T-helper Cell Type Research Articles

Metabolic and ionic control of T cells in asthma endotypes.

CD4+ T cells play a central role in orchestrating the immune response in asthma, with dysregulated ion channel profiles and altered metabolic signatures contributing to disease progression and severity. An important classification of asthma is based on the presence of T-helper cell type 2 (Th2) inflammation, dividing patients into Th2-high and Th2-low endotypes. These distinct endotypes have implications for disease severity, treatment response, and prognosis. By elucidating how ion channels and energy metabolism control Th cells in asthma, this review contributes to the pathophysiological understanding and the prospective development of personalized therapeutic treatment strategies for patients suffering from distinct asthma endotypes.

Structural Insights and Catalytic Mechanism of 3-Hydroxybutyryl-CoA Dehydrogenase from Faecalibacterium Prausnitzii A2-165.

Atopic dermatitis (AD) is characterized by a T-helper cell type 2 (Th2) inflammatory response leading to skin damage with erythema and edema. Comparative fecal sample analysis has uncovered a strong correlation between AD and Faecalibacterium prausnitzii strain A2-165, specifically associated with butyrate production. Therefore, understanding the functional mechanisms of crucial enzymes in the butyrate pathway, such as 3-hydroxybutyryl-CoA dehydrogenase of A2-165 (A2HBD), is imperative. Here, we have successfully elucidated the three-dimensional structure of A2HBD in complex with acetoacetyl-CoA and NAD+ at a resolution of 2.2Å using the PAL-11C beamline (third generation). Additionally, X-ray data of A2HBD in complex with acetoacetyl-CoA at a resolution of 1.9 Å were collected at PAL-XFEL (fourth generation) utilizing Serial Femtosecond Crystallography (SFX). The monomeric structure of A2HBD consists of two domains, N-terminal and C-terminal, with cofactor binding occurring at the N-terminal domain, while the C-terminal domain facilitates dimerization. Our findings elucidate the binding mode of NAD+ to A2HBD. Upon acetoacetyl-CoA binding, the crystal structure revealed a significant conformational change in the Clamp-roof domain (root-mean-square deviation of 2.202 Å). Notably, residue R143 plays a critical role in capturing the adenine phosphate ring, underlining its significance in substrate recognition and catalytic activity. The binding mode of acetoacetyl-CoA was also clarified, indicating its lower stability compared to NAD+. Furthermore, the conformational change of hydrophobic residues near the catalytic cavity upon substrate binding resulted in cavity shrinkage from an open to closed conformation. This study confirms the conformational changes of catalytic triads involved in the catalytic reaction and presents a proposed mechanism for substrate reduction based on structural observations.

Clinical importance of cerebrospinal fluid protein levels in HIV-associated cryptococcal meningitis: Insights from a prospective cohort study in Uganda.

Cerebrospinal fluid (CSF) protein levels exhibit high variability in HIV-associated cryptococcal meningitis; however, its clinical implications remain unclear. We analyzed data from 890 adults with HIV-associated cryptococcal meningitis randomized into two clinical trials in Uganda between 2015 and 2021. CSF protein was grouped into < 100mg/dl (72%, n =641) and ≥ 100mg/dl (28%, n =249). We described baseline clinical variables and 18-week mortality by CSF protein groups. Those with CSF protein ≥ 100mg/dl were more likely to present with Glasgow coma scale score<15 (P < .01), self-reported seizures at baseline (P = .02), higher CD4 T-cell count (P < .001), and higher CSF white blood cells (P < .001). Moreover, those with a baseline CSF protein ≥ 100mg/dl also had a lower baseline CSF fungal burden (P < .001) and a higher percentage of sterile CSF cultures at day 14 (P = .02). Individuals with CSF protein ≥ 100mg/dl demonstrated a more pronounced immune response consisting of upregulation of immune effector molecules, pro-inflammatory cytokines, T-helper cell type 1 and 17 cytokines, and immune-exhaustion marker (P < .05). 18-week mortality risk in individuals with a CSF protein < 100mg/dl was 34% higher (unadjusted Hazard Ratio 1.34; 95% Confidence Interval, 1.05-1.70; P = .02) than those with CSF protein ≥ 100mg/dl. In HIV-associated cryptococcal meningitis, individuals with baseline CSF protein ≥ 100mg/dl more frequently presented with neurological symptoms, higher CSF inflammatory cytokines, reduced fungal burden, and lower mortality risk. The findings underscore the prognostic significance of baseline CSF protein levels in predicting disease severity and mortality risk in cryptococcal meningitis.

