Chronic Allergic Inflammation Research Articles

Critical Role of TSLP Receptor on CD4 T Cells for Exacerbation of Skin Inflammation.

Thymic stromal lymphopoietin (TSLP) is a key cytokine that initiates and promotes allergic inflammation both in humans and mice. It is well known that TSLP is important in initial step of inflammation by stimulating dendritic cells to promote Th2 differentiation of naive T cells. However, TSLP is abundantly produced in the late phase of inflammation, as well; therefore, we focused on the function of TSLP in chronic Th2-type inflammation. By establishing a novel (to our knowledge) chronic allergic skin inflammation mouse model with repetitive challenges of hapten after sensitization, we demonstrated that CD4 T cell-specific deletion of TSLP receptor (TSLPR) resulted in near-complete ablation of ear swelling and infiltration of CD4 T cells and eosinophils, but after second challenge. Of note, TSLPR deletion on CD4 T cells did not affect acute inflammation. As expected, transfer of Ag-sensitized wild-type CD4T cells, but not of TSLPR-deficient CD4T cells, increased skin inflammation in the model upon challenge. Furthermore, production of IL-4 from TSLPR-deficient CD4T cells in inflamed ear lesions was markedly diminished, demonstrating that TSLP-dependent IL-4 production from CD4T cells was critical for the exacerbation of skin inflammation. Similar results were obtained in Th2-type allergic skin inflammation model using MC903. Collectively, these results indicate that TSLP acts directly on CD4 T cells to elicit pathogenesis of Th2 cells, thereby having a critical role in exacerbation of skin inflammation in the chronic phase.

Effects of VAChT reduction and α7nAChR stimulation by PNU-282987 in lung inflammation in a model of chronic allergic airway inflammation

The cholinergic anti-inflammatory pathway has been shown to regulate lung inflammation and cytokine release in acute models of inflammation, mainly via α7 nicotinic receptor (α7nAChR). We aimed to evaluate the role of endogenous acetylcholine in chronic allergic airway inflammation in mice and the effects of therapeutic nAChR stimulation in this model. We first evaluated lung inflammation and remodeling on knock-down mice with 65% of vesicular acetylcholine transport (VAChT) gene reduction (KDVAChT) and wild-type(WT) controls that were subcutaneously sensitized and then inhaled with ovalbumin(OVA). We then evaluated the effects of PNU-282987(0.5-to-2mg/kg),(α7nAChR agonist) treatment in BALB/c male mice intraperitoneal sensitized and then inhaled with OVA. Another OVA-sensitized-group was treated with PNU-282987 plus Methyllycaconitine (MLA,1 mg/kg, α7nAChR antagonist) to confirm that the effects observed by PNU were due to α7nAChR. We showed that KDVAChT-OVA mice exhibit exacerbated airway inflammation when compared to WT-OVA mice. In BALB/c, PNU-282987 treatment reduced the number of eosinophils in the blood, BAL fluid, and around airways, and also decreased pulmonary levels of IL-4,IL-13,IL-17, and IgE in the serum of OVA-exposed mice. MLA pre-treatment abolished all the effects of PNU-282987. Additionally, we showed that PNU-282987 inhibited STAT3-phosphorylation and reduced SOCS3 expression in the lung. These data indicate that endogenous cholinergic tone is important to control allergic airway inflammation in a murine model. Moreover, α7nAChR is involved in the control of eosinophilic inflammation and airway remodeling, possibly via inhibition of STAT3/SOCS3 pathways. Together these data suggest that cholinergic anti-inflammatory system mainly α7nAChR should be further considered as a therapeutic target in asthma.

The state of the capillary bed in children with allergic diseases of the respiratory tract according to computer capillaroscopy of the nail bed

