Mast Cell Stabilizer Research Articles

Autonomic nervous system receptor-mediated regulation of mast cell degranulation modulates the inflammation after corneal epithelial abrasion

Mast cells (MCs) regulate wound healing and are influenced by the autonomic nervous system (ANS). However, the underlying mechanisms affecting wound healing outcomes remain elusive. Here, we explored the specific role of the ANS by regulating MC degranulation following corneal epithelium abrasion. A mouse model of corneal abrasion was established by mechanically removing a 2-mm central epithelium. Wound closure, neutrophil infiltration, and transcription of injured corneas were investigated using whole-mount immunostaining, flow cytometry, and RNA-sequencing analysis, respectively. Inhibition of MC degranulation by the MC stabilizers cromolyn sodium and lodoxamide tromethamine increased the infiltration of neutrophils and delayed healing of abraded corneas. Moreover, transcriptomic profiling analysis showed that purified MCs from the limbus expressed adrenergic and cholinergic receptors. Pharmacological manipulation and sympathectomy with 6-hydroxydopamine confirmed that sympathetic nervous system signaling inhibited MC degranulation after corneal abrasion, whereas parasympathetic nervous system signaling enhanced MC degranulation. We conclude that normal degranulation of MCs in the corneal limbus and crosstalk between the ANS and MCs are crucial for the appropriate control of inflammation and the repair progress of wounded corneas. This suggests a potential approach for improving defective corneal wound healing by the administration of clinically available autonomic activity-modulating agents.

Involvement of Polyamines From Cardiac Mast Cells in Myocardial Remodeling Induced by Pressure Overload Through Mitochondrial Permeability Transition Pore Opening.

ObjectivePolyamines mainly contain spermine (SPM), spermidine (SPD), and putrescine (PUT). Many research results suggest that polyamines participate in cell proliferation, differentiation, and the regulation of gene expression, and have a close relationship with the occurrence and development of many diseases. However, the role and possible mechanisms of action of polyamines from cardiac mast cells in myocardial remodeling induced by pressure overload remain to be elucidated.MethodsPressure overload was induced by abdominal aortic constriction (AAC). Toluidine blue staining was used to visualize mast cells in cardiac tissue. The polyamine content of cardiac tissue was analyzed using high-performance liquid chromatography. Opening of the mitochondrial permeability transition pore (MPTP) was determined by the Ca2+-induced swelling of isolated cardiac mitochondria, measured as a reduction in A520.ResultsCompared with sham rats, the cardiac mast cell density, the polyamine content (PUT, SPB, and SPM), and myocardial MPTP opening in rats with AAC were significantly increased (P < 0.05), and were accompanied by increased myocardial fibrosis and heart weight/body weight ratio. Intraperitoneal injection of polyamines mimicked these results, and these effects were reversed by cromolyn sodium, a mast cell stabilizer (P < 0.05). Myocardial MPTP opening increased in rats with AAC (P < 0.05), and the three polyamines also increased myocardial MPTP opening (P < 0.05).ConclusionMast cell-derived polyamines are involved in pressure overload-induced myocardial remodeling by increasing opening of the MPTP.

Efficacy of N-acetyl aspartyl glutamic acid versus fluorometholone for treating allergic conjunctivitis in an environmental exposure chamber.

