Carbonic anhydrase enzymes regulate mast cell-mediated inflammation

Modulation of haematopoiesis by protozoal and helminth parasites

During inflammation, haematopoietic stem cells (HSCs) in the bone marrow (BM) and periphery rapidly expand and preferentially differentiate into myeloid cells that mediate innate immune responses. HSCs can be directed into quiescence or differentiation by sensing alterations to the haematopoietic niche, including cytokines, chemokines, and pathogen-derived products. Most studies attempting to identify the mechanisms of haematopoiesis have focused on bacterial and viral infections. From intracellular protozoan infections to large multicellular worms, parasites are a global health burden and represent major immunological challenges that remain poorly defined in the context of haematopoiesis. Immune responses to parasites vary drastically, and parasites have developed sophisticated immunomodulatory mechanisms that allow development of chronic infections. Recent advances in imaging, genomic sequencing, and mouse models have shed new light on how parasites induce unique forms of emergency haematopoiesis. In addition, parasites can modify the haematopoiesis in the BM and periphery to improve their survival in the host. Parasites can also induce long-lasting modifications to HSCs, altering future immune responses to infection, inflammation or transplantation, a term sometimes referred to as central trained immunity. In this review, we highlight the current understanding of parasite-induced haematopoiesis and how parasites target this process to promote chronic infections.

Communication is key: Innate immune cells regulate host protection to helminths

Parasitic helminth infections remain a significant global health issue and are responsible for devastating morbidity and economic hardships. During infection, helminths migrate through different host organs, which results in substantial tissue damage and the release of diverse effector molecules by both hematopoietic and non-hematopoietic cells. Thus, host protective responses to helminths must initiate mechanisms that help to promote worm clearance while simultaneously mitigating tissue injury. The specialized immunity that promotes these responses is termed type 2 inflammation and is initiated by the recruitment and activation of hematopoietic stem/progenitor cells, mast cells, basophils, eosinophils, dendritic cells, neutrophils, macrophages, myeloid-derived suppressor cells, and group 2 innate lymphoid cells. Recent work has also revealed the importance of neuron-derived signals in regulating type 2 inflammation and antihelminth immunity. These studies suggest that multiple body systems coordinate to promote optimal outcomes post-infection. In this review, we will describe the innate immune events that direct the scope and intensity of antihelminth immunity. Further, we will highlight the recent progress made in our understanding of the neuro-immune interactions that regulate these pathways and discuss the conceptual advances they promote.

Mechanisms of pulmonary vascular dysfunction in pulmonary hypertension and implications for novel therapies

Pulmonary hypertension (PH) is a serious disease characterized by various degrees of pulmonary vasoconstriction and progressive fibroproliferative remodeling and inflammation of the pulmonary arterioles that lead to increased pulmonary vascular resistance, right ventricular hypertrophy, and failure. Pulmonary vascular tone is regulated by a balance between vasoconstrictor and vasodilator mediators, and a shift in this balance to vasoconstriction is an important component of PH pathology, Therefore, the mainstay of current pharmacological therapies centers on pulmonary vasodilation methodologies that either enhance vasodilator mechanisms such as the NO-cGMP and prostacyclin-cAMP pathways and/or inhibit vasoconstrictor mechanisms such as the endothelin-1, cytosolic Ca2+, and Rho-kinase pathways. However, in addition to the increased vascular tone, many patients have a "fixed" component in their disease that involves altered biology of various cells in the pulmonary vascular wall, excessive pulmonary artery remodeling, and perivascular fibrosis and inflammation. Pulmonary arterial smooth muscle cell (PASMC) phenotypic switch from a contractile to a synthetic and proliferative phenotype is an important factor in pulmonary artery remodeling. Although current vasodilator therapies also have some antiproliferative effects on PASMCs, they are not universally successful in halting PH progression and increasing survival. Mild acidification and other novel approaches that aim to reverse the resident pulmonary vascular pathology and structural remodeling and restore a contractile PASMC phenotype could ameliorate vascular remodeling and enhance the responsiveness of PH to vasodilator therapies.

Identification of early response to hypertonic dextrose prolotherapy markers in knee osteoarthritis patients by an inflammation-related cytokine array

BACKGROUND

Osteoarthritis (OA) is one of the most common forms of arthritis, and hypertonic dextrose prolotherapy has long been used clinically to treat knee OA. The aim of this study was to investigate the inflammation-related protein-expression profile characterizing the efficacy of the hypertonic dextrose prolotherapy in knee OA as prognostic markers.