Introduction. The actuality of children allergic respiratory diseases problem is due to the steady increase oftheir occurrence all over the world. Computerized capillaroscopy (ССS) of the nail bed is a non-invasive and highly informative method for assessing the structural and functional parameters of capillaries in real time and physiological conditions, and so it is effectively applied in pediatric practice. However, studies in this promising direction are rare. Aim. Was to determine the microcirculation peculiarities in children suffering from respiratory allergic diseases with prolonged cough, using the method of computerized capillaroscopy of the nail bed. Materials and methods. 238 children aged from 2 to 17 years with acute and chronic respiratory diseases, accompanied by prolonged (more than 4 weeks) cough, were examined and divided into 4 groups (Gr): Gr1 (n=68) – patients with acute or exacerbation of the chronic upper respiratory tract diseases of the infectious genesis; Gr2 (n=53) – patients with lower respiratory tract infection; Gr3 (n=39) – patients with allergic rhinitis; Gr4 (n=78) – patients with bronchial asthma (BA). All patients underwent history, examination and ССS of the nail bed. Results. Patients with allergic diseases of the respiratory tract, especially with BA, were found to have structural and functional disorders of the capillary bed and a pronounced increase in the length of the perivascular zone indicating an increase in the hydration degree of the interstitial space due to chronic allergic inflammation, in contrast to children with respiratory tract infection getting changed microcirculation parameters mainly in the venous part of capillaries. Conclusion. CСS of the nail bed is a highly informative method to identify functional features of the capillaries in allergic and infectious pathologies of the respiratory system, which can be successfully used as additional criteria for their differential diagnosis.

Neuroinflammatory Gene Expression Pattern Is Similar between Allergic Rhinitis and Atopic Dermatitis but Distinct from Atopic Asthma.

Methods In the study, we included 86 children diagnosed with atopic asthma (n = 25), allergic rhinitis (n = 20), and atopic dermatitis (n = 20) and healthy control subjects (n = 21) of Caucasian origin from the Polish population. The blood leukocyte expression of 31 genes involved in neuroinflammatory response (neurotrophins, their receptors, neuropeptides, and histamine signaling pathway) was analysed using TaqMan low-density arrays. The relative expression of selected proteins from plasma was done using TaqMan Protein Assays. Statistical analysis was done using Statistica. Results Blood expression of 31 genes related to neuroimmune interactions showed significant increase in both allergic diseases, allergic rhinitis and atopic dermatitis, in comparison to the control group. We found 12 genes significantly increased in allergic rhinitis and 9 genes in which the expression was elevated in atopic dermatitis. Moreover, 9 genes with changed expression in atopic dermatitis overlapped with those in allergic rhinitis. Atopic asthma showed 5 genes with altered expression. The peripheral expression of neuroinflammatory genes in the human study was verified in target tissues (nasal epithelium and skin) in a rat model of allergic inflammation. Conclusions A common pattern of neuroinflammatory gene expression between allergic rhinitis and atopic dermatitis may reflect similar changes in sensory nerve function during chronic allergic inflammation.

Treatment with inhaled formulation of angiotensin-(1-7) reverses inflammation and pulmonary remodeling in a model of chronic asthma.

Asthma is characterized by inflammation, pulmonary remodeling and bronchial hyperresponsiveness. We have previously shown that treatment with angiotensin-(1-7) [Ang-(1-7)] promotes resolution of eosinophilic inflammation and prevents chronic allergic lung inflammation. Here, we evaluated the effect of treatment with the inclusion compound of Ang-(1-7) in hydroxypropyl β-cyclodextrin (HPβCD) given by inhalation on pulmonary remodeling in an ovalbumin (OVA)-induced chronic allergic lung inflammation. Mice were sensitized to ovalbumin (OVA; 4 injections over 42 days, 14 days apart) and were challenged 3 times per week, for 4 weeks (days 21-46). After the 2nd week of challenge, mice were treated with Ang-(1-7) by inhalation (4.5 μg of Ang-(1-7) included in 6.9 μg of HPβCD for 14 days, i.e. days 35-48). Mice were killed 72 h after the last challenge and blood, bronchoalveolar lavage fluid (BALF) and lungs were collected. Histology and morphometric analysis were performed in the lung. Metalloproteinase (MMP)-9 and MMP-12 expression and activity, IL-5, CCL11 in the lung and plasma IgE were measured. After 2 weeks of OVA challenge there was an increase in plasma IgE and in inflammatory cells infiltration in the lung of asthmatic mice. Treatment with inhaled administration of Ang-(1-7)/HPβCD for 14 days reduced eosinophils, IL5, CCL11 in the lung and plasma IgE. Treatment of asthmatic mice with Ang-(1-7)/HPβCD by inhalation reversed pulmonary remodeling by reducing collagen deposition and MMP-9 and MMP-12 expression and activity. These results show for the first time that treatment by inhalation with Ang-(1-7) can reverse an installed asthma, inhibiting pulmonary inflammation and remodeling.