BackgroundTopical mast cell stabilizers were previously shown to treat the signs and symptoms of seasonal and perennial allergic conjunctivitis safely and effectively in active and placebo‐controlled trials. However, mast cell stabilizers have not been compared to topical corticosteroids for efficacy. We tested the non‐inferiority of a topical mast cell stabilizer, N‐acetyl aspartyl glutamic acid (4.9%, NAAGA), compared to fluorometholone (0.1%, FM) during controlled exposures to the airborne birch pollen allergen, Bet v 1, in an environmental exposure chamber (EEC).MethodsThis randomized, cross‐over, investigator‐blinded study included 24 patients with a history of birch pollen allergic conjunctivitis. Patients were randomized to 5 days of treatment with NAAGA, then FM (n = 12) or FM, then NAAGA (n = 12). After each treatment, patients were exposed to a fixed airborne concentration of Bet v 1 in ALYATEC EEC. The primary endpoint was the amount of allergen required to trigger a conjunctival response (Abelson score ≥5). Groups were compared with a linear model for cross‐over studies. Non‐inferiority was assumed, when the lower bound of the risk ratio confidence interval (CI) was >0.5.ResultsAt screening, the mean time‐to‐conjunctival response was 72.5 ± 35.9 min. NAAGA and FM extended the response time to 114.8 ± 55.0 and 116.6 ± 51.5 min respectively. The mean amounts of allergen required to trigger a conjunctival response were 1.165 ng after NAAGA and 1.193 ng after FM treatment. The risk ratio for the conjunctival response was 0.977 (95% CI: 0.812; 1.174), which indicated non‐inferiority. Adverse events occurred less frequently with NAAGA (29.2%) than with FM (58.3%).ConclusionIn patients with allergic conjunctivitis to birch pollen, NAAGA was non‐inferior to FM in exposures to airborne Bet v 1. The EEC was a good model for simulating real‐life airborne allergen exposure and for demonstrating the efficacy and safety of eye drops for treating allergic conjunctivitis.Trial registrationNot registered.

Lirentelimab for severe and chronic forms of allergic conjunctivitis

Allergic conjunctivitis (AC) is an ocular inflammatory disease with symptoms driven by eosinophils and mast cells. Allergic comorbidities are common. Current treatments are often ineffective in severe AC and limited by potential side effects. Lirentelimab is an anti-sialic acid-binding immunoglobulin-like lectin-8 mAb that depletes eosinophils and inhibits mast cells. We sought to determine safety and preliminary efficacy of lirentelimab in an open-label, phase 1b study. Patients with chronic, severely symptomatic atopic keratoconjunctivitis, vernal keratoconjunctivitis, and perennial AC, and who had history of topical or systemic corticosteroid use, were enrolled to receive up to 6 monthly lirentelimab infusions (dose 1: 0.3 mg/kg, dose 2: 1 mg/kg, subsequent doses: 1 or 3 mg/kg). Changes from baseline in peripheral blood eosinophils, changes in patient-reported symptoms (measured by daily Allergic Conjunctivitis Symptom Questionnaire, including atopic comorbidities), changes in investigator-reported ocular signs and symptoms (Ocular Symptom Scores), changes in quality of life, and changes in tear cytokine and chemokine levels were assessed. Thirty patients were enrolled (atopic keratoconjunctivitis n= 13, vernal keratoconjunctivitis n= 1, perennial AC n= 16), 87% of whom had atopic comorbidities. After lirentelimab treatment, mean improvement was observed in Allergic Conjunctivitis Symptom Questionnaire score (-61%; 95% CI, -75% to -48%) and Ocular Symptom Scores (-53%; 95% CI, -76% to -31%), consistent across atopic keratoconjunctivitis, vernal keratoconjunctivitis, and perennial AC groups. There was substantial improvement in atopic comorbidities, with -55% (95% CI, -78% to -31%), -50% (95% CI, -82% to -19%), and -63% (95% CI, -87% and -38%) reduction in symptoms of atopic dermatitis, asthma, and rhinitis, respectively. Levels of key mediators of inflammation were reduced in patient tears after lirentelimab treatment. The most common adverse effects were mild to moderate infusion-related reactions. Lirentelimab was well tolerated, improved severe AC and concomitant atopic symptoms, and reduced inflammatory mediators in patient tears.

Menthone Inhalation Alleviates Local and Systemic Allergic Inflammation in Ovalbumin-Sensitized and Challenged Asthmatic Mice.