565 – Safety and pharmacokinetic profiles of a humanized monoclonal antibody TQH2722 targeting interleukin 4 receptor alpha (IL-4Rα) in health adult subjects

Abstract Introduction/Background TQH2722 is a humanized monoclonal antibody targeting interleukin 4 receptor alpha (IL4Rα) which leads to the dual-blockade of interleukin-4 (IL-4) and interleukin-13 (IL-13) signaling, inhibiting the T-helper cell type 2 immune pathway. Th2 inflammation is implicated in the pathobiology of diseases such as asthma and atopic dermatitis. We describe the safety and pharmacokinetic results from a first-in-human study in healthy subjects. Objectives To evaluate the safety, tolerability, pharmacokinetic characteristics, and immunogenicity of TQH2722 injection in healthy adult subjects. Methods This randomized, double-blind, placebo-controlled, ascending-dose phase I study (NCT05409326) was conducted in China. Each adult subject received a single subcutaneous (sc.) TQH2722 dose or placebo in single ascending-dose (SAD) cohorts, and 4 doses of TQH2722 or placebo administrated Q2W in multiple ascending-dose (MAD) cohorts. Pharmacokinetic samples were collected prior to first dose administration through 56 days after initial dosing in SAD cohorts. In the MAD cohorts, samples were collected before every administration until 56 days after last dosing. Results As of 28 September 2023, all subjects had completed the study, with the database locked while remaining unblinded. Sixty-six (66) healthy subjects were enrolled in this study. The SAD cohorts consisted of single doses of TQH2722 of 50 mg (n-4), 150 mg (n=10 active, 2 placebo), 300, 600, and 1200 mg cohorts, each receiving TQH2722 (n=8) or placebo (n=2). Ten subjects were enrolled in each of the 150 and 600 mg MAD cohorts receiving TQH2722 (n=8) or placebo (n=2). No dose-limiting toxicities or SAEs were observed and only 3 subjects experienced a grade 3 AE including 1 subject of increased triglycerides, 1 subject with increased creatine kinase and 1 subject with decreased blood potassium). All other AEs were of grade 1 or 2. The incidence and severity of AEs were not dose dependent. No SAEs or AEs led to treatment discontinuation. The pharmacokinetics of TQH2722 were indicative of an anti-receptor mAb in that TQH2722 exhibited nonlinear target-mediated clearance. Maximum serum concentration was reached after 2.78-6.75 days with the half-life of a single sc. administration of TQH2722 increasing by dose level, ranging between 4 and 18 days. Conclusions TQH2722 was safe and well tolerated in healthy volunteers. Injection site reactions and laboratory abnormalities were the most reported AEs, with grade 1-2 as the major severity. Most AEs resolved on their own. Single dosing showed non-linear increases of the drug exposure as the dosage increased. These data support further clinical development of TQH2722 as a therapeutic treatment for patients with Atopic Dermatitis and other related diseases mediated by Th2 inflammation.

Comparative study of acetalated-dextran microparticle fabrication methods for a clinically translatable subunit-based influenza vaccine