Skin-resident natural killer T cells induce cutaneous allergic inflammation in atopic dermatitis

Abstract Natural killer T (NKT) cells are unconventional T cells that bridge innate and adaptive immunity. NKT cells have been implicated in the development of atopic dermatitis (AD). Here, we demonstrate that CXCR4 and its cognate ligand CXCL12 are significantly up-regulated in human AD skin in global transcriptomic analysis; proteomic analysis revealed that CXCR4+ NKT cells are enriched in AD skin and are consistently elevated in our AD mouse model. Adoptive transfer of allergen-specific NKT cells confer antigen-specific cutaneous inflammation, and predominant skin NKT cells are CXCR4+ and CD69+, similar to tissue-resident memory T (TRM) cells. Skin-resident NKT cells uniquely expressed CXCR4, which was confirmed using a parabiosis system. Intravital imaging showed that CXCR4+ NKT cells preferentially trafficked to a CXCL12-rich area, forming an enriched CXCR4+ NKTRM/CXCL12+ cell cluster, which developed acute and chronic allergic inflammation. CXCR4+ NKTRM cells may form a niche to develop AD, where CXCL12 is highly expressed.

IL-9 Represses Intestinal Granzyme A Positive CD4 T Cells in Mice with Allergic Airway Inflammation

Abstract Mediated by immune responses in the airways, symptoms of allergic airway diseases include shortness of breath, difficulty breathing, and wheezing. Responses in distant tissues, such as increased lymphocyte proliferation and cytokine secretion, are also exhibited. How airway sensitization mediates these distant effects is unclear. We recently described the development and function of granzyme A-expressing T cells that control intestinal inflammation. Using models of chronic and memory allergic airway inflammation, we now show that a granzyme A expressing CD4 T cell population in the intestine increases during these diseases. This response is amplified in mice that lack IL-9 signaling through a deficiency in IL-9 receptor levels (IL9RKO) or receive an IL-9 antibody blockade. In a chronic intranasal allergen challenge model, we saw elevated levels of granzyme A expressing CD4 T cells in IL9RKO mice when compared to wild-type controls. In a memory internasal allergen model using wild-type mice (chronic allergen exposure, followed by an allergen-free rest period, and an allergen re-exposure), granzyme A expressing cells in the intestine were increased upon IL-9 antibody blockade. Blocking IL-9 or administering IL-9 to naïve mice or cell cultures that generate granzyme A expressing T cells did not affect cell prevalence. Therefore, concurrent allergic airway inflammation seems to be required for the proliferation of these granzyme A expressing T cells. Together, these studies suggest that allergic airway inflammation increases granzyme A expressing CD4 T cells in the intestine and that IL-9 attenuates this effect. Moreover, these results show that allergic airway inflammation impacts immunity at a distant mucosal site.

More Than Just a Barrier: The Immune Functions of the Airway Epithelium in Asthma Pathogenesis.

Allergic bronchial asthma is a chronic disease of the airways that is characterized by symptoms like respiratory distress, chest tightness, wheezing, productive cough, and acute episodes of broncho-obstruction. This symptom-complex arises on the basis of chronic allergic inflammation of the airway wall. Consequently, the airway epithelium is central to the pathogenesis of this disease, because its multiple abilities directly have an impact on the inflammatory response and thus the formation of the disease. In turn, its structure and functions are markedly impaired by the inflammation. Hence, the airway epithelium represents a sealed, self-cleaning barrier, that prohibits penetration of inhaled allergens, pathogens, and other noxious agents into the body. This barrier is covered with mucus that further contains antimicrobial peptides and antibodies that are either produced or specifically transported by the airway epithelium in order to trap these particles and to remove them from the body by a process called mucociliary clearance. Once this first line of defense of the lung is overcome, airway epithelial cells are the first cells to get in contact with pathogens, to be damaged or infected. Therefore, these cells release a plethora of chemokines and cytokines that not only induce an acute inflammatory reaction but also have an impact on the alignment of the following immune reaction. In case of asthma, all these functions are impaired by the already existing allergic immune response that per se weakens the barrier integrity and self-cleaning abilities of the airway epithelium making it more vulnerable to penetration of allergens as well as of infection by bacteria and viruses. Recent studies indicate that the history of allergy- and pathogen-derived insults can leave some kind of memory in these cells that can be described as imprinting or trained immunity. Thus, the airway epithelium is in the center of processes that lead to formation, progression and acute exacerbation of asthma.