Menthone is rich in Mentha × Piperita L. essential oil and it has anti-inflammatory properties; research shows that it is useful, via percutaneous absorption, in treating inflammation-related diseases. However, anti-allergic inflammatory effects of volatile menthone have not yet been used to treat allergic asthma, in vivo. We hypothesized that menthone inhalation may have anti-inflammatory and anti-allergic effects in patients with allergic asthma. Therefore, in our study, menthone inhalation was used to treat ovalbumin (OVA)-sensitized and challenged asthmatic mice. Allergic inflammation mediator changes in the lungs and airways, sera, splenocytes, and peritoneal macrophages of the mice were measured. Relative expression amounts of six receptor genes related to allergic inflammation of the lungs and airways were quantitated using a two-step real time quantitative polymerase chain reaction (qPCR). Results showed that menthone inhalation increased serum OVA-specific IgG2a/IgG1 and IgG2a/IgE ratios, increased Th1-type cytokine production in the bronchoalveolar lavage fluid, and decreased nitric oxide, protein, and eotaxin levels. Menthone inhalation inhibited mast cell and eosinophil degranulation, and chemokine (C-C motif) receptor 3 (Ccr3) gene expression amounts, but (relatively) increased Th1 cytokine secretion by splenocytes. Our results evidence that menthone inhalation alleviates local and systemic allergic inflammation in asthmatic mice.

In Vitro Antioxidant and Mast Cell Stabilizing Activity of Different Extracts of Vanda Spathulata Flowers

Objective: The objective of the present work is to evaluate the petroleum ether, ethyl acetate and methanolic extracts of vanda spathulata on experimental models for in vitro antioxidant activity and mast cell stabilizing activity. Methods: Mast cell stabilization effect was assessed using compound 48/80 induced mast cell degranulation in rat peritoneal mast cell. The antioxidant activity was evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Results and Discussion: Vanda spathulata methanolic extract (VSME) at doses of 200 and 400mg/kg exhibited significant protection (p&lt;0.01) and petroleum ether (VSPE) and ethylacetate (VSEA) extracts at the dose of 400mg/kg showed significant protection (p&lt;0.05) against mast cell degranulation. VSME revealed better DPPH radical scavenging activity (IC50 value 38.39 µg/ml) which was closely resembled to standard ascorbic acid (IC50 value 33.98 µg/ml) when compared to other extracts. Phytochemical study revealed the presence of alkaloids, saponins, flavonoids, tannins, steroids and glycosides. Conclusion: From the results Vanda spathulata shows mast cell stabilizing activity mainly due to phytochemical constituents and strong antioxidant property of plant extracts.

Clinical effectiveness and local side effects of topical 0.05% cyclosporine in treatment of children with severe vernal keratoconjunctivitis

Purpose: To evaluate the therapeutic response of topical cyclosporine (CyS-A) in patients with vernal keratoconjunctivitis (VKC), resistant to topical mast cell stabilizer (MCS) and anti-histamine therapy. Study Design: Quasi experimental study. Place and Duration of Study: Qazi Hussain Ahmad Medical Complex, Nowshera, from April 2019 to August 2019. Methods: Forty patients, 30 males and 10 females, less than 18 years of age and diagnosed with Vernal Keratoconjunctivitis were enrolled in the study. All participants were graded based upon severity of the disease at presentation with a score of 0 for normal, 1 for mild, 2 for moderate and 3 for severe, for both symptoms and signs. Each patient received topical CyS-A 0.05%in QID regimen in addition to lubricating tear substitute. Followup was done for 04 months. Results: Clinical scoring was done at baseline and at the 1st, 2nd and 4th month following therapy. After 4 months of topical application, not only the patients improved symptomatically but their clinical signs also improved, which achieved a level of statistical significance (p &lt; 0.05). All participants completed the follow-up duration of therapy. Although Horner Tranta’s dot showed improvement, but comparison of baseline with 1st month values were statistically non-significant (p = 0.048). However, during 2nd and 4th month, the improvement achieved statistical significance (p = 0.013 and p = 0.006 respectively). None of the participants reported any bothersome local side effect. Conclusion: Topical cyclosporine 0.05% is effective in alleviating the symptoms and signs without any local side effects in resistant VKC. Key Words: Vernal keratoconjunctivitis, Cyclosporine, Cobblestone Papillae.

Relationship between allergic rhinitis and allergic conjunctivitis (allergic rhinoconjunctivitis) - review.

