Janus kinase-3 dependent inflammatory responses in allergic asthma

Gene editing in allergic diseases: Identification of novel pathways and impact of deleting allergen genes

Gene editing technology has emerged as a powerful tool in all aspects of health research and continues to advance our understanding of critical and essential elements in disease pathophysiology. The clustered regularly interspaced short palindromic repeats (CRISPR) gene editing technology has been used with precision to generate gene knockouts, alter genes, and identify genes that cause disease. The full spectrum of allergic/atopic diseases, in part because of shared pathophysiology, is ripe for studies with this technology. In this way, novel culprit genes are being identified and allow for manipulation of triggering allergens to reduce allergenicity and disease. Notwithstanding current limitations on precision and potential off-target effects, newer approaches are rapidly being introduced to more fully understand specific gene functions as well as the consequences of genetic manipulation. In this review, we examine the impact of editing technologies of novel genes relevant to peanut allergy and asthma as well as how gene modification of common allergens may lead to the deletion of allergenic proteins.

IL-4/IL-13 axis as therapeutic targets in allergic rhinitis and asthma

Allergic rhinitis (AR) is a common disorder of the upper airway, while asthma is a disease affecting the lower airway and both diseases are usually comorbid. Interleukin (IL)-4 and IL-13 are critical cytokines in the induction of the pathogenic Th2 responses in AR and asthma. Targeting the IL-4/IL-13 axis at various levels of its signaling pathway has emerged as promising targeted therapy in both AR and asthma patient populations. In this review, we discuss the biological characteristics of IL-4 and IL-13, their signaling pathways, and therapeutic antibodies against each cytokine as well as their receptors. In particular, the pleiotropic roles of IL-4 and IL-13 in orchestrating Th2 responses in AR and asthma patients indicate that dual IL-4/IL-13 blockade is a promising therapeutic strategy for both diseases.

Precision medicine in the allergy clinic: the application of component resolved diagnosis

INTRODUCTION

A precise diagnosis is key for the optimal management of allergic diseases and asthma. In vivo or in vitro diagnostic methods that use allergen extracts often fail to identify the molecules eliciting the allergic reactions.

AREAS COVERED

Component-resolved diagnosis (CRD) has solved most of the limitations of extract-based diagnostic procedures and is currently valuable tool for the precision diagnosis in the allergy clinic, for venom and food allergy, asthma, allergic rhinitis, and atopic dermatitis. Its implementation in daily practice facilitates: a) the distinction between genuine multiple sensitizations and cross-reactive sensitization in polysensitized patients; b) the prediction of a severe, systemic reaction in food or insect venom allergy; c) the optimal selection of allergen immunotherapy based on the patient sensitization profile. This paper describes its main advantages and disadvantages, cost-effectiveness and future perspectives.

EXPERT OPINION

The diagnostic strategy based on CRD is part of the new concept of precision immunology, which aims to improve the management of allergic diseases.

CRISPR-Cas9: A Preclinical and Clinical Perspective for the Treatment of Human Diseases

At present, the idea of genome modification has revolutionized the modern therapeutic research era. Genome modification studies have traveled a long way from gene modifications in primary cells to genetic modifications in animals. The targeted genetic modification may result in the modulation (i.e., either upregulation or downregulation) of the predefined gene expression. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated nuclease 9 (Cas9) is a promising genome-editing tool that has therapeutic potential against incurable genetic disorders by modifying their DNA sequences. In comparison with other genome-editing techniques, CRISPR-Cas9 is simple, efficient, and very specific. This enabled CRISPR-Cas9 genome-editing technology to enter into clinical trials against cancer. Besides therapeutic potential, the CRISPR-Cas9 tool can also be applied to generate genetically inhibited animal models for drug discovery and development. This comprehensive review paper discusses the origin of CRISPR-Cas9 systems and their therapeutic potential against various genetic disorders, including cancer, allergy, immunological disorders, Duchenne muscular dystrophy, cardiovascular disorders, neurological disorders, liver-related disorders, cystic fibrosis, blood-related disorders, eye-related disorders, and viral infection. Finally, we discuss the different challenges, safety concerns, and strategies that can be applied to overcome the obstacles during CRISPR-Cas9-mediated therapeutic approaches.

Discovery of potential asthma targets based on the clinical efficacy of Traditional Chinese Medicine formulas

ETHNOPHARMACOLOGICAL RELEVANCE

Standard therapy for asthma, a highly heterogeneous disease, is primarily based on bronchodilators and immunosuppressive drugs, which confer short-term symptomatic relief but not a cure. It is difficult to discover novel bronchodilators, although potential new targets are emerging. Traditional Chinese Medicine (TCM) formulas have been used to treat asthma for more than 2000 years, forming the basis for representative asthma treatments.