Diagnostic markers of allergic bronchopulmonary aspergillosis in patients with severe asthma.

Allergic bronchopulmonary aspergillosis (ABPA) is a lung disease in patients with asthma or cystic fibrosis (CF) caused by chronic allergic inflammation to Aspergillus spp. antigens. The role of different immunological mediators in the formation of chronic allergic inflammation in patients with ABPA is not sufficiently explored. This study aimed to investigate serum levels of thymic stromal lymphopoietin (TSLP), thymus and activated chemokine (TARC) as well as IL-8 in patients with ABPA, and to evaluate their diagnostic and monitoring value in the disease. Prospective study included 21 patients with ABPA, 25 patients with severe asthma with fungal sensitisation (SAFS), 37 patients with severe asthma without fungal sensitisation (SAwFS), and 16 healthy people. In patients with ABPA, the serum levels of biomarkers were determined at baseline and after 12weeks of itraconazole therapy. Serum levels of total IgE, Aspergillus-fumigatus-specific IgE, TSLP, TARC, IL-8 were analysed by enzyme-linked immunosorbent assay. In patients with ABPA we established significantly higher serum levels of TARC, IL-8, total IgE, Aspergillus-fumigatus-specific IgE and peripheral blood eosinophil counts, compared to patients with SAwFS. There were no differences in TSLP levels between the examined groups of patients. Serum TARC levels were positively correlated to serum total IgE levels, Afumigatus-specific IgE levels and peripheral blood eosinophil counts and also negatively correlated to lung function (FEV1 ). Longitudinally, serum levels TARC, total IgE and peripheral blood eosinophil counts significant decreased after treatment of ABPA. Thymus and activated chemokine is a useful test in diagnosing and monitoring response to the antifungal treatment of patients with ABPA.

The role of mutations in metalloproteinases and the epithelial growth factor receptor genes in the pathogenesis of children bronchial asthma

The pathogenesis of bronchial asthma (BA) is based on chronic allergic inflammation of bronchi, which affects not only microcirculation disorders, activation of lipid peroxidation, but also tissue remodeling. Matrix metalloproteinases (MMP) and epithelial growth factor (EGF) play a significant role in bronchial remodelling processes. This paper attempts to investigate the effect of gene mutations ММР and EGFR on the development of BA as well as evaluate the role of intergenic interaction. Methods . Polymorphic variants were studied in BA patients and control group patients by allelspecific polymerase chain reaction (using SNP-express reagent kits). 2073A>T gene EGFR , 320A>C gene MMP20 , 837Т>C gene MMP20 и - 8202A>G gene MMP9 . Results . The analysis of the genetic study results showed statistically significant differences in the frequency of alleles and genotypes in polymorphism. 2073A>T gene EGFR among BA patients and control group children ( p G gene MMP9 and 2073A>T gene EGFR have a synergistic effect on each other, increasing the risk of developing BA in children. Conclusion . According to the results of studies it was found that the risk of BA development is significantly increased in homozygotes on T-allel polymorphic variant 2073A>T gene EGFR , with the frequency of occurrence of genotypes and alleles of this polymorphism statistically significantly different from the control group ( p < 0.05).

Early Metabolic Syndrome (MetS) in Chronic Rhesus Macaque Model of Human Allergic Asthma