Allergic rhinitis and allergic conjunctivitis are so frequently associated that the need to coin a new name to describe the simultaneous manifestations generated the term allergic rhinoconjunctivitis. The significant impact of rhinoconjunctivitis on the quality of life and the wellbeing of the patients is the reason why the medical community shows a great interest to this disease. Another aspect is the financial burden that is not negligible. The anatomical connection between the organs involved facilitates the propagation of the disease. The allergic pathophysiological mechanisms implicated in allergic rhinitis and conjunctivitis also share common features. The diagnosis of rhinoconjunctivitis is based on the concordance between the symptoms, the clinical examination, and the diagnostic tests that should reveal the existence of an allergen specific IgE in vivo or in vitro. Whilst the nasal smear for eosinophils is considered a reliable diagnostic test for allergic rhinitis, the occurrence of eosinophils in the conjunctive is not a trustworthy indicator of allergy. The therapy of allergic rhinoconjunctivitis is based on patient education, pharmacotherapy, and allergen-specific immunotherapy. The local treatment for the allergic rhinitis is primarily based on topical corticosteroids that also manage the ocular symptoms. The first line of treatment of the ocular manifestations is represented by topical antihistamines and mast-cell stabilizers or double action drugs.

Inhibitory Effect of Rhododendron Mucronulatum Root Extract on Allergic Inflammation

Objective: In this study, we investigated the protective effect of rhododendron mucronulatum extract (RME) on allergic reactions and inflammation.Methods: The effect of RME was determined using ELISA and RT-PCR in RBL-2H3 mast cells and RAW 264.7 macrophage cells. We determined cell viability, β-hexosaminidase release, and the synthesis of IL-4 and TNF-α in RBL-2H3 cells. In addition, we determined NO from RAW 264.7 and the gene expression of IL-1β, iNOS, IL-6, TNF-α, and IL-10.Results: RME inhibited β-hexosaminidase release and synthesis of IL-4 and TNF-α in RBL-2H3 by the anti-DNP IgE plus DNP-HSA stimulation. In addition, RME inhibited the production of NO and the gene expression of IL-1β, iNOS, IL-6, and TNF-α in LPS-stimulated RAW 264.7 cells.Conclusion: From these results, we concluded that RME possesses anti-allergic activity and anti-inflammatory activity due to the inhibition of mast cells and macrophage function.

Early life adversity drives sex-specific anhedonia and meningeal immune gene expression through mast cell activation

Exposure to early life adversity (ELA) in the form of physical and/or psychological abuse or neglect increases the risk of developing psychiatric and inflammatory disorders later in life. It has been hypothesized that exposure to ELA results in persistent, low grade inflammation that leads to increased disease susceptibility by amplifying the crosstalk between stress-processing brain networks and the immune system, but the mechanisms remain largely unexplored. The meninges, a layer of three overlapping membranes that surround the central nervous system (CNS)- dura mater, arachnoid, and piamater – possess unique features that allow them to play a key role in coordinating immune trafficking between the brain and the peripheral immune system. These include a network of lymphatic vessels that carry cerebrospinal fluid from the brain to the deep cervical lymph nodes, fenestrated blood vessels that allow the passage of molecules from blood to the CNS, and a rich population of resident mast cells, master regulators of the immune system. Using a mouse model of ELA consisting of neonatal maternal separation plus early weaning (NMSEW), we sought to explore the effects of ELA on sucrose preference behavior, dura mater expression of inflammatory markers and mast cell histology in adult male and female C57Bl/6 mice. We found that NMSEW alone does not affect sucrose preference behavior in males or females, but it increases the dura mater expression of the genes coding for mast cell protease CMA1 (cma1) and the inflammatory cytokine TNF alpha (tnf alpha) in females. When NMSEW is combined with an adult mild stress (that does not affect behavior or gene expression in NH animals) females show reduced sucrose preference and even greater increases in meningeal cma1 levels. Interestingly, systemic administration of the mast cell stabilizer Ketotifen before exposure to adult stress prevents both, reduction in sucrose preference an increases in cma1 expression in NMSEW females, but facilitates stress-induced sucrose anhedonia in NMSEW males and NH females. Finally, histological analyses showed that, compared to males, females have increased baseline activation levels of mast cells located in the transverse sinus of the dura mater, where the meningeal lymphatics run along, and that, in males and females exposed to adult stress, NMSEW increases the number of mast cells in the interparietal region of the dura mater and the levels of mast cell activation in the sagittal sinus regions of the dura mater. Together, our results indicate that ELA induces long-term meningeal immune gene changes and heightened sensitivity to adult stress-induced behavioral and meningeal immune responses and that these effects could mediated via mast cells.