AIM OF THE STUDY

Based on the efficacy of TCM formulas, anti-asthmatic herbal compounds bind proteins are potential targets for asthma therapy. This analysis will provide new drug targets and discovery strategies for asthma therapy.

MATERIALS AND METHODS

A list of candidate herbs for asthma was selected from the classical formulas (CFs) of TCM for the treatment of wheezing or dyspnea recorded in Treatise on Cold Damage and Miscellaneous Diseases (TCDMD) and from modern herbal formulas identified in the SAPHRON TCM Database using the keywords "wheezing" or "dyspnea". Compounds in the selected herbs and compounds that directly bind target proteins were acquired by searching the Herbal Ingredients' Targets Database (HITD), TCM Data Bank (TCMDB) and TCM Integrated Database (TCMID). Therapeutic targets of conventional medicine (CM) for asthma were collected by searching Therapeutic Target Database (TTD), DrugBank and PubMed as supplements. Finally, the enriched gene ontology (GO) terms of the targets were obtained using the Database for Annotation Visualization and Integrated Discovery (DAVID) and protein-protein interactions (PPI) networks were constructed using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). The effects of two selected TCM compounds, kaempferol and ginkgolide A, on cellular resistance in human airway smooth muscle cells (ASMCs) and pulmonary resistance in a mouse model were investigated.

RESULTS

The list of 32 candidate herbs for asthma was selected from 10 CFs for the treatment of wheezing or dyspnea recorded in TCDMD and 1037 modern herbal formulas obtained from the SAPHRON TCM Database. A total of 130 compounds from the 32 selected herbs and 68 herbal compounds directly bind target proteins were acquired from HITD and TCMDB. Eighty-eight therapeutic targets of CM for asthma were collected by searching TTD and PubMed as supplements. DAVID and STRING analyses showed targets of TCM formulas are primarily related to cytochrome P450 (CYP) family, transient receptor potential (TRP) channels, matrix metalloproteinases (MMPs) and ribosomal protein. Both TCM formulas and CM act on the same types of targets or signaling pathways, such as G protein-coupled receptors (GPCRs), steroid hormone receptors (SHRs), and JAK-STAT signaling pathway. The proteins directly targeted by herbal compounds, TRPM8, TRPA1, TRPV3, CYP1B1, CYP2B6, CYP1A2, CYP3A4, CYP1A1, PPARA, PPARD, NR1I2, MMP1, MMP2, ESR1, ESR2, RPLP0, RPLP1 and RPLP2, are potential targets for asthma therapy. In vitro results showed kaempferol (1 × 10^-2 mM) and ginkgolide A (1 × 10^-5 mM) significantly increased the cell index (P < 0.05 vs. histamine, n = 3) and therefore relaxed human ASMCs. In vivo results showed kaempferol (145 μg/kg) and ginkgolide A (205 μg/kg) significantly reduced pulmonary resistance (P < 0.05 vs. methacholine, n = 6).

CONCLUSION

Potential target discovery for asthma treatment based on the clinical effectiveness of TCM is a feasible strategy.

Preformulation and Evaluation of Tofacitinib as a Therapeutic Treatment for Asthma

Preformulation studies on tofacitinib citrate, a small molecule JAK3 specific inhibitor, have not been previously reported in literature. We therefore conducted several preformulation studies on tofacitinib citrate, and its free base, to better understand factors that affect its solubility, stability, and solid-state characteristics. Further, the results of the preformulation studies helped facilitate the development of a nebulized formulation of tofacitinib citrate for inhalational delivery to house dust mite allergen-challenged, BALB/c mice as a potential treatment for eosinophilic asthma. The preformulation results indicated tofacitinib having a basic pKa of 5.2, with its stability dependent on pH, ionic strength, and temperature. Degradation of tofacitinib follows apparent first-order kinetics. In order to maximize stability of the drug, ionic strength and temperature should be minimized, with an optimal range pH between 2.0 and 5.0. Additionally, our findings demonstrate that tofacitinib citrate can successfully be nebulized at a suitable droplet size for inhalation (1.2 ± 0.2 μm MMAD) through a nose-only chamber. Animals dosed with tofacitinib citrate demonstrated marked reductions in BAL eosinophils and total protein concentrations following HDM challenge. These data suggest that tofacitinib citrate represents the potential to be an effective therapy for eosinophilic asthma.

