.

METHODSOvalbumin (OVA)-sensitized mice were chronically challenged with aerosolized OVA for 8 weeks. Some mice were intragastrically administered with sunitinib (40 mg/kg) daily during the period of OVA challenge. Twelve hours after the last OVA challenge, mice were evaluated for the development of airway inflammation, AHR and airway remodeling. The levels of total serum immunoglobulin E (IgE) and Th2 cytokines (interleukin (IL)-4 and IL-13) in bronchoalveolar lavage fluid (BALF) were measured by ELISA. The expression of phosphorylated c-kit protein in the lungs was detected by immunoprecipitation/Western blotting (IP/WB) analysis.

RESULTSSunitinib significantly inhibited eosinophilic airway inflammation, persistent AHR and airway remodeling in chronic experimental asthma. It reduced levels of total serum IgE and BALF Th2 cytokines and also lowered the expression of phosphorylated c-kit protein in remodelled airways.

CONCLUSIONSSunitinib may inhibit the development of airway inflammation, AHR and airway remodeling. It is potentially beneficial to the prevention or treatment of asthma.

Angiogenesis Inhibitors ; pharmacology ; Animals ; Asthma ; chemically induced ; drug therapy ; immunology ; Blotting, Western ; Bronchial Hyperreactivity ; chemically induced ; immunology ; Bronchoalveolar Lavage Fluid ; chemistry ; Female ; Immunoglobulin E ; blood ; Immunohistochemistry ; Immunoprecipitation ; In Vitro Techniques ; Indoles ; pharmacology ; Inflammation ; chemically induced ; immunology ; Interleukin-13 ; metabolism ; Interleukin-4 ; metabolism ; Lung ; drug effects ; immunology ; metabolism ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; pharmacology ; Proto-Oncogene Proteins c-kit ; metabolism ; Pyrroles ; pharmacology

Asthma was induced by the sensitization and challenge with ovalbumin (OVA) in mice. B-cell activating factor (BAFF) plays a role in mature B cell generation and maintenance. Here, we investigated whether, BAFF expression was changed in OVA-induced mice and whether the control of BAFF expression level alleviates the symptom of bronchial asthma. BAFF expression was detected in alveolar-associated cells surrounding bronchi of OVA-induced mouse lung tissues. BAFF protein was also increased in OVA-induced mouse serum. The increased BAFF transcripts was detected in OVA-induced mouse splenocytes. OVA-induced asthma was associated with the increased number of eosinophils in bronchoalveolar lavage fluid (BALF). When TACI:Fc scavenging soluble BAFF was injected to OVA-induced mice, a significant inhibition was detected in the thickness of airway smooth muscle and glycol-containing cellular elements in airway that were visualized by hematoxylin/eosin Y and periodic acid-Schiff staining, respectively. In addition, when mice were treated with TACI:Fc protein, BAFF protein level was decreased in alveolar-associated cells surrounding bronchi of OVA-induced mouse lung tissues compared to control mice. When compared to OVA-induced control, TACI:Fc treatment reduced the percentage of non-lymphoid cells and no changes were detected in lymphoid cell population. Hypodiploid cell formation in BALF was decreased by OVA-challenge but it was recovered by TACI:Fc treatment. Collectively, data suggest that asthmatic symptom could be alleviated by scavenging BAFF and then BAFF could be a novel target for the develpoment of anti-asthmatic agents.
Animals ; Apoptosis ; Asthma/chemically induced/*drug therapy/immunology ; B-Cell Activating Factor/*biosynthesis ; Bronchi/metabolism/pathology ; Bronchoalveolar Lavage Fluid/cytology ; Eosinophils/pathology ; Female ; Humans ; Immunoglobulin Fc Fragments/*genetics ; Immunoglobulin G/*genetics ; Lymphocytes/pathology ; Mice ; Mice, Inbred BALB C ; *Ovalbumin ; Pulmonary Alveoli/metabolism ; Recombinant Fusion Proteins/genetics/*therapeutic use ; Spleen/metabolism ; Transmembrane Activator and CAML Interactor Protein/*genetics