METHODS

OA patients over the age of 65 were recruited for Western Ontario McMaster University Osteoarthritis (WOMAC) index, knee X-ray evaluation and knee joint synovial fluid analysis before and after hypertonic dextrose prolotherapy. The expressions of inflammation-related factors were measured using a novel cytokine antibody array methodology. The cytokine levels were quantified by quantitative protein expression and analyzed by ELISA using the patients' knee-joint synovial fluid.

RESULTS

The WOMAC Index and minimum joint space width before receiving the intra-articular injection and at 2-week intervals were compared. Twelve patients who received OA intervention were enrolled and finally a clinical evaluation of 12 knee joints and knee synovial fluid samples were analyzed. In this study, after receiving hypertonic dextrose prolotherapy, the OA patients clearly demonstrated a significant improvement in WOMAC index and increasing tendency in the medial minimum joint space width after intervention. Meanwhile, we observed a significantly associated tendency between hypertonic dextrose treatment of knee OA and the upregulation of MMP2, TIMP-1, EGF, CXCL9 and IL-22.

CONCLUSION

The findings provide knee OA patients receiving hypertonic dextrose prolotherapy, which is accompained by the improvemeny of knee symptoms and associated tendency of upregulation of MMP2, EGF, CXCL 9 and IL-22.

In vitro and In silico Interactions of Antiulcer, Glucocorticoids and Urological Drugs on Human Carbonic Anhydrase I and II isozymes

Carbonic anhydrases (CAs, EC 4.2.1.1) convert carbon dioxide to bicarbonate in metabolism and use Zn²⁺ ions as a cofactor for their catalytic activity. The activators or inhibitors of CA-I and CA-II, which are the most abundant CA isozymes in erythrocytes, have pharmacological applications in medicine. So, investigation of drug-protein interaction of these isozymes is significant. On this basis, the objective of this study was to clarify the primer effects of widely used drugs on the activity of human CA-I and CA-II enzymes and elucidate the inhibition mechanism through molecular docking studies. For this aim isozymes were purified from human erythrocytes by affinity chromatography technique. Then inhibition profiles of antiulcer, glucocorticoids, and urological drugs were investigated. As a result, while budesonide had the highest inhibitory potency on hydratase activity of hCA-I with the IC₅₀ of 0.08 mM, levofloxacin showed the highest inhibition effect on hCA-II with the IC₅₀ of 0.886 mM. The most effective inhibitor on the esterase activity of isozymes was found as fluticasone propionate with the K_i values of 0.0365±0.016 mM and 0.054±0.018 mM respectively. However, by molecular docking study, it was estimated that budesonide showed maximum inhibition potency for both isozymes with the free binding energy of -7.58 and -6.97 kcal/mol respectively. Consequently, it was observed that some of the drugs studied did not show any inhibitory effect. Drug-enzyme interactions were also estimated by molecular docking. This study could contribute to the discovery of new drug candidates and as well as target proteins. This article is protected by copyright. All rights reserved.

Carbonic Anhydrase IV Selective Inhibitors Counteract the Development of Colitis-Associated Visceral Pain in Rats

Persistent pain affecting patients with inflammatory bowel diseases (IBDs) is still very difficult to treat. Carbonic anhydrase (CA) represents an intriguing pharmacological target considering the anti-hyperalgesic efficacy displayed by CA inhibitors in both inflammatory and neuropathic pain models. The aim of this work was to evaluate the effect of inhibiting CA IV, particularly when expressed in the gut, on visceral pain associated with colitis induced by 2,4-di-nitrobenzene sulfonic acid (DNBS) in rats. Visceral sensitivity was assessed by measuring animals' abdominal responses to colorectal distension. Repeated treatment with the selective CA IV inhibitors AB-118 and NIK-67 effectively counteracted the development of visceral pain induced by DNBS. In addition to pain relief, AB-118 showed a protective effect against colon damage. By contrast, the anti-hyperalgesic activity of NIK-67 was independent of colon healing, suggesting a direct protective effect of NIK-67 on visceral sensitivity. The enzymatic activity and the expression of CA IV resulted significantly increased after DNBS injection. NIK-67 normalised CA IV activity in DNBS animals, while AB-118 was partially effective. None of these compounds influenced CA IV expression through the colon. Although further investigations are needed to study the underlying mechanisms, CA IV inhibitors are promising candidates in the search for therapies to relieve visceral pain in IBDs.