The most common influenza vaccines are inactivated viruses produced in chicken eggs, which is a time-consuming production method with variable efficacy due to mismatches of the vaccine strains to the dominant circulating strains. Subunit-based vaccines provide faster production times in comparison to the traditional egg-produced vaccines but often require the use of an adjuvant to elicit a highly protective immune response. However, the current FDA approved adjuvant for influenza vaccines (MF59) elicits a primarily helper T-cell type 2 (Th2)-biased humoral immune response. Adjuvants that can stimulate a Th1 cellular response are correlated to have more robust protection against influenza. The cyclic dinucleotide cGAMP has been shown to provide a potent Th1 response but requires the use of a delivery vehicle to best initiate its signalling pathway in the cytosol. Herein, acetalated dextran (Ace-DEX) was used as the polymer to fabricate microparticles (MPs) via double-emulsion, electrospray, and spray drying methods to encapsulate cGAMP. This study compared each fabrication method’s ability to encapsulate and retain the hydrophilic adjuvant cGAMP. We compared their therapeutic efficacy to Addavax, an MF59-like adjuvant, and cGAMP Ace-DEX MPs provided a stronger Th1 response in vaccinated BALB/c mice. Furthermore, we compared Ace-DEX MPs to spray dried MPs composed from a commonly used polymer for drug delivery, poly(lactic-co-glycolic acid) (PLGA). We observed that all Ace-DEX MPs elicited similar humoral and cellular responses to the PLGA MPs. Overall, the results shown here indicate Ace-DEX can perform similarly to PLGA as a polymer for drug delivery and that spray drying can provide an efficient way to produce MPs to encapsulate cGAMP and stimulate the immune system.

Deep Immunophenotyping Unveils Depletion of Anti-inflammatory T-helper Type-2 Cells (Th2) and Links Loss of Alternatively-Activated-Monocytes (M2) to Vasospasm and Delayed Cerebral Ischemia Following Subarachnoid Hemorrhage

Deep Immunophenotyping Unveils Depletion of Anti-inflammatory T-helper Type-2 Cells (Th2) and Links Loss of Alternatively-Activated-Monocytes (M2) to Vasospasm and Delayed Cerebral Ischemia Following Subarachnoid Hemorrhage

Mycobacterium tuberculosis Rv1987 protein attenuates inflammatory response and consequently alters microbiota in mouse lung.

Healthy lung microbiota plays an important role in preventing Mycobacterium tuberculosis (Mtb) infections by activating immune cells and stimulating production of T-helper cell type 1 cytokines. The dynamic stability of lung microbiota relies mostly on lung homeostasis. In our previous studies, we found that Mtb virulence factor, Rv1987 protein, can mediate host immune response and enhance mycobacterial survival in host lung. However, the alteration of lung microbiota and the contribution of lung microbiota dysbiosis to mycobacterial evasion in this process are not clear so far. M. smegmatis which does not contain the ortholog of Rv1987 protein was selected as a model strain to study the effects of Rv1987 on host lung microbiota. The lung microbiota, immune state and metabolites of mice infected by M. smegmatis overexpressing Rv1987 protein (MS1987) were detected and analyzed. The results showed that Rv1987 inhibited inflammatory response in mouse lung and anaerobic bacteria and Proteobacteria, Bacteroidota, Actinobacteriota and Acidobacteriota bacteria were enriched in the lung tissues correspondingly. The immune alterations and microbiota dysbiosis affected host metabolic profiles, and some of significantly altered bacteria in MS1987-infected mouse lung, such as Delftia acidovorans, Ralstonia pickettii and Escherichia coli, led to anti-inflammatory responses in mouse lung. The secretory metabolites of these altered bacteria also influenced mycobacterial growth and biofilm formation directly. All these results suggested that Rv1987 can attenuate inflammatory response and alter microbiota in the lung, which in turn facilitates mycobacterial survival in the host.

Sensing of protease activity as a triggering mechanism of Th2 cell immunity and allergic disease.