OBJECTIVE: To explore the effect of Th1/Th2 cytokines on the expression of nerve growth factor(NGF)in splenic lymphocytes in asthmatic model. METHODS: Four SD rats were sensitized and challenged with ovalbumin to establish an asthmatic model, and the rat splenic lymphocytes were isolated and cultured with ConA. The expressions of NGF mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR), and were observed after the lymphocytes were exogenously added with interferon-gamma(IFN-gamma) or interleukin-4 (IL-4). RESULTS: The lymphocytes of the asthmatic model stimulated by ConA in vitro expressed NGF mRNA in a time-dependent manner. After the lymphocytes had been cultured with IL-4 for 12 h, 24 h, 36 h, and 48 h, 50 microg/L IL-4 upregulated the expressions of NGF mRNA in a time-dependent manner and all the NGF mRNA expressions were significantly higher than the basal values at the same time(all Ps<0.01). After 0, 10, 50, and 100 microg/L IL-4 had been added for 24 h, IL-4 upregulated the expressions of NGF mRNA in a dose-dependent manner and the NGF mRNA expressions were all significantly higher than the values of the lower dose IL-4(all Ps<0.05). After the lymphocytes had been cultured with 10 mug/L IFN-gamma for 0 h, 12 h, 24 h, 36 h, and 48 h, IFN-gamma downregulated the expressions of NGF mRNA in a time-dependent manner and all the NGF mRNA expressions were significantly lower than the basal values at the same time(all Ps<0.01). After 0, 1, 10, and 50 microg/L IFN-gamma have been added for 24 h, IFN-gamma downregulated the expressions of NGF mRNA in a dose-dependent manner and all the NGF mRNA expressions were significantly lower than the values of the lower IFN-gamma dose(all Ps<0.05). CONCLUSION In the splenic lymphocytes of asthmatic rats, IL-4, one of the Th2 cytokines, can upregulate the expressions of NGF; IFN-gamma, one of the Th1 cytokines, can downregulate the expressions of NGF both in a time-dependent manner and in a dose-dependent manner. Th1/Th2 cytokine immune imbalance may indirectly induce the airway neurogenic inflammation by regulating the NGF mRNA expression.
Animals ; Asthma ; chemically induced ; immunology ; Cells, Cultured ; Cytokines ; pharmacology ; Gene Expression ; drug effects ; Interferon-gamma ; pharmacology ; Interleukin-4 ; pharmacology ; Lymphocytes ; cytology ; drug effects ; metabolism ; Male ; Nerve Growth Factors ; genetics ; Ovalbumin ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Spleen ; cytology ; immunology ; Th1 Cells ; metabolism ; Th2 Cells ; metabolism

OBJECTIVEEosinophilic airway inflammation is one of the basic characteristics of allergic asthma. Toll-like receptor is one of the most important innate immunity pattern recognition receptors. Glucocorticoids (GCS) are still the most effective treatment for asthma. However, few reports of studies on regulatory mechanism of GCS on the innate immunity system are available. The mechanism of effects of GCS on TLR4 is unclear. The present study aimed at understanding the effect of dexamethasone (DXM) on change of TLR4 and mechanism of regulatory effect of TLR4 on eosinophil (EOS) apoptosis.

METHODSTwenty-seven Sprague-Dawley (SD) rats (age 28 to 42 days, body weight 120 to 180 gram) were randomly divided into the control group, asthma group and DXM group with 9 in each. Asthma model rats were sensitized with the mixture of ovalbumin (OVA, 1 mg) and Al (OH)(3), 100 mg on day 1 and day 8, repeatedly exposed to aerosolized OVA after day 15, once a day for three days and continued for 30 minutes at every time. During the sensitization stage, 100 microg/ml DXM were prepared with DXM group for every other day, and the same doses DXM were prepared for every day on the stage of challenge. The histopathological changes of lung tissues were observed with light microscope (LM). EOS and other inflammatory cells in bronchoalveolar lavage fluid (BALF) were counted; the concentrations of OVA-sIgE in serum were measured by using "sandwich" ELISA; The expressions of TLR4 mRNA were determined by in situ hybridization, the apoptosis of EOS was detected by TUNEL.

RESULTS(1) LM showed many inflammatory cells infiltration around the bronchi and blood vessels, bronchus mucus increased, airway epithelium damage and desquamation, and airway mucous plugs in asthma group, whereas DXM group showed significantly milder changes. (2) Inflammationary cells count in BALF of asthma group was significantly higher as compared to control group (P < 0.01); compared with asthma group, the total cell count, EOS absolute count and EOS% were all significantly decreased in DXM group [(2.14 +/- 0.10) x 10(9)/L, (4.78 +/- 1.23) x 10(7)/L, (2.17 +/- 0.25)%]. (3) Levels of OVA-sIgE in serum of asthma group [(83.40 +/- 6.80) microg/ml] were significantly higher than those of the control group [(14.38 +/- 4.25) microg/ml] (P < 0.01), while those of DXM group [(45.02 +/- 7.47) microg/ml] were significantly lower than asthma group (P < 0.0 1). (4) There were no significant differences in TLR4 mRNA detected by in situ hybridization between control group (24.71 +/- 0.85) and asthma group (25.81 +/- 3.56) (P > 0.05); but it significantly increased in DXM group (29.86 +/- 3.92) as compared to asthma group. (5) The percentages of apoptotic EOS in asthma group [(7.39 +/- 1.93)%] were significantly lower than those in control group [(9.06 +/- 1.52)%] (P < 0.01); and significantly higher in DXM group [(13.33 +/- 1.09)%] than in asthma group (P < 0.01). There were significantly positive correlations between TLR4 mRNA and the percentage of apoptotic EOS (r = 0.612, P < 0.01).

CONCLUSIONDXM can decrease OVA-sIgE level, induce EOS apoptosis, which may correlate with the activation of TLR4 signal transduction.

Animals ; Apoptosis ; Asthma ; chemically induced ; immunology ; Bronchoalveolar Lavage Fluid ; cytology ; Dexamethasone ; pharmacology ; Eosinophils ; immunology ; Glucocorticoids ; pharmacology ; Immunoglobulin E ; blood ; Lung ; pathology ; Ovalbumin ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Toll-Like Receptor 4 ; immunology ; metabolism