Uncovering the interplay between pH receptors and immune cells: Potential drug targets (Review)

Extracellular acidosis is associated with various immunopathological states. The microenvironment of numerous solid tumours and inflammatory responses during acute or chronic infection are all related to a pH range of 5.5‑7.0. The relationship between inflammation and immune escape, cancer metabolism, and immunologic suppression drives researchers to focus on the effects of low pH on diverse components of disease immune monitoring. The potential effect of low extracellular pH on the immune function reveals the importance of pH in inflammatory and immunoreactive processes. In this review, the mechanism of how pH receptors, including monocarboxylate transporters (MCTs), Na⁺/H⁺ exchanger 1, carbonic anhydrases (CAs), vacuolar‑ATPase, and proton‑sensing G‑protein coupled receptors (GPCRs), modulate the immune system in disease, especially in cancer, were studied. Their role in immunocyte growth and signal transduction as part of the immune response, as well as cytokine production, have been documented in great detail. Currently, immunotherapy strategies have positive therapeutic effects for patients. However, the acidic microenvironment may block the effect of immunotherapy through compensatory feedback mechanisms, leading to drug resistance. Therefore, we highlight promising therapeutic developments regarding pH manipulation and provide a framework for future research.

Salivary proteome of aphthous stomatitis reveals the participation of vitamin metabolism, nutrients, and bacteria

There are currently no preventative options for recurrent aphthous stomatitis, and the only available treatments are palliative. This is partly due to a poor understanding of its etiopathogenesis. In this case-control study, we characterized the salivary proteome of patients with recurrent aphthous stomatitis in the presence and absence of lesions. Through mass spectrometry-based proteomics and bioinformatics tools, we identified that the presence of oral ulcers is associated with several specific biological processes, including the metabolic pathways of vitamin B9, B12, nitrogen, selenium, and the bacterium Neisseria meningitidis. These changes occurred only in the presence of clinically visible lesions, and there were no relevant differences between patients in anatomical regions unaffected by ulcers. Additionally, using western blot and ELISA assays, we verified that carbonic anhydrase 1 (CA1) and hemoglobin subunit beta (HBB) proteins are highly expressed during the ulcerative and remission phases of recurrent aphthous stomatitis. Our results cumulatively support saliva as an indicator of the pathophysiological changes, which occur during the clinical course of lesions. From a clinical perspective, we suggest that recurrent aphthous stomatitis is a condition triggered by temporary biological changes in people with lesions.

Acute Hemodynamic Effect of Acetazolamide in Patients With Pulmonary Hypertension Whilst Breathing Normoxic and Hypoxic Gas: A Randomized Cross-Over Trial

Aims: To test the acute hemodynamic effect of acetazolamide in patients with pulmonary hypertension (PH) under ambient air and hypoxia.

Methods: Patients with pulmonary arterial or chronic thromboembolic PH (PAH/CTEPH) undergoing right heart catheterization were included in this randomized, placebo-controlled, double-blinded, crossover trial. The main outcome, pulmonary vascular resistance (PVR), further hemodynamics, blood- and cerebral oxygenation were measured 1 h after intravenous administration of 500 mg acetazolamide or placebo-saline on ambient air (normoxia) and at the end of breathing hypoxic gas (F_IO₂ 0.15, hypoxia) for 15 min.

Results: 24 PH-patients, 71% men, mean ± SD age 59 ± 14 years, BMI 28 ± 5 kg/m², PVR 4.7 ± 2.1 WU participated. Mean PVR after acetazolamide vs. placebo was 5.5 ± 3.0 vs. 5.3 ± 3.0 WU; mean difference (95% CI) 0.2 (−0.2–0.6, p = 0.341). Heart rate was higher after acetazolamide (79 ± 12 vs. 77 ± 11 bpm, p = 0.026), pH was lower (7.40 ± 0.02 vs. 7.42 ± 0.03, p = 0.002) but PaCO₂ and PaO₂ remained unchanged while cerebral tissue oxygenation increased (71 ± 6 vs. 69 ± 6%, p = 0.017). In acute hypoxia, acetazolamide decreased PVR by 0.4 WU (0.0–0.9, p = 0.046) while PaO₂ and PaCO₂ were not changed. No adverse effects occurred.