Investigation into the Role of PI3K and JAK3 Kinase Inhibitors in Murine Models of Asthma

Asthma is a clinical disorder commonly characterized by chronic eosinophilic inflammation, remodeling and hyper responsiveness of the airways. However, the kinases like Phosphoinositide 3 kinase (PI3K) and Janus kinase 3 (JAK3) are involved in mast cell proliferation, activation, recruitment, migration, and prolonged survival of inflammatory cells. The present study was designed to evaluate the in-vivo comparative effects of two kinase inhibitors on airway inflammation and airway remodeling in acute and chronic models of asthma. Mice were sensitized twice intra-peritoneally and then challenged by inhalation with ovalbumin (OVA). They developed an extensive inflammatory response, goblet cell hyperplasia, collagen deposition, airway smooth muscle thickening similar to pathologies observed in human asthma. The effects of PI3K inhibitor (30 mg/kg, p.o), JAK3 inhibitor (30 mg/kg, p.o) and Dexamethasone (0.3 mg/kg) on airway inflammation and remodeling in OVA sensitized/challenged BALB/c mice were evaluated. Twenty-four hours after the final antigen challenge, bronchoalveolar lavage (BAL) and histological examinations were carried out. It was observed that kinase inhibitors significantly reduced airway inflammation as evidenced by the decrease in pro inflammatory cytokines in BALF and lung homogenate and inflammatory cell count in sensitized mice after allergen challenge. Lung histological analysis showed increased infiltration of inflammatory cells, hyperplasia of goblet cells and the collagen deposition, which were significantly reduced with kinase inhibitor. In conclusion, our data suggest that PI3K and JAK3 inhibitors showed promising alternative therapeutic activity in asthma, which might significantly counteract the airway inflammation in patients with allergic asthma.

Targeting the JAK-STAT pathway in the treatment of 'Th2-high' severe asthma

Severe asthma is a heterogeneous disease characterized by reversible airway obstruction, chronic inflammation and airway remodeling. Phenotyping and/or endotyping can lead to a more personalized treatment strategy, improving the efficacy of novel drugs. Atopic asthma is associated with high levels of Th2 cells, implicated in a number of inflammatory responses. Differentiation of these cells from naive T cells occurs primarily via the JAK-STAT signaling pathway. Targeting this pathway through inhibition of activating cytokines (IL-4 and IL-13) and their receptors, the JAKs or the STATs, has been shown to have a therapeutic effect on asthma pathology. There are a number of novel drugs currently in development, which target various pathway components; these include both biologics and small molecules at various stages of development.

Acute nitrogen dioxide (NO2) exposure enhances airway inflammation via modulating Th1/Th2 differentiation and activating JAK-STAT pathway

Nitrogen dioxide (NO2) is an air pollutant associated with poor respiratory health, asthma exacerbation, and an increased likelihood of inhalational allergies. However, the underlying mechanisms are not clear. In the present study, the airway inflammatory response was first assessed in rats exposed to 5mg/m(3) NO2 for seven days. The results showed that NO2 exposure caused the pulmonary pathological alteration, and significantly stimulated MUC5AC expression. Following this, obviously up-regulated changes of pro-inflammatory cytokines (IL-1β, IL-6, and ICAM-1) were observed. Also, NO2 inhalation induced the imbalance in the ratio of Th1/Th2 differentiation (IL-4, IFN-γ, GATA-3 and T-bet) and the activation of following JAK-STAT pathway (JAK1, JAK3 and STAT6). The findings clarify an important mechanism for NO2 inhalation being injurious to the lung and augmenting the degree of allergic airway inflammation.

Acute high-level exposure to WTC particles alters expression of genes associated with oxidative stress and immune function in the lung