Human asthma, obesity, MetS, overt Type 2 diabetes, and related sequelae such as cardiovascular diseases, account for much of the mortality and morbidity worldwide. The etiology and complex physiological mechanisms underlying these pathological states intersect within the human body – and within Rhesus macaques. Much like humans, these animals (in captivity) often develop spontaneous, age‐related obesity. Hence, these animals are ideally suited for investigations of obesity and metabolism, as well as chronic allergic asthma.In 2013, twenty animals were sensitized by i.p. injection of house dust mite antigen (HDM) adsorbed to alum; airway sensitization and maintenance were accomplished by exposure to aerosolized HDM (aeroHDM) at ≥ 2‐week intervals, to a dose that induced an acute asthmatic response: ≥ 100% increase in lung resistance, ≥ 40% decrease in dynamic compliance, and/or peripheral oxygen saturation ≤ 70%. Periodically, we assessed the late phase asthmatic response 24 hours after aeroHDM exposure: airway hyperreactivity was assessed by aerosolized methacholine challenge; pulmonary inflammation was assessed by bronchoalveolar lavage. Occasionally animals were also exposed to an experimental asthma therapeutic.In 2018, ten animals had developed obesity and were suspected to harbor other clinical manifestations of MetS. Retrospective analyses confirmed relative hypertension in animals that had robust responsiveness to aeroHDM and were &gt; 16 kg. Using archived frozen serum samples, we reconstructed the biochemical history of adiposity development and glucose metabolism ‐ a story that was evolving coincident with chronic exposures to both Diet A and aeroHDM (Fig. 1). By age 10 years, 4/5 of the largest animals (body weight, 21 ± 2 kg; waist circumference in lateral recumbency, 68 ± 5 cm; BMI using crown‐to‐rump length, 53 ± 3 kg/m2: values are mean ± SD) had insulin resistance (peak HOMA‐IR, 61 ± 29) associated with leptin &gt; 14 ng/ml and total adiponectin &lt; 3.5 μg/ml; 3/5 animals had dyslipidemia (Fig. 2); 1/5 animals had diabetes by age 8 years – 4 to 6 years earlier than would be expected based on non‐human primate literature. Biomarkers of inflammation and oxidative stress are outstanding.In July 2019, six months after switching to lower carbohydrate/higher protein Diet B, and &gt; 12 months since the last aeroHDM exposure: all animals lost weight coincident with larger animals resolving insulin resistance, dyslipidemia, and diabetes. As seen in some obese asthmatic humans, larger animals had higher pulmonary inflammation (especially neutrophilic) and higher airway hyperreactivity to aerosolized methacholine.We concluded that chronic allergic inflammation synergized with inflammation of developing adiposity, accelerating onset of MetS in susceptible animals. We hypothesize that resumption of chronic periodic aeroHDM exposure will trigger more rapid progression/re‐establishment of MetS, IR, and eventually overt Type 2 diabetes if we do not intervene.Historical event timeline.Figure 1Body weight and serum triglycerides of 5 largest animals (mean ± SD: n=3 to 5 for each time point). Gray vertical bar: gradual transition to lower carbohydrate/higher protein Diet B.Figure 2

ILC2 activation by keratinocyte-derived IL-25 drives IL-13 production at sites of allergic skin inflammation

BackgroundAtopic dermatitis skin lesions demonstrate increased expression of IL-25 by keratinocytes and increased numbers of type 2 innate lymphoid cells (ILC2s) that express high levels of IL-25 receptor (IL-25R). IL-13 is expressed in atopic dermatitis skin lesions and plays an important role in pathogenesis of the disease.ObjectiveOur aim was to determine the role of IL-25 and ILC2s in a mouse model of antigen-driven allergic skin inflammation.MethodsWild-type mice; mice that express an Il13-driven enhanced green fluorescent protein; and mice that lack IL-25R, IL-25 in keratinocytes, or IL-13 or IL-25R in ILC2s were subjected to acute or chronic epicutaneous sensitization with ovalbumin. Sensitized skin was examined by histology for epidermal thickening. Cellular infiltrates were analyzed for surface markers and intracellular expression of enhanced green fluorescent protein by flow cytometry. Gene expression was quantitated by RT quantitative PCR.ResultIn both acute and chronic antigen-driven allergic skin inflammation, signaling by keratinocyte-derived IL-25 in ILC2s is important for epidermal hyperplasia, dermal infiltration by CD4+ T cells, and cutaneous expression of Il13 and the IL-13–dependent TH2-cell–attracting chemokines Cc17 and Ccl22. ILCs are the major source of IL-13 in acutely sensitized mouse skin, whereas T cells are its major source in chronically sensitized mouse skin.ConclusionILC2 activation by IL-25 is essential for IL-13 expression at sites of allergic skin inflammation.

Virgin Coconut Oil Supplementation Prevents Airway Hyperreactivity of Guinea Pigs with Chronic Allergic Lung Inflammation by Antioxidant Mechanism.