Conclusions: In patients with PAH/CTEPH, i.v. acetazolamide did not change pulmonary hemodynamics compared to placebo after 1 hour in normoxia but it reduced PVR after subsequent acute exposure to hypoxia. Our findings in normoxia do not suggest a direct acute pulmonary vasodilator effect of acetazolamide. The reduction of PVR during hypoxia requires further corroboration. Whether acetazolamide improves PH when given over a prolonged period by stimulating ventilation, increasing oxygenation, and/or altering vascular inflammation and remodeling remains to be investigated.

Carbonic anhydrase inhibitors suppress seizures in a rat model of birth asphyxia

OBJECTIVE

Seizures are common in neonates recovering from birth asphyxia but there is general consensus that current pharmacotherapy is suboptimal and that novel antiseizure drugs are needed. We recently showed in a rat model of birth asphyxia that seizures are triggered by the post-asphyxia recovery of brain pH. Here our aim was to investigate whether carbonic anhydrase inhibitors (CAIs), which induce systemic acidosis, block the post-asphyxia seizures.

METHODS

The CAIs acetazolamide (AZA), benzolamide (BZA), and ethoxzolamide (EZA) were administered intraperitoneally or intravenously to 11-day-old rats exposed to intermittent asphyxia (30 min; three 7+3 min cycles of 9% and 5% O₂ at 20% CO₂ ). Electrode measurements of intracortical pH, Po₂ , and local field potentials (LFPs) were made under urethane anesthesia. Convulsive seizures and blood acid-base parameters were examined in freely behaving animals.

RESULTS

The three CAIs decreased brain pH by 0.14-0.17 pH units and suppressed electrographic post-asphyxia seizures. AZA, BZA, and EZA differ greatly in their lipid solubility (EZA > AZA > BZA) and pharmacokinetics. However, there were only minor differences in the delay (range 0.8-3.7 min) from intraperitoneal application to their action on brain pH. The CAIs induced a modest post-asphyxia elevation of brain Po₂ that had no effect on LFP activity. AZA was tested in freely behaving rats, in which it induced a respiratory acidosis and decreased the incidence of convulsive seizures from 9 of 20 to 2 of 17 animals.

SIGNIFICANCE

AZA, BZA, and EZA effectively block post-asphyxia seizures. Despite the differences in their pharmacokinetics, they had similar effects on brain pH, which indicates that their antiseizure mode of action was based on respiratory (hypercapnic) acidosis resulting from inhibition of blood-borne and extracellular vascular carbonic anhydrases. AZA has been used for several indications in neonates, suggesting that it can be safely repurposed for the treatment of neonatal seizures as an add-on to the current treatment regimen.

Piperazine and piperidine-substituted 7-hydroxy coumarins for the development of anti-inflammatory agents

Coumarins (2H-1-benzopyran-2-one), derivatives that can be isolated from several plants, have been reported for their anticoagulant, antimicrobial, anti-inflammatory, or anticancer activity. Some of these structures are currently approved for the treatment of cardiovascular diseases, as antibiotics or as an anticancer drug. Given the great potential of this structure and the limited number of studies that focus on molecules derived from carbon 8 of the benzopyranone heterocycle, we synthesized in this project 38 coumarin derivatives by substituting carbon 8 of the benzopyran ring with some aromatic and aliphatically substituted piperidines and piperazines. As a few of these structures were already shown to exhibit some carbonic anhydrase (CA) inhibition and as CA enzymes are reported to be closely related to inflammation, the synthesized derivatives were evaluated for their anti-inflammatory activity in vitro. The results indicated that compounds 20 and 31 revealed promising anti-inflammatory activity, as they demonstrated better activity than the reference drugs.