First responders (FR) present at Ground Zero in the first 72 h after the World Trade Center (WTC) collapsed have progressively exhibited significant respiratory injuries. The few toxicology studies performed to date evaluated effects from just fine (< 2.5 µm) WTC dusts; none examined health effects/toxicities from atmospheres bearing larger particle sizes, despite the fact the majority (> 96%) of dusts were > 10 µm and most FR likely entrained dusts by mouth breathing. Using a system that generated/delivered supercoarse (10-53 µm) WTC dusts to F344 rats (in a manner that mimicked FR exposures), this study sought to examine potential toxicities in the lungs. In this exploratory study, rats were exposed for 2 h to 100 mg WTC dust/m(3) (while under isoflurane [ISO] anesthesia) or an air/ISO mixture; this dose conservatively modeled likely exposures by mouth-breathing FR facing ≈750-1000 mg WTC dust/m(3). Lungs were harvested 2 h post-exposure and total RNA extracted for subsequent global gene expression analysis. Among the >  1000 genes affected by WTC dust (under ISO) or ISO alone, 166 were unique to the dust exposure. In many instances, genes maximally-induced by the WTC dust exposure (relative to in naïve rats) were unchanged/inhibited by ISO only; similarly, several genes maximally inhibited in WTC dust rats were largely induced/unchanged in rats that received ISO only. These outcomes reflect likely contrasting effects of ISO and the WTC dust on lung gene expression. Overall, the data show that lungs of rats exposed to WTC dust (under ISO) - after accounting for any impact from ISO alone - displayed increased expression of genes related to lung inflammation, oxidative stress, and cell cycle control, while several involved in anti-oxidant function were inhibited. These changes suggested acute inflammogenic effects and oxidative stress in the lungs of WTC dust-exposed rats. This study, thus, concludes that a single very high exposure to WTC dusts could potentially have adversely affected the respiratory system - in terms of early inflammatory and oxidative stress processes. As these changes were not compared with other types of dusts, the uniqueness of these WTC-mediated effects remains to be confirmed. It also still remains to be determined if these effects might have any relevance to chronic lung pathologies that became evident among FR who encountered the highest dust levels on September 11, 2001 and the 2 days thereafter. Ongoing studies using longer-range post-exposure analyses (up to 1-year or more) will help to determine if effects seen here on genes were acute, reversible, or persistent, and associated with corresponding histopathologic/biochemical changes in situ.

Pharmacophore and Virtual Screening of JAK3 inhibitors

Janus kinase 3 (JAK3) is a non-receptor tyrosine kinases family of protein which is comprised of JAK1, JAK2, JAK3 and TYK2. It plays an important role in immune function and lymphoid development and it only resides in the hematopoietic system. Therefore, selective targeting JAK3 is a rational approach in developing new therapeutic molecule. In this study, about 116 JAK3 inhibitors were collected from the literature and were used to build four-point pharmacophore model using Phase (Schrodinger module). The statistically significant pharmacophore hypothesis of AAHR.92 with r2 value of 0.942 was used as 3D query to search against 3D database namely Zincpharmer. A total of 2, 27,483 compounds obtained as hit were subjected to high throughput virtual screening (HTVS module of Schrodinger). Among the hits, ten compounds with good G-score ranging from -12.96 to -11.18 with good binding energy to JAK3 were identified.

JAK-1 rs2780895 C-related genotype and allele but not JAK-1 rs10789166, rs4916008, rs2780885, rs17127114, and rs3806277 are associated with higher susceptibility to asthma

BACKGROUND

Asthma, one major respiratory consequence, might be caused by a complex interaction between multiple candidate genes and environmental factors. Herein, we aimed to investigate whether Janus kinase (JAK)-1 gene polymorphisms are associated with asthma susceptibility.

MATERIALS AND METHODS

Patients were divided into two groups: (1) asthma (n=117) and (2) nonasthma (n=60). The JAK-1 polymorphisms (rs2780895, rs10789166, rs4916008, rs2780885, rs17127114, and rs3806277) were amplified by polymerase chain reaction and detected by electrophoresis after restriction enzyme (HpyCH4IV, Tsp45I, HpaII, XmnI, MspI, and HpaII) digestions. Genotypes, allelic frequencies, and association of haplotypes in both groups were compared.

RESULTS

JAK-1 rs2780895 gene polymorphism is associated with susceptibility to asthma. Distributions of JAK-1 rs2780895*CC/CT/TT and C/T allele in both groups are: (1) 80/4/16% and 82/18%; (2) 48/45/7% and 71/29%. Other 5 JAK-1 SNPs (rs10789166, rs4916008, rs2780885, rs17127114, and rs3806277) are not associated with asthma susceptibilities. Distributions of JAK-1 rs10789166*AA/AG/GG, rs4916008*CC/CT/TT, rs2780885*CC/CT/TT, rs17127114*AA/AG/GG, rs3806277*AA/AG/GG in both groups are: (1) 50/40/10%, 42/49/9%, 50/40/10%, 9/37/54%, 8/35/57%; (2) 43/50/7%, 40/50/10%, 50/43/7%, 7/48/45%, 6/42/52%. Haplotype analyses for JAK-1 gene polymorphisms (rs2780895-rs10789166-rs4916008-rs2780885-rs17127114-rs3806277) revealed that JAK-1 haplotypes are not associated with asthma susceptibilities.

CONCLUSIONS

JAK-1 rs2780895 C-related genotype and allele are associated with higher susceptibility to asthma. JAK-1 rs10789166, rs4916008, rs2780885, rs17127114, and rs3806277 single-nucleotide polymorphisms are not associated with asthma development. Some JAK-related genetic variations might be associated with asthma pathogenesis, which deserve further surveys.