Asthma is a chronic inflammatory disease of the airways characterized by immune cell infiltrates, bronchial hyperresponsiveness, and declining lung function. Thus, the possible effects of virgin coconut oil on a chronic allergic lung inflammation model were evaluated. Morphology of lung and airway tissue exhibited peribronchial inflammatory infiltrate, epithelial hyperplasia, and smooth muscle thickening in guinea pigs submitted to ovalbumin sensitization, which were prevented by virgin coconut oil supplementation. Additionally, in animals with lung inflammation, trachea contracted in response to ovalbumin administration, showed a greater contractile response to carbachol (CCh) and histamine, and these responses were prevented by the virgin coconut oil supplementation. Apocynin, a NADPH oxidase inhibitor, did not reduce the potency of CCh, whereas tempol, a superoxide dismutase mimetic, reduced potency only in nonsensitized animals. Catalase reduced the CCh potency in nonsensitized animals and animals sensitized and treated with coconut oil, indicating the participation of superoxide anion and hydrogen peroxide in the hypercontractility, which was prevented by virgin coconut oil. In the presence of L-NAME, a nitric oxide synthase (NOS) inhibitor, the CCh curve remained unchanged in nonsensitized animals but had increased efficacy and potency in sensitized animals, indicating an inhibition of endothelial NOS but ineffective in inhibiting inducible NOS. In animals sensitized and treated with coconut oil, the CCh curve was not altered, indicating a reduction in the release of NO by inducible NOS. These data were confirmed by peribronchiolar expression analysis of iNOS. The antioxidant capacity was reduced in the lungs of animals with chronic allergic lung inflammation, which was reversed by the coconut oil, and confirmed by analysis of peribronchiolar 8-iso-PGF2α content. Therefore, the virgin coconut oil supplementation reverses peribronchial inflammatory infiltrate, epithelial hyperplasia, smooth muscle thickening, and hypercontractility through oxidative stress and its interactions with the NO pathway.

Effects of physical exercise on lung inflammation in animal models of chronic allergic lung inflammation: a systematic review.

We performed a systematic review to identify and summarize the effects of distinctive aerobic exercise (AE) protocols on chronic allergic lung inflammation reported in asthma animal models. We identified 255 preclinical studies of asthma and AE protocols by comprehensive searches in PubMed, ScienceDirect and LILACS for peer-reviewed journals, using the search components "exercise," "lung inflammation," and "asthma," without restrictions on publication date. Twenty-two studies were selected that met all eligibility criteria. Most studies used an ovalbumin experimental model and performed experiments with BALB/c mice. Most studies performed treadmill AE, using protocols of 30 to 60 minutes, 3 to 5 times/week, for 4 to 8 weeks. The results showed that the effects of AE on lungs were protocol dependent, but generaly, there was a decrease in inflammatory cell influx and Th2 cytokines, as well as an increase in anti-inflammatory defenses. However, the immunoregulation of globulins and nitric oxide levels in asthma seemed to be associated with the onset of AE. The results suggest that AE plays an important immunoregulatory role in animal models of asthma, with effects mainly mediated by increased anti-inflammatory defenses and reduced Th2 response. In parallel, prophylactic and therapeutic AE also played important roles in decreasing bronchial responsiveness and attenuating lung remodeling in animal models of asthma, secondary outcomes in this systematic review. The review protocol was published for free access in October 2017 on the Systematic Review Facility (SyRF) platform (http://syrf.org.uk/protocols/).

Effect of anti-IL17 and/or Rho-kinase inhibitor treatments on vascular remodeling induced by chronic allergic pulmonary inflammation.