Drug Repurposing to Treat Glucocorticoid Resistance in Asthma

Corticosteroid resistance causes significant morbidity in asthma, and drug repurposing may identify timely and cost-effective adjunctive treatments for corticosteroid resistance. In 95 subjects from the Childhood Asthma Management Program (CAMP) and 19 subjects from the Severe Asthma Research Program (SARP), corticosteroid response was measured by the change in percent predicted forced expiratory volume in one second (FEV₁). In each cohort, differential gene expression analysis was performed comparing poor (resistant) responders, defined as those with zero to negative change in FEV₁, to good responders, followed by Connectivity Map (CMap) analysis to identify inversely associated (i.e., negatively connected) drugs that reversed the gene expression profile of poor responders to resemble that of good responders. Mean connectivity scores weighted by sample size were calculated. The top five drug compound candidates underwent in vitro validation in NF-κB-based luciferase reporter A549 cells stimulated by IL-1β ± dexamethasone. In CAMP and SARP, 134 and 178 respective genes were differentially expressed in poor responders. CMap analysis identified 46 compounds in common across both cohorts with connectivity scores < −50. γ-linolenic acid, ampicillin, exemestane, brinzolamide, and INCA-6 were selected for functional validation. γ-linolenic acid, brinzolamide, and INCA-6 significantly reduced IL-1β induced luciferase activity and potentiated the anti-inflammatory effect of dexamethasone in A549/NF-κB-luc reporter cells. These results demonstrate how existing drugs, including γ-linolenic acid, brinzolamide, and INCA-6, may be repurposed to improve corticosteroid response in asthmatics.

Trichinella spiralis-induced mastocytosis and erythropoiesis are simultaneously supported by a bipotent mast cell/erythrocyte precursor cell

Anti-helminth responses require robust type 2 cytokine production that simultaneously promotes worm expulsion and initiates the resolution of helminth-induced wounds and hemorrhaging. However, how infection-induced changes in hematopoiesis contribute to these seemingly distinct processes remains unknown. Recent studies have suggested the existence of a hematopoietic progenitor with dual mast cell-erythrocyte potential. Nonetheless, whether and how these progenitors contribute to host protection during an active infection remains to be defined. Here, we employed single cell RNA-sequencing and identified that the metabolic enzyme, carbonic anhydrase (Car) 1 marks a predefined bone marrow-resident hematopoietic progenitor cell (HPC) population. Next, we generated a Car1-reporter mouse model and found that Car1-GFP positive progenitors represent bipotent mast cell/erythrocyte precursors. Finally, we show that Car1-expressing HPCs simultaneously support mast cell and erythrocyte responses during Trichinella spiralis infection. Collectively, these data suggest that mast cell/erythrocyte precursors are mobilized to promote type 2 cytokine responses and alleviate helminth-induced blood loss, developmentally linking these processes. Collectively, these studies reveal unappreciated hematopoietic events initiated by the host to combat helminth parasites and provide insight into the evolutionary pressure that may have shaped the developmental relationship between mast cells and erythrocytes.

Helminth parasites infect approximately 2 billion people and represent a significant public health concern. Helminths undertake complex developmental life cycles through multiple organs and as a result cause substantial tissue damage. To combat this, mammals have evolved mechanisms to initiate balanced immune responses that promote inflammation needed to seclude parasites in granulomas, reduce parasitic burdens and mitigate the consequences of helminth-induced wounds. Despite their clinical importance, the mechanisms that regulate these events remain poorly defined. Here we have uncovered a unique progenitor cell that supports both proinflammatory mast cell responses and red blood cell development, thereby simultaneously initiating both of these host-protective responses. Collectively, these studies reveal unappreciated events initiated by the host to combat pathogens that infect billions of individuals worldwide.

Carbonic Anhydrase Inhibition Ameliorates Inflammation and Experimental Pulmonary Hypertension

Inflammation and vascular smooth muscle cell (VSMC) phenotypic switching are causally linked to pulmonary arterial hypertension (PAH) pathogenesis. Carbonic anhydrase inhibition induces mild metabolic acidosis and exerts protective effects in hypoxic pulmonary hypertension. Carbonic anhydrases and metabolic acidosis are further known to modulate immune cell activation. To evaluate if carbonic anhydrase inhibition modulates macrophage activation, inflammation, and VSMC phenotypic switching in severe experimental pulmonary hypertension, pulmonary hypertension was assessed in Sugen 5416/hypoxia (SU/Hx) rats after treatment with acetazolamide or ammonium chloride (NH4Cl). We evaluated pulmonary and systemic inflammation and characterized the effect of carbonic anhydrase inhibition and metabolic acidosis in alveolar macrophages and bone marrow-derived macrophages (BMDMs). We further evaluated the treatment effects on VSMC phenotypic switching in pulmonary arteries and pulmonary artery smooth muscle cells (PASMCs) and corroborated some of our findings in lungs and pulmonary arteries of patients with PAH. Both patients with idiopathic PAH and SU/Hx rats had increased expression of lung inflammatory markers and signs of PASMC dedifferentiation in pulmonary arteries. Acetazolamide and NH4Cl ameliorated SU/Hx-induced pulmonary hypertension and blunted pulmonary and systemic inflammation. Expression of carbonic anhydrase isoform 2 was increased in alveolar macrophages from SU/Hx animals, classically (M1) and alternatively (M2) activated BMDMs, and lungs of patients with PAH. Carbonic anhydrase inhibition and acidosis had distinct effects on M1 and M2 markers in BMDMs. Inflammatory cytokines drove PASMC dedifferentiation, and this was inhibited by acetazolamide and acidosis. The protective antiinflammatory effect of acetazolamide in pulmonary hypertension is mediated by a dual mechanism of macrophage carbonic anhydrase inhibition and systemic metabolic acidosis.