CD4 T-helper cell type 2 (Th2) cells mediate host defense against extracellular parasites, like helminths. However, Th2 cells also play a pivotal role in the onset and progression of allergic inflammatory diseases such as atopic dermatitis, allergic rhinitis, asthma, and food allergy. This happens when allergens, which are otherwise harmless foreign proteins, are mistakenly identified as "pathogenic." Consequently, the encounter with these allergens triggers the activation of specific Th2 cell responses, leading to the development of allergic reactions. Understanding the molecular basis of allergen sensing is vital for comprehending how Th2 cell responses are erroneously initiated in individuals with allergies. The presence of protease activity in allergens, such as house dust mites (HDM), pollen, fungi, or cockroaches, has been found to play a significant role in triggering robust Th2 cell responses. In this review, we aim to examine the significance of protease activity sensing in foreign proteins for the initiation of Th2 cell responses, highlighting how evolving a host protease sensor may contribute to detect invading helminth parasites, but conversely can also trigger unwanted reactions to protease allergens. In this context, we will explore the recognition receptors activated by proteolytic enzymes present in major allergens and their contribution to Th2-mediated allergic responses. Furthermore, we will discuss the coordinated efforts of sensory neurons and epithelial cells in detecting protease allergens, the subsequent activation of intermediary cells, including mast cells and type 2 innate lymphoid cells (ILC2s), and the ultimate integration of all signals by conventional dendritic cells (cDCs), leading to the induction of Th2 cell responses. On the other hand, the review highlights the role of monocytes in the context of protease allergen exposure and their interaction with cDCs to mitigate undesirable Th2 cell reactions. This review aims to provide insights into the innate functions and cell communications triggered by protease allergens, which can contribute to the initiation of detrimental Th2 cell responses, but also promote mechanisms to effectively suppress their development.

Cell-type-specific role of P2Y2 receptor in HDM-driven model of allergic airway inflammation.

Allergic airway inflammation (AAI) is a chronic respiratory disease that is considered a severe restriction in daily life and is accompanied by a constant risk of acute aggravation. It is characterized by IgE-dependent activation of mast cells, infiltration of eosinophils, and activated T-helper cell type 2 (Th2) lymphocytes into airway mucosa. Purinergic receptor signaling is known to play a crucial role in inducing and maintaining allergic airway inflammation. Previous studies in an ovalbumin (OVA)-alum mouse model demonstrated a contribution of the P2Y2 purinergic receptor subtype (P2RY2) in allergic airway inflammation. However, conflicting data concerning the mechanism by which P2RY2 triggers AAI has been reported. Thus, we aimed at elucidating the cell-type-specific role of P2RY2 signaling in house dust mite (HDM)-driven model of allergic airway inflammation. Thereupon, HDM-driven AAI was induced in conditional knockout mice, deficient or intact for P2ry2 in either alveolar epithelial cells, hematopoietic cells, myeloid cells, helper T cells, or dendritic cells. To analyze the functional role of P2RY2 in these mice models, flow cytometry of bronchoalveolar lavage fluid (BALF), cytokine measurement of BALF, invasive lung function measurement, HDM re-stimulation of mediastinal lymph node (MLN) cells, and lung histology were performed. Mice that were subjected to an HDM-based model of allergic airway inflammation resulted in reduced signs of acute airway inflammation including eosinophilia in BALF, peribronchial inflammation, Th2 cytokine production, and bronchial hyperresponsiveness in mice deficient for P2ry2 in alveolar epithelial cells, hematopoietic cells, myeloid cells, or dendritic cells. Furthermore, the migration of bone-marrow-derived dendritic cells and bone-marrow-derived monocytes, both deficient in P2ry2, towards ATP was impaired. Additionally, we found reduced levels of MCP-1/CCL2 and IL-8 homologues in the BALF of mice deficient in P2ry2 in myeloid cells and lower concentrations of IL-33 in the lung tissue of mice deficient in P2ry2 in alveolar epithelial cells. In summary, our results show that P2RY2 contributes to HDM-induced airway inflammation by mediating proinflammatory cytokine production in airway epithelial cells, monocytes, and dendritic cells and drives the recruitment of lung dendritic cells and monocytes.