Background and aims:Expansion and morphological dysregulation of the bronchial vascular network occurs in asthmatic airways. Interleukin (IL) -17 and Rho-kinase (ROCK) are known to act in inflammation control and remodeling. Modulation of Rho-kinase proteins and IL-17 may be a promising approach for the treatment of asthma through the control of angiogenesis. Our objective was to analyze the effects of treatment with anti-IL17 and/or Rho-kinase inhibitor on vascular changes in mice with chronic allergic pulmonary inflammation.Methods:Sixty-four BALB/c mice, with pulmonary inflammation induced by ovalbumin were treated with anti-IL17A (7.5/µg per dose, intraperitoneal) and/or Rho-kinase inhibitor (Y-27632-10 mg/kg, intranasal), 1 h before each ovalbumin challenge (22, 24, 26, and 28/days). Control animals were made to inhale saline. At the end of the protocol, lungs were removed, and morphometric analysis was performed to quantify vascular inflammatory, remodeling, and oxidative stress responses.Results:Anti-IL17 or Rho-kinase inhibitor reduced the number of CD4+, CD8+, dendritic cells, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, Rho-kinase 1 and 2, transforming growth factor (TGF-β), vascular endothelial growth factor (VEGF), nuclear factor (NF)-KappaB, iNOS, metalloproteinase (MMP)-9, MMP-12, metalloproteinase inhibitor-1 (TIMP-1), FOXP-3, signal transducer and activator of transcription 1 (STAT1) and phospho-STAT1-positive cells, and actin, endothelin-1, isoprostane, biglycan, decorin, fibronectin and the collagen fibers volume fraction compared with the ovalbumin group (p < 0.05). The combination treatment, when compared with anti-IL17, resulted in potentiation of decrease in the number of IL1β- and dendritic cells-positive cells. When we compared the OVA-RHO inhibitor-anti-IL17 with OVA-RHO inhibitor we found a reduction in the number of CD8+ and IL-17, TGF-β, and phospho-STAT1-positive cells and endothelin-1 in the vessels (p < 0.05). There was an attenuation in the number of ROCK 2-positive cells in the group with the combined treatment when compared with anti-IL17 or Rho-kinase inhibitor-treated groups (p < 0.05).Conclusion:We observed no difference in angiogenesis after treatment with Rho-kinase inhibitor and anti-IL17. Although the treatments did not show differences in angiogenesis, they showed differences in the markers involved in the angiogenesis process contributing to inflammation control and vascular remodeling. The reviews of this paper are available via the supplemental material section.

Modulation of the humoral immune response by constitutively active STAT6 expression in murine B cells.

The transcription factor STAT6 regulates gene expression in response to IL-4 and IL-13. To further investigate how activated STAT6 modulates B cells development and function in vivo, we characterized mice that express a constitutively active version specifically in B cells. CD19Cre_STAT6vt mice show spontaneous phosphorylation and nuclear translocation of STAT6 in B cells. About 80 genes were more than twofold up- or downregulated in splenic B cells from CD19Cre_STAT6vt as compared to control mice. B cell development, tissue localization, and populations of follicular and marginal zone B cells, B1 B cells, GC B cells, and plasma cells (PCs) appeared to be normal. However, the number of IgE+ and IgG1+ GC B cells and PCs as well as serum IgE and IgG1 levels were increased in CD19Cre_STAT6vt mice. Infection with Lymphocytic choriomeningitis virus associated with high levels of TNF and IFN-γ did not prevent the development of a significantly increased IgE and IgG1 response against the virus in CD19Cre_STAT6vt mice. These results suggest that prolonged STAT6 activation during chronic allergic inflammation may result in IgE responses during subsequent viral or bacterial infection that could further stimulate mast cell activation even in the absence of the initial allergic response.

Inhibition of MAPK and STAT3-SOCS3 by Sakuranetin Attenuated Chronic Allergic Airway Inflammation in Mice.

Asthma allergic disease is caused by airway chronic inflammation. Some intracellular signaling pathways, such as MAPK and STAT3-SOCS3, are involved in the control of airway inflammation in asthma. The flavonoid sakuranetin demonstrated an anti-inflammatory effect in different asthma models. Our aim was to clarify how sakuranetin treatment affects MAPK and STAT3-SOCS3 pathways in a murine experimental asthma model. Mice were submitted to an asthma ovalbumin-induction protocol and were treated with vehicle, sakuranetin, or dexamethasone. We assayed the inflammatory profile, mucus production, and serum antibody, STAT3-SOCS3, and MAPK levels in the lungs. Morphological alterations were also evaluated in the liver. LPS-stimulated RAW 264.7 cells were used to evaluate the effects of sakuranetin on nitric oxide (NO) and cytokine production. In vivo, sakuranetin treatment reduced serum IgE levels, lung inflammation (eosinophils, neutrophils, and Th2/Th17 cytokines), and respiratory epithelial mucus production in ovalbumin-sensitized animals. Considering possible mechanisms, sakuranetin inhibits the activation of ERK1/2, JNK, p38, and STAT3 in the lungs. No alterations were found in the liver for treated animals. Sakuranetin did not modify in vitro cell viability in RAW 264.7 and reduced NO release and gene expression of IL-1β and IL-6 induced by LPS in these cells. In conclusion, our data showed that the inhibitory effects of sakuranetin on eosinophilic lung inflammation can be due to the inhibition of Th2 and Th17 cytokines and the inhibition of MAPK and STAT3 pathways, reinforcing the idea that sakuranetin can be considered a relevant candidate for the treatment of inflammatory allergic airway disease.