Proteomic Investigation of a Diseased Gorgonian Coral Indicates Disruption of Essential Cell Function and Investment in Inflammatory and Other Immune Processes

As scleractinian coral cover declines in the face of increased frequency in disease outbreaks, future reefs may become dominated by octocorals. Understanding octocoral disease responses and consequences is therefore necessary if we are to gain insight into the future of ecosystem services provided by coral reefs. In Florida, populations of the octocoral Eunicea calyculata infected with Eunicea black disease (EBD) were observed in the field in the fall of 2011. This disease was recognized by a stark, black pigmentation caused by heavy melanization. Histological preparations of E. calyculata infected with EBD demonstrated granular amoebocyte (GA) mobilization, melanin granules in much of the GA population, and the presence of fungal hyphae penetrating coral tissue. Previous transcriptomic analysis also identified immune trade-offs evidenced by increased immune investment at the expense of growth. Our investigation utilized proteogenomic techniques to reveal decreased investment in general cell signaling while increasing energy production for immune responses. Inflammation was also prominent in diseased E. calyculata and sheds light on factors driving the extreme phenotype observed with EBD. With disease outbreaks continuing to increase in frequency, our results highlight new targets within the cnidarian immune system and provide a framework for understanding transcriptomics in the context of an organismal disease phenotype and its protein expression.

First Responders: Innate Immunity to Helminths

Helminth infections represent a significant public health concern resulting in devastating morbidity and economic consequences across the globe. Helminths migrate through mucosal sites causing tissue damage and the induction of type 2 immune responses. Antihelminth protection relies on the mobilization and activation of multiple immune cells, including type 2 innate lymphocytes (ILC2s), basophils, mast cells, macrophages, and hematopoietic stem/progenitor cells. Further, epithelial cells and neurons have been recognized as important regulators of type 2 immunity. Collectively, these pathways stimulate host-protective responses necessary for worm expulsion and the healing of affected tissues. In this review we focus on the innate immune pathways that regulate immunity to helminth parasites and describe how better understanding of these pathways may lead to the development of new therapeutic strategies.

Carbonic anhydrase enzymes for regulating mast cell hematopoiesis and type-2 inflammation: a patent evaluation (WO2017/058370)

INTRODUCTION

Activity modulators of carbonic anhydrases hold great potential for several therapeutic applications against ophthalmologic and neurological disease, cancer, and infectious diseases. The involvement of carbonic anhydrase in the regulation of mast cell response opens new ways for the treatment of mastocytosis, allergic inflammation, and parasite infection. Areas covered: The application claims the use of carbonic anhydrase activity modulators (inhibitors or activators) for treating allergic disease, bacterial infection, fungal infection, viral infection, mastocytosis, or mast cell-mediated inflammation. Expert opinion: Although there is a lack of essential biological data, this patent proposes a new type of applications for carbonic anhydrase inhibitors and deserves further studies. This may lead to new advances in the field of carbonic anhydrase with potential therapeutic implications in the management of type-2 inflammation.