Insight on the hub gene associated signatures and potential therapeutic agents in epilepsy and glioma

ObjectiveThe relationship between epilepsy and glioma has long been widely recognized, but the mechanisms of interaction remain unclear. This study aimed to investigate the shared genetic signature and treatment strategies between epilepsy and glioma. MethodsWe subjected hippocampal tissue samples from patients with epilepsy and glioma to transcriptomic analysis to identify differential genes and associated pathways, respectively. Weight gene co-expression network (WGCNA) analysis was performed to identify conserved modules in epilepsy and glioma and to obtain differentially expressed conserved genes. Prognostic and diagnostic models were built using lasso regression. We also focused on building transcription factor-gene interaction networks and assessing the proportion of immune invading cells in epilepsy patients. Finally, drug compounds were inferred using a drug signature database (DSigDB) based on core targets. ResultsWe discovered 88 differently conserved genes, most of which are involved in synaptic signaling and calcium ion pathways. We used lasso regression model to reduce 88 characteristic genes, and finally screened out 14 genes (EIF4A2, CEP170B, SNPH, EPHA4, KLK7, GNG3, MYOP, ANKRD29, RASD2, PRRT3, EFR3A, SGIP1, RAB6B, CNNM1) as the features of glioma prognosis model whose ROC curve is 0.9. Then, we developed a diagnosis model for epilepsy patients using 8 genes (PRRT3, RASD2, MYPOP, CNNM1, ANKRD29, GNG3, SGIP1, KLK7) with area under ROC curve (AUC) values near 1. According to the ssGSEA method, we observed an increase in activated B cells, eosinophils, follicular helper T cells and type 2T helper cells, and a decrease in monocytes in patients with epilepsy. Notably, the great majority of these immune cells showed a negative correlation with hub genes. To reveal the transcriptional-level regulation mechanism, we also built a TF-gene network. In addition, we discovered that patients with glioma-related epilepsy may benefit more from gabapentin and pregabalin. ConclusionThis study reveals the modular conserved phenotypes of epilepsy and glioma and constructs effective diagnostic and prognostic markers. It provides new biological targets and ideas for the early diagnosis and effective treatment of epilepsy.

Cutaneous leishmaniasis: Review Article

Leishmaniasis is a protozoal infection caused by a number of different species in the Leishmania genus. Sandflies are the vectors for the transmission of these protozoa to humans. When macrophages are triggered into a leishmanicidal state, a clinical recovery occurs. In particular, the T-helper cell type 1 (Th1) response is responsible for this, and it is also responsible for preventing the recurrence of latent chronic infection. Regardless of the disease's clinical manifestation, antimonial drugs are the treatment of choice. Amphotericin B is the second-best treatment option. This study focuses on the pathology and treatment of cutaneous leishmaniasis.

IgG4-related ophthalmic disease masquerading as ciliary body tumors and scleritis in both eyes: a case report

BackgroundTo report a rare case of IgG4-related ophthalmic disease (IgG4-ROD) manifesting as intraocular masses and scleritis in both eyes in a 61-year-old male and to investigate the changes in multimodal imaging features of the lesion sites and helper T-cell type 1 (Th 1)/Th 2/Th 17 cytokine levels in the aqueous humor.Case presentationA patient with IgG4-ROD seemingly manifested with an intraocular tumor in the left eye and sequentially, with an inflammatory mass in the ciliary body and scleritis in the right eye. The patient complained of vision loss of 6 months duration in the left eye at his first visit. With a preliminary diagnosis of an intraocular tumor, enucleation of the left eyeball and histopathological examination were performed. Approximately 3 months later, the patient started to experience headache, eye pain, and declining vision in the right eye. Ophthalmic imaging revealed a ciliary mass and scleritis. Th 1/Th 2/Th 17 cytokine levels and multimodal imaging findings were analyzed before and after corticosteroid treatment. Histopathological examination and immunohistochemistry (IHC) of the enucleated left eye demonstrated lymphoplasmacytic infiltration with an IgG4+/IgG+ cell ratio of approximately 40%, pointing to the diagnosis of probable IgG4-ROD. Long-term treatment with corticosteroids led to significant improvement in the signs and symptoms of the left eye. Th 1/Th 2/Th 17 cytokine profile monitoring of the aqueous humor and multimodal imaging of the right eye showed gradual regression of the mass and attenuation of ocular inflammation during treatment.ConclusionsPatients with an atypical presentation of IgG4-ROD, such as intraocular masses and scleritis, are likely to experience a significant delay in diagnosis. This case demonstrates the significance of IgG4-ROD in the differential diagnosis of intraocular tumors and ocular inflammation. IgG4-RD is a newly diagnosed disease with multi-organ involvement and little is known about its pathogenesis, particularly in the eye. The present case will open new challenges in the clinico-pathological diagnosis and research of this disease. Combined investigations of multimodal imaging and cytokine level detection of intraocular fluid provide a new and effective way to monitor disease progression.