Mast cell mediation of visceral sensation and permeability in irritable bowel syndrome.

Abnormalities of mast cell structure or function may play prominent roles in irritable bowel syndrome (IBS) symptom genesis. Mast cells show close apposition to sensory nerves and release bioactive substances in response to varied stimuli including infection, stress, and other neuroendocrine factors. Most studies focus on patients who develop IBS after enteric infection or who report diarrhea‐predominant symptoms. Three topics underlying IBS pathogenesis have been emphasized in recent investigations. Visceral hypersensitivity to luminal stimulation is found in most IBS patients and may contribute to abdominal pain. Mast cell dysfunction also may disrupt epithelial barrier function which alters mucosal permeability potentially leading to altered bowel function and pain. Mast cell products including histamine, proteases, prostaglandins, and cytokines may participate in hypersensitivity and permeability defects, especially with diarrhea‐predominant IBS. Recent experimental evidence indicates that the pronociceptive effects of histamine and proteases are mediated by the generation of prostaglandins in the mast cell. Enteric microbiome interactions including increased mucosal bacterial translocation may activate mast cells to elicit inflammatory responses underlying some of these pathogenic effects. Therapies to alter mast cell activity (mast cell stabilizers) or function (histamine antagonists) have shown modest benefits in IBS. Future investigations will seek to define patient subsets with greater potential to respond to therapies that address visceral hypersensitivity, epithelial permeability defects, and microbiome alterations secondary to mast cell dysfunction in IBS.

Fructus Amomi extract attenuates nasal inflammation by restoring Th1/Th2 balance and down-regulation of NF-κB phosphorylation in OVA-induced allergic rhinitis.

Fructus Amomi Cardamomi (FA) is the mature fruit of Amomum villosum Lour (family Zingiberaceae) and is commonly used in Chinese traditional medicine to treat various gastrointestinal disorders. FA’s possible benefits as an allergic rhinitis (AR) treatment, however, have not been examined. We used an ovalbumin (OVA)-induced AR mouse model to identify any anti-allergic effects associated with the administration of 200 mg/kg FA or dexamethasone (Dex) 2.5 mg/kg by oral administration. The results of our testing confirm that FA ameliorated nasal symptoms and alleviated nasal epithelium swelling, reduced the goblet cell hyperplasia and eosinophil cell infiltration in the nasal epithelium, and inhibited lung tissue inflammation and Dex as well. Significantly decreased Th2 cytokine (interleukin (IL)-1β, IL-4, and IL-5) expression, and a correspondingly significant increase in Th1 cytokine (IL-12, interferon (IFN)-γ) production, was observed in nasal lavage fluid (NALF) taken from mice that received FA or Dex treatment. FA also reduced the presence of OVA-specific immunoglobulin (Ig) E, OVA-specific IgG1, and histamine levels in serum, and inhibited mast cell degranulation in vitro. In addition, these effects were involved with the reduction in NF-κB phosphorylation. These results suggest that FA restores Th1/Th2 balance and inhibits NF-κB phosphorylation and mast cell degranulation, thereby achieving a notable anti-inflammatory effect. Accordingly, it has the potential to be used as an efficacious therapeutic treatment for AR.

A Quality by Design and green LC technique for the determination of mast cell stabilizer and histamine receptor antagonist (Olopatadine HCl) in multiple formulations.