Effects of the serine protease inhibitor rBmTI-A in an experimental mouse model of chronic allergic pulmonary inflammation

To evaluate whether a recombinant serine protease inhibitor (rBmTI-A) modulates inflammation in an experimental model of chronic allergic lung inflammation. Balb/c mice were divided into four groups: SAL (saline), OVA (sensitized with ovalbumin), SAL + rBmTI-A (control treated with rBmTI-A) and OVA + rBmTI-A (sensitized with ovalbumin and treated with rBmTI-A). The animals received an intraperitoneal injection of saline or ovalbumin, according to the group. The groups received inhalation with saline or ovalbumin and were treated with rBmTI-A or saline by nasal instillation. After 29 days, we evaluated the respiratory mechanics; bronchoalveolar lavage fluid (BALF); cytokines; MMP-9, TIMP-1; eosinophils; collagen and elastic fibre expression in the airways; and the trypsin-like, MMP-1, and MMP-9 lung tissue proteolytic activity. Treatment with rBmTI-A reduced the trypsin-like proteolytic activity, the elastance and resistance maximum response, the polymorphonuclear cells, IL-5, IL-10, IL-13 and IL-17A in the BALF, the expression of IL-5, IL-13, IL-17, CD4+, MMP-9, TIMP-1, eosinophils, collagen and elastic fibres in the airways of the OVA + rBmTI-A group compared to the OVA group (p < 0.05). rBmTI-A attenuated bronchial hyperresponsiveness, inflammation and remodelling in this experimental model of chronic allergic pulmonary inflammation. This inhibitor may serve as a potential therapeutic tool for asthma treatment.

H1-Antihistamines for Allergic Diseases: Old Aged but Not Old-Fashioned Drugs

Histamine is a chemical messenger synthesized from the amino acid histidine by L-histidine decarboxylase. It plays an important role in the system of immunoregulation and in acute and chronic allergic inflammation binding to four subtypes of receptors H1, H2, H3 and H4, described as heptahelical transmembrane molecules that activate specific G-proteins. These receptors placed on the membranes of different cellular jambs (mast cells, endothelial cells, sensory nerve fibres, bronchial smooth muscle) cause different biological actions: Vasodilatation, increased vascular permeability, itching, smooth muscle contraction, coronary spasm, sleep-wake rhythm regulation. Histamine interaction with H1-receptors potentially leads to increasing antigen-presenting cell capacity, release of histamine and other mediators from mast cells and basophils inducing cellular adhesion molecule expression and chemotaxis of eosinophils and neutrophils.

Epithelial cell-derived prostaglandin D2 inhibits chronic allergic lung inflammation in mice.

The precise role of prostaglandin D (PGD)2 in allergic lung inflammation remains controversial. Here, we aimed to clarify the role of PGD2 in chronic allergic lung inflammation using hematopoietic PGD synthase (H-PGDS)-deficient mice. Repeated intranasal administration of ovalbumin (OVA) resulted in eosinophilic infiltration and mucin production in the lungs of wild type (WT) mice, leading to respiratory dysfunction. H-PGDS deficiency exacerbated these effects, which were accompanied by increased mRNA expression of TNF-α and eosinophil chemoattractants. The bronchial epithelium expressed both H-PGDS and TNF-α in the inflamed WT lung, and H-PGDS deficiency increased TNF-α expression further. In cultured bronchial tissue of WT mice, treatment with LPS elevated mRNA expression of TNF-α and eosinophil chemoattractants. H-PGDS deficiency promoted the expression of these factors, which was inhibited by treatment with PGD2 receptor, D prostanoid (DP) receptor agonist, or PGD2 metabolite 15-deoxy-Δ12,14-PGJ2 (15d-PGJ2). Treatment with TNF-α receptor antibody inhibited eosinophil chemoattractant expression. In vivo, administration of DP agonist or 15d-PGJ2 inhibited OVA-induced allergic lung inflammation. Bronchial epithelial cell-derived PGD2 attenuated lung eosinophilic infiltration with chronic allergic inflammation; these phenomena are at least partly attributed to the inhibition of TNF-α production via DP activation or 15-deoxy-Δ12,14-PGJ2 signaling.-Maehara, T., Nakamura, T., Maeda, S., Aritake, K., Nakamura, M., Murata, T. Epithelial cell-derived prostaglandin D2 inhibits chronic allergic lung inflammation in mice.