Crosstalk between ILC2s and Th2 cells varies among mouse models.

Type 2T helper (Th2) cells and group 2 innate lymphoid cells (ILC2s) provide protection against helminth infection and are involved in allergic responses. However, their relative importance and crosstalk during type 2 immune responses are still controversial. By generating and utilizing mouse strains that are deficient in either ILC2s or Th2 cells, we report that interleukin (IL)-33-mediated ILC2 activation promotes the Th2 cell response to papain; however, the Th2 cell response to ovalbumin (OVA)/alum immunization is thymic stromal lymphopoietin (TSLP) dependent but independent of ILC2s. During helminth infection, ILC2s and Th2 cells collaborate at different phases of the immune responses. Th2 cells, mainly through IL-4 production, induce the expression of IL-25, IL-33, and TSLP, among which IL-25 and IL-33 redundantly promote ILC2 expansion. Thus, while Th2 cell differentiation can occur independently of ILC2s, activation of ILC2s may promote Th2 responses, and Th2 cells can expand ILC2s by inducing type 2 alarmins.

Features of the development of an adaptive antiviral immune response

Both well-known basic cellular and humoral factors of the adaptive antiviral immune response, which play an important role in the effectiveness of immunological reactions to inhibit viral infections, and new factors with which the efficiency of the functioning of cellular and humoral mechanisms of a specific immune response is associated are considered. This is, first of all, the presence of naive T-lymphocytes in the macroorganism, programmed to recognize a specific viral antigen. In addition, this is facilitated by various receptor specificities of T-lymphocytes, of which there are more than 20 million. The diversity of receptor structures was believed to be associated with the functioning of genes that activate recombinase. The development of antiviral cell-mediated mechanisms depends on interleukins 12, interferon-, and the transcriptional activator T-bet. An imbalance in the ratio of T-helper cell types 1 and 2 can lead to memory cell damage. Th-17 plays a central role in controlling the immune response to viral infection. The balance between activated cytotoxic CD-8+/T-helper cells and T-regulatory lymphocytes determines the risk of immunopathology. An excess of effector cells leads to immune-mediated damage, a lack of chronicity of a viral infection. One of the controlling mechanisms that ensure minimal damage to cells and tissues is the assembly of a cytoplasmic protein complex in antigen-presenting cellsinflammasomes. The intensity of inflammatory processes depends on whether the virus is cytopathic. The effectiveness of the humoral immune response is also attributed to the fact that one plasma cell can secrete more than 2,000 antibody molecules per second. One of the powerful properties of the adaptive antiviral immune response is the development of immunological memory by different types of memory T cells. To date, at least three subpopulations of memory T cells with different activation requirements have been identified. Thus, determining how each of these types of memory T-lymphocytes contributes to the long-term antiviral protection of the macroorganism is an urgent task.

Continuous Measurement of Reactive Oxygen Species Formation in Bacteria-infected Bone Marrow-derived Macrophages Using a Fluorescence Plate Reader.