Mast cell stabilizer and histamine receptor antagonist olopatadine hydrochloride (OPT) assay method predicated on LC have been established for the analysis in multiple formulations. The current method dealt with ophthalmic solution, nasal spray, and tablet formulation products. The isocratic chromatography method was optimized and validated with a Boston green C8 column (150 × 4.6 mm, 5μm i.d.). Sodium dihydrogen phosphate buffer (pH3.5) with acetonitrile in the ratio of 75:25 (v/v) was used as a mobile phase at a flow rate of 1.0mL min-1 and at the column temperature of 30°C, and the detection was done at 299 nm. The method was validated as per International Council for Harmonisation (ICH) guidelines and United States Pharmacopoeia (USP). The accuracy results ranged from 99.9 to 100.7%, % relative standard deviation (RSD) from the precision was 0.5, and correlation coefficient from the linearity experiment was > 0.999. Solution stability was established for 24 h at room temperature and refrigerator conditions, and it was found that the solutions were stable. Using quality by design-based experiment designs, critical quality attributes were studied and it was found that the method was robust. In all the forced degradation studies peak purity was passed, and no interference was found at the retention time of the active component. The method validation data demonstrated that the developed method is linear, precise, accurate, specific, robust, and stable for the determination of OPT from multiple formulations. Analytical eco-scale tool, Green Analytical Procedure Index (GAPI) tool, and the National Environmental Method Index (NEMI) were used to evaluate the greenness of the method, and the analytical eco-score of 77 for the presented method was found to be excellent.

Small extracellular vesicles from iPSC-derived mesenchymal stem cells ameliorate tendinopathy pain by inhibiting mast cell activation.

Aim: This study aimed to explore the effect of small extracellular vesicles from induced pluripotent stem cell-derived mesenchymal stem cells (iMSC-sEVs) on acute pain and investigate the underlying mechanisms. Materials & methods: The pathology of tendons was accessed by hematoxylin and eosin staining, immunohistochemical and immunofluorescent staining. The pain degree was measured by pain-related behaviors. In vitro, we performed β-hexosaminidase release assay, RT-qPCR, toluidine blue staining, ELISA and RNA sequencing. Results: iMSC-sEVs effectively alleviated acute pain in tendinopathy as well as inhibiting activated mast cell infiltration and interactions with nerve fibers in vivo. In vitro, iMSC-sEVs reduced the degranulation of mast cells and the expression of proinflammatory cytokines and genes involved in the HIF-1 signaling pathway. Conclusion: This study demonstrated that iMSC-sEVs relieved tendinopathy-related pain through inhibiting mast cell activation via the HIF-1 signaling pathway.

A Comparative Study of Olopatadine Hydrochloride and Bepotastine Besilate in the Treatment of Allergic Conjunctivitis

Background -Ocular allergy is a commonly encountered pathology in clinical practice, which often is under diagnosed and consequently undertreated. These are rarely vision-threatening but can significantly decrease the quality of life for patients. Olopatadine and Bepotastine eyedrop have both antihistaminic and mast cell stabilization action. Their use can control acute symptoms and prevent relapses as well. We conducted this single blinded trial directly comparing the efficacy of the two topical anti allergic medications in mild forms of allergic conjunctivitis. Materials and Methods - A single blinded randomised control clinical trial study was conducted in patients visiting OPD of Ophthalmology at the institute for duration of 6 months. All the patients above 18 years of age having mild to moderate allergic conjunctivitis were included in the study. Patients were randomly placed in one of the two groups according to computer generated random numbers and given topical anti-allergic medication for twice daily. Group A was given Topical 0.1% Olopatadine eye drops BD and Group B was given Topical 1.5% Bepotastine eye drops BD. Ophthalmological check-up was done using slit lamp on next day, after 1 week, after 21-28 days. Results - It was seen from the study that on follow up day 1 in patients receiving Bepotastine 1.5% eyedrop, there was 50% relief of symptoms and signs seen in 80% patients while in 60% patients, only 40% relief in symptoms and sign was seen with olopatadine 0.1% eyedrop. On follow up day 7, 90% of symptoms and signs of allergic conjunctivitis were relieved in all patients receiving Bepotastine eyedrop while 80% relief was seen in those receiving olopatadine. Almost 100% relief from signs and symptoms were seen in both the groups on follow up day 21-28th. Conclusion- We conclude from our study that, Bepotastine besilate 1.5% ophthalmic solution is a preferred drug compared to Olopatadine 0.1% in the immediate relief of symptoms and signs of allergic conjunctivitis. It can be used as an initial therapy in the symptom relief and alternative to the topical steroids used in mild-moderate allergic conjunctivitis. Keywords: Allergic conjunctivitis, Ocular allergy, Olopatadine hydrochloride, Bepotastine besilate.