Immune Cell Responses and Cytokine Profile in Intestines of Mice Infected with Trichinella spiralis

The intestinal phase is critical for trichinellosis caused by Trichinella spiralis (T. spiralis), as it determines both process and consequences of the disease. Several previous studies have reported that T. spiralis induces the initial predominance of a Th1 response during the intestine stage and a subsequent predominance of a Th2 response during the muscle stage. In the present study, immune cells and cytokine profile were investigated in the intestine of mice infected with T. spiralis. The results showed that the number of eosinophils, goblet cells, mucosal mast cells, and 33D1+ dendritic cells (DCs) increased during the intestinal phase of the infection. Among these, eosinophils, goblet cells, and mucosal mast cells continued to increase until 17 days post infection (dpi), and the number of 33D1+ DCs increased compared to wild type; however, it did not change with the days of infection. The mRNA and protein levels of Th1 cytokines IL-2, IL-12, and IFN-γ and the Th2 cytokines IL-4, IL-5, IL-10, IL-13, and TGF-β were all increased in the tissues of the small intestine in infected mice; however, in general, Th2 cytokines increased more than Th1 cytokines. In conclusion, our findings suggest that T. spiralis infection can induce an increase of small intestine mucosal immune cells and add further evidence to show that the intestinal mucosal immune system of infected mice was induced toward mixed Th1/Th2 phenotypes with the predominance of Th2 response at the early stage of infection.

Type 2 cytokine responses: regulating immunity to helminth parasites and allergic inflammation

Purpose of Review

It is well established that T helper type 2 (T_H2) immune responses are necessary to provide protection against helminth parasites but also to promote the detrimental inflammation associated with allergies and asthma. Given the importance of type 2 immunity and inflammation, many studies have focused on better understanding the factors that regulate T_H2 cell development and activation. As a result, significant progress has been made in understanding the signaling pathways and molecular events necessary to promote T_H2 cell polarization. In addition to the adaptive compartment, emerging studies are better defining the innate immune pathways needed to promote T_H2 cell responses. Given the recent and substantial growth of this field, the purpose of this review is to highlight recent studies defining the innate immune events that promote immunity to helminth parasites and allergic inflammation.

Recent Findings

Emerging studies have begun to elucidate the importance of cytokine alarmins such as thymic stromal lymphopoietin (TSLP), IL-25 (IL-17E) and IL-33 in promoting type 2 immunity and inflammation following helminth challenge or exposure to allergens. Specifically, recent reports have begun to define the complex cellular networks these alarmins activate and their contribution to type 2 immunity and inflammation.

Summary

Our increased understanding of the pathways that regulate type 2 cytokine-mediated immunity and inflammation have revealed novel therapeutic targets to treat both helminth infections and allergic disease states.

The role of rare innate immune cells in Type 2 immune activation against parasitic helminths

The complexity of helminth macroparasites is reflected in the intricate network of host cell types that participate in the Type 2 immune response needed to battle these organisms. In this context, adaptive T helper 2 cells and the Type 2 cytokines interleukin (IL)-4, IL-5, IL-9 and IL-13 have been the focus of research for years, but recent work has demonstrated that the innate immune system plays an essential role. Some innate immune cells that promote Type 2 immunity are relatively abundant, such as macrophages and eosinophils. However, we now appreciate that more rare cell types including group 2 innate lymphoid cells, basophils, mast cells and dendritic cells make significant contributions to these responses. These cells are found at low frequency but they are specialized to their roles - located at sites such as the skin, lung and gut, where the host combats helminth parasites. These cells respond rapidly and robustly to worm antigens and worm-induced damage to produce essential cytokines, chemokines, eicosanoids and histamine to activate damaged epithelium and to recruit other effectors. Thus, a greater understanding of how these cells operate is essential to understand how the host protects itself during helminth infection.

SWATH-based proteomics identified carbonic anhydrase 2 as a potential diagnosis biomarker for nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a serious threat to public health, and the biomarker discovery is of urgent needs. The data-independent mode (DIA) based sequential window acquisition of all theoretical fragment-ion spectra (SWATH) mass spectrometry (MS) has been proved to be precise in protein quantitation and efficient for cancer biomarker researches. In this study, we performed the first SWATH-MS analysis comparing the NPC and normal tissues. Spike-in stable isotope labeling by amino acids in cell culture (super-SILAC) MS was used as a shotgun reference. We identified and quantified 1414 proteins across all SWATH-MS analyses. We found that SWATH-MS had a unique feature to preferentially detect proteins with smaller molecular weights than either super-SILAC MS or human proteome background. With SWATH-MS, 29 significant differentially express proteins (DEPs) were identified. Among them, carbonic anhydrase 2 (CA2) was selected for further validation per novelty, MS quality and other supporting rationale. With the tissue microarray analysis, we found that CA2 had an AUC of 0.94 in differentiating NPC from normal tissue samples. In conclusion, SWATH-MS has unique features in proteome analysis, and it leads to the identification of CA2 as a potentially new diagnostic biomarker for NPC.