Macrophages are at the center of innate immunity and are the main target cells of the intracellular pathogen Salmonella enterica serovar Typhi. The production of reactive oxygen and nitrogen species (ROS/RNS) is the host's early response to invading microbes, as oxidative stress is highly toxic for bacteria. Adequate ROS/RNS production in infected macrophages is critical for the clearance of intracellular pathogens; this is achieved by several enzymes, including inducible NADPH phagocyte oxidase (NOX) and nitric oxide synthase (iNOS), respectively. The pro-inflammatory cytokine interferon gamma (IFNγ), primarily produced by activated natural killer cells and T-helper cells type 1, is a potent inducer of iNOS. Therefore, it is crucial for infection control through oxidative microbicidal activity. To characterize the early oxidative stress response via ROS formation, which is critical for the reduction of Salmonella proliferation within macrophages, we established an in vitro model of murine macrophages infected with Salmonella enterica serovar Typhimurium (S.tm). This serovar induces a systemic infection in mice that is frequently used as a model for typhoid fever, which, in human subjects, is caused by Salmonella Typhi. We generated bone marrow-derived macrophages (BMDM) from C57BL/6N wildtype mice using macrophage colony-stimulating factor (M-CSF) stimulation for six days. Thereafter, we infected BMDM withS. tm for one hour. Shortly before infection, cells were stained with CellROXTM Deep Red reagent. In its reduced form, CellROXTM is non-fluorescent. As a result of oxidation by ROS, this reagent exhibits strong fluorescence and persists within the cells. Subsequently, changes as a result of the oxidative stress response can be measured with a TECAN Spark microplate reader over time. We designed this protocol to measure oxidative stress in macrophages through the course of an infection with an intracellular bacterium. The protocol has several advantages over established techniques. First, it allows to continuously monitor and quantify ROS production in living cells from the very start of the infection to the final clearance of the intracellular pathogen. Second, this protocol enables efficient ROS detection without stressing the cells by detaching or staining procedures. Graphical abstract.

Role of IL-22 in acute asthma mouse model

Introduction: Allergic asthma is often associated with eosinophilic inflammation, which is related to the T-helper cell type 2 (Th2) cytokines and responsive to corticosteroids. However, there are also phenotypes of non-Th2-mediated asthma, which have poor responsivity to corticosteroids. The leading phenotype of non-Th2-mediated asthma is neutrophilic asthma, which is considered difficult to treat. Recently, IL-22 has been found to be involved in neutrophilic inflammation in asthma. However, studies on the role of IL-22 in asthma are still controversial as IL-22 has both pro-inflammatory and anti-inflammatory roles in asthma. This study examined whether the IL-22 level increased in acute neutrophilic asthma in the mouse model. Herein, we aimed to demonstrate increased IL-22 levels in neutrophilic asthma and elucidate the pathways leading to elevated neutrophil counts.Methods: Six-week old female BALB/c mice were sensitized and challenged with PBS, ovalbumin (OVA) or OVA + lipopolysaccharide (LPS). The mice were then assigned to one of the following five groups: (1) control (PBS/ PBS), (2) OVA/PBS, (3) OVA/OVA, (4) OVA+LPS/PBS, (5) OVA+LPS/OVA+LPS.Results: The levels of Th2 cytokines, IL-17, and IL-22 were assessed, with investigation of the neutrophil chemokines. This study showed that in the acute neutrophilic asthma, the levels of IL-17 and IL-22 were significantly higher than those in the OVA/OVA group, which represents acute eosinophilic asthma. Moreover, the level of CCL20 increased in the neutrophilic asthma group.Conclusion: Thus, this study suggests that in the acute neutrophilic asthma mouse model, IL-17 and IL-22 may increase with CCL20, resulting in neutrophilic inflammation.

130 Skin-associated side effects in patients with chronic rhinosinusitis with nasal polyposis following treatment with dupilumab

Chronic rhinosinusitis with nasal polyposis (CRSwNP) is a typical type-2 inflammation involving T-helper type-2 cells and impairing quality of life due to nasal obstruction, discharge and reduced sense of smell. Recently, the anti-IL4Ra antibody dupilumab was approved for CRSwNP and while dermatologic side effects in patients treated with dupilumab for atopic dermatitis are frequently observed, there is limited knowledge about these effects in patients with CRSwNP. We aimed to investigate frequency and characteristics of dermatologic side effects following initiation of dupilumab treatment in a cohort of Austrian CRSwNP patients.

351 Development and characterization of an immune 3D model mimicking psoriasis

Psoriasis is a common chronic skin disease characterized by a pro-inflammatory environment mediated by keratinocytes and both innate and adaptative immune responses. This inflammation is mostly driven by the IL-17/IL-23 axis resulting in the production of inflammatory and immune factors (chemokines and antimicrobial peptides) by keratinocytes. These mediators lead to an amplification loop and consequently to an epidermal hyperplasia. To our knowledge, very few 3D skin models involving lymphocyte T-helper cell type 17 (LTh17) reproduce accurately psoriasis features.