Cromolyn Sodium differentially regulates human mast cell and mouse leukocyte responses to control allergic inflammation

BackgroundCromolyn Sodium (CS) has been used in the past as an anti-allergy drug owing to its mast cell (MC) stabilizing properties that impair histamine release. However, additional mechanisms for its clinical actions are likely and might help to identify new roles for MCs and leukocytes in regulating inflammation. Here, using human cord blood-derived MCs (CBMCs), mouse bone marrow-derived MCs (BMMCs) and eosinophils (BMEos), and in vivo mouse models of allergic inflammation (AI), additional actions of CS on MCs were determined. MethodsThe in vitro effects of CS on IgE-activated human and mouse MCs were assessed by measuring the levels of pro-inflammatory (tryptase, LTC4, IL-8, CD48) and pro-resolution effectors (IL-10, CD300a, Annexin A1) before and after CS treatment. The in vivo effects of daily CS injections on parameters of inflammation were assessed using mouse models of allergic peritonitis (AP) (Ovalbumin/Alum- or Ovalbumin/S. aureus enterotoxin B) and allergic airways inflammation (AAI) (house dust mite (HDM)). ResultsIn vitro, CS did not affect pro-inflammatory effectors but significantly increased the anti-inflammatory/pro-resolution CD300a levels and IL-10 release from IgE-activated CBMCs. BMMCs were not affected by CS. In vivo, CS injections decreased total cell and Eos numbers in the peritoneal cavity in the AP models and bronchoalveolar lavage and lungs in the AAI model. CS reduced EPX release from PAF-activated BMEos in vitro, possibly explaining the in vivo findings. ConclusionTogether, these results demonstrate immunomodulatory actions for CS in AI that are broader than only MC stabilization.

An in vivo rabbit joint injury model to measure trauma-induced coagulopathy and the effect of timing of administration of ketotifen fumarate on posttraumatic joint contracture.

Objectives:Using a rabbit in vivo joint injury model, the primary objective of the study was to determine if a relationship exists between earlier time to initiation of ketotifen fumarate (KF) treatment and posttraumatic joint contracture (PTJC) reduction. The secondary objective was to determine if a coagulation response could be detected with serial thrombelastography (TEG) analysis following acute trauma in this model.Methods:PTJC of the knee were created in 25 skeletally mature, New Zealand White rabbits. Five groups of 5 animals were studied: a control group that received twice daily subcutaneous injections of normal saline and 4 treatment groups that received twice daily subcutaneous injections of KF (0.5 mg/kg) starting immediately, 1-, 2-, and 4-weeks post-injury. After 8 weeks of immobilization, flexion contractures were measured biomechanically. Serial TEG analysis was performed on the control group animals pre-injury and weekly post-injury.Results:The average joint contracture in the Control Group (43.1° ± 16.2°) was higher than all KF treatment groups; however, the differences were not statistically significant. The average joint contracture was lowest in the 2-week post-injury treatment group (29.4° ± 12.1°), although not statistically significant compared to the other treatment groups. Serial TEG analysis demonstrated significantly higher mean maximal amplitude (maximal amplitude = 68.9 ± 1.7 mm; P < .001), alpha-angle (81.9° ± 0.9°; P < .001), and coagulation index (4.5 ± 0.3; P < .001) 1-week post-injury, which normalized to pre-injury values by 5-weeks post-injury.Conclusions:The use of the mast cell stabilizer KF within 2 weeks of injury demonstrated a nonsignificant trend towards reducing joint contracture in a rabbit in vivo model of PTJC. TEG and the in vivo rabbit joint injury model may be valuable in future preclinical studies of venous thromboembolism prevention and furthering our understanding of the pathophysiology of posttraumatic hypercoagulability.

Aktivitas Ramuan Herbal sebagai Antagonis Reseptor H1, Relaksan Otot Polos dan Penghambat Degranulasi Sel Mast sebagai Antiasmatik

Asthma is still become a major health problem worldwide, affected all ages from pediatrics to &#x0D; adults. The severity of the disease vary from mild to severe and leads to the risk of death. The &#x0D; uses of medicinal plants as antiasthmatic have often been conducted by the local community. &#x0D; The present study was conducted in vitro and in vivo to determine the activities of herbs &#x0D; containing of sembung leaves (Blumea balsamifera L.), kemukus seeds (Piper cubeba L.), teki &#x0D; rhizome (Cyperus rotundus L.), and patikan kebo herbs (Euphorbia hirta L.) with certain ratio &#x0D; as an antiasthmatic. The in vitro test was carried out on isolated smooth muscle cells of guinea &#x0D; pig. Histamine was used to stimulate the contraction of smooth muscle cells of guinea pig &#x0D; trachea. The in vivo test was carried out using guinea pigs which sensitized with ovalbumin &#x0D; and administered with the herbs formula. The trachea of guinea pigs were prepared for &#x0D; histopathological examination and stained on toluidine blue. The result revealed that the &#x0D; antiasthmatic herbs of 1, 2, and 3 showed activities as H1 receptor antagonists. The &#x0D; antiasthmatic herbs of 1, 2, and 3 were able to relax the smooth muscle of guinea pig’s trachea &#x0D; that was experiencing contraction, but in lower level compared to theophylline. The&#x0D; antiasthmatic herbs formula in this study did not have the activity to inhibit mast cell &#x0D; degranulation.

Mesenchymal stem cell therapy for alleviating ocular surface inflammation in allergic conjunctivitis

Allergic eye diseases have become a major concern worldwide, especially in the paediatric population. Vernal keratoconjunctivitis, a seasonal, chronic, bilateral inflammation of the ocular surface, represents one of the most common forms of ocular allergy in subtropical climates which may lead to corneal scarring and blindness if not properly treated. Late diagnosis of the disease and potential side effects of the currently used topical steroids, antihistamines, and mast cell stabilizers necessitates the development of early diagnostic tools and alternate immunosuppressive therapies. Mesenchymal stem cells have shown promising therapeutic potentials due to their tissue repair, anti-allergic, and immunomodulatory properties. However, their role in allergic conjunctivitis/vernal keratoconjunctivitis is poorly explored. Here, it is hypothesized that mesenchymal stem cells or their secreted products alleviate inflammation and promote repair of the damaged ocular surface in allergic conjunctivitis patients. It is presumed that they do so through multiple anti-allergic mechanisms and maintain long-term immunosuppression with significantly reduced or negligible side effects. These cells or their secreted products (extracellular vesicles, growth factors, conditioned medium, inflammatory mediators, and other biomolecules) can be used as topical immunosuppressive medications for effectively treating ocular surface inflammation in allergic conjunctivitis.

The Multifaceted Roles of Mast Cells in Immune Homeostasis, Infections and Cancers.

Mast cells (MCs) play important roles in normal immune responses and pathological states. The location of MCs on the boundaries between tissues and the external environment, including gut mucosal surfaces, lungs, skin, and around blood vessels, suggests a multitude of immunological functions. Thus, MCs are pivotal for host defense against different antigens, including allergens and microbial pathogens. MCs can produce and respond to physiological mediators and chemokines to modulate inflammation. As long-lived, tissue-resident cells, MCs indeed mediate acute inflammatory responses such as those evident in allergic reactions. Furthermore, MCs participate in innate and adaptive immune responses to bacteria, viruses, fungi, and parasites. The control of MC activation or stabilization is a powerful tool in regulating tissue homeostasis and pathogen clearance. Moreover, MCs contribute to maintaining the homeostatic equilibrium between host and resident microbiota, and they engage in crosstalk between the resident and recruited hematopoietic cells. In this review, we provide a comprehensive overview of the functions of MCs in health and disease. Further, we discuss how mouse models of MC deficiency have become useful tools for establishing MCs as a potential cellular target for treating inflammatory disorders.