MBD2 mediates Th17 cell differentiation by regulating MINK1 in Th17-dominant asthma.

Objectives: .Asthma is a highly heterogeneous disease, and T-helper cell type 17 (Th17) cells play a pathogenic role in the development of non-T2 severe asthma. Misshapen like kinase 1 (MINK1) is involved in the regulation of Th17 cell differentiation, but its effect on severe asthma remains unclear. Our previous studies showed that methyl-CpG binding domain protein 2 (MBD2) expression was significantly increased in patients with Th17 severe asthma and could regulate Th17 cell differentiation. The aim of this study was to investigate how MBD2 interacts with MINK1 to regulate Th17 cell differentiation in Th17-dominant asthma. Materials and methods: Female C57BL/6 mice and bronchial epithelial cells (BECs) were used to establish mouse and cell models of Th17-dominant asthma, respectively. Flow cytometry was used to detect Th17 cell differentiation, and the level of IL-17 was detected by enzyme-linked immunosorbent assay (ELISA). Western blot and quantitative real-time PCR (qRT-PCR) were used to detect MBD2 and MINK1 expression. To investigate the role of MBD2 and MINK1 in Th17 cell differentiation in Th17-dominant asthma, the MBD2 and MINK1 genes were silenced or overexpressed by small interfering RNA and plasmid transfection. Results: Mouse and BEC models of Th17-dominant asthma were established successfully. The main manifestations were increased neutrophils in BALF, airway hyperresponsiveness (AHR), activated Th17 cell differentiation, and high IL-17 levels. The expression of MBD2 in lung tissues and BECs from the Th17-dominant asthma group was significantly increased, while the corresponding expression of MINK1 was significantly impaired. Through overexpression or silencing of MBD2 and MINK1 genes, we have concluded that MBD2 and MINK1 regulate Th17 cell differentiation and IL-17 release. Interestingly, MBD2 was also found to negatively regulate the expression of MINK1. Conclusion: Our findings have revealed new roles for MBD2 and MINK1, and provide new insights into epigenetic regulation of Th17-dominant asthma, which is dominated by neutrophils and Th17 cells. This study could lead to new therapeutic targets for patients with Th17-dominant asthma.

CD109 on Dendritic Cells Regulates Airway Hyperreactivity and Eosinophilic Airway Inflammation.

Asthma is a chronic airway inflammatory disease characterized by airway hyperreactivity (AHR) and eosinophilic airway inflammation. Dendritic cells (DCs) are essential for the development of asthma via presenting allergens, causing T-helper cell type 2 (Th2) skewing and eosinophil inflammation. Recent studies have revealed that CD109, a glycosylphosphatidylinositol-anchored glycoprotein, is involved in the pathogenesis of inflammatory diseases such as rheumatoid arthritis and psoriasis. However, no study has addressed the role of CD109 in asthma. This study sought to address the role of CD109 on DCs in the development of AHR and allergic inflammation. CD109-deficient mice (CD109-/-) were sensitized with house dust mite or ovalbumin and compared with wild-type mice for induction of AHR and allergic inflammation. CD109-deficient mice had reduced AHR and eosinophilic inflammation together with lower Th2 cytokine expression compared with wild-type mice. Interestingly, CD109 expression was induced in lung conventional DC2s (cDC2s), but not lung cDC1s, upon allergic challenge. Lung cDC2s from CD109-/- mice had a poor ability to induce cytokine production in ex vivo DC-T cell cocultures with high expression of RUNX3 (runt-related transcription factor 3), resulting in suppression of Th2 differentiation. Adoptive transfer of bone marrow-derived CD109-/- DCs loaded with house dust mite failed to develop AHR and eosinophilic inflammation. Finally, administration of monoclonal anti-CD109 antibody reduced airway eosinophils and significantly decreased AHR. Our results suggest the involvement of CD109 in asthma pathogenesis. CD109 is a novel therapeutic target for asthma.