Evaluation of Th1/Th2, regulatory cytokines and transcriptional factor FoxP3 in sheep immunized with a partially protective and non-protective vaccine and challenged with Fasciola hepatica.

Gene expression for Th1/Th2 cytokines (IL-4 and IFN-É£), regulatory cytokines (TGF-ß and IL-10) and the transcriptional factor FoxP3 was analyzed in the liver and hepatic lymph nodes (HLN) from sheep immunized with partially protective and non-protective vaccine candidates and challenged with Fasciola hepatica. FoxP3 T cells were also evaluated by immunohistochemistry (IHQ). The most remarkable difference between the partially protected vaccinated (V1) group and the non-protected vaccinated (V2) group was a more severe expansion of FoxP3 T cells recorded by IHQ in both the liver and HLN of the V2 group as compared to the V1 group, whereas no differences were found between the V2 group and the infected control (IC) group. Similar results were recorded for FoxP3 gene expression although significant differences among V1 and V2 groups were only significant in the HLN, while FoxP3 gene expression was very similar in the V2 and IC groups both in the liver and HLN. No significant differences for the remaining cytokines were recorded between the V1 and V2 groups, but in the liver the V2 group shows significant increases of IFN-É£ and IL-10 as compared to the uninfected control (UC) group whereas the V1 group did not. The lower expansion of FoxP3 T cells and lower increase of IFN-É£ and IL-10 in the partially protected vaccinated group may be related with lower hepatic lesions and fluke burdens recorded in this group as compared to the other two infected groups. The most relevant change in regulatory cytokine gene expression was the significant increase of TGF-ß in the liver of IC, V1 and V2 groups as compared to the UC group, which could be related to hepatic lesions.

Mucosal immunization with a low-energy electron inactivated respiratory syncytial virus vaccine protects mice without Th2 immune bias.

The respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infections associated with numerous hospitalizations. Recently, intramuscular (i.m.) vaccines against RSV have been approved for elderly and pregnant women. Noninvasive mucosal vaccination, e.g., by inhalation, offers an alternative against respiratory pathogens like RSV. Effective mucosal vaccines induce local immune responses, potentially resulting in the efficient and fast elimination of respiratory viruses after natural infection. To investigate this immune response to an RSV challenge, low-energy electron inactivated RSV (LEEI-RSV) was formulated with phosphatidylcholine-liposomes (PC-LEEI-RSV) or 1,2-dioleoyl-3-trimethylammonium-propane and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DD-LEEI-RSV) for vaccination of mice intranasally. As controls, LEEI-RSV and formalin-inactivated-RSV (FI-RSV) were used via i.m. vaccination. The RSV-specific immunogenicity of the different vaccines and their protective efficacy were analyzed. RSV-specific IgA antibodies and a statistically significant reduction in viral load upon challenge were detected in mucosal DD-LEEI-RSV-vaccinated animals. Alhydrogel-adjuvanted LEEI-RSV i.m. showed a Th2-bias with enhanced IgE, eosinophils, and lung histopathology comparable to FI-RSV. These effects were absent when applying the mucosal vaccines highlighting the potential of DD-LEEI-RSV as an RSV vaccine candidate and the improved performance of this mucosal vaccine candidate.

Oral administration of egg ovalbumin allergen induces dysregulation of tryptophan metabolism in sensitized BALB/c mice.

Food allergy (FA), triggered by specific dietary allergens, has emerged as a substantial global concern for food safety and public health. While studies have elucidated changes in immune cells and cytokines associated with allergen exposure, a comprehensive analysis of the host's metabolic features and the interaction between metabolites and the gut microbiota has not been conducted. In this study, egg allergen ovalbumin (OVA) was administered by the oral route to sensitized BALB/c mice to faithfully replicate key aspects of human FA, including severe allergic diarrhea, mast cell infiltration, and elevated levels of serum IgE, mMCPT-1, and Th2 cell hallmark cytokines (such as IL-4, IL-5, and IL-13). Furthermore, the untargeted and targeted metabolomic analyses indicated that FA in mice precipitated a substantial decrease in the tryptophan metabolites indole-3-acrylic acid (IA) and indole-3-lactic acid (ILA). The integration of shotgun metagenome and metabolome data further unveiled that the dysregulation of indole metabolism is related to a decline in the abundance of beneficial bacteria such as Lactobacillus and Bifidobacterium. Additionally, disruption of the tryptophan indole derivative pathway compromises the maintenance of intestinal mucosal function through the AHR signaling pathway, manifested by decreased expression of Reg3g and IL22. Taken together, this study demonstrated that the anaphylaxis triggered by oral ingestion of food allergens can lead to disruptions in tryptophan metabolism, consequently impairing intestinal immune homeostasis.

Natural antibodies drive type 2 immunity in response to damage-associated molecular patterns.

Allergic airway disease (AAD) is an example of type 2 inflammation that leads to chronic airway eosinophilia controlled by CD4 Th2 cells. Inflammation is reinforced by mast cells and basophils armed with allergen-specific IgE made by allergen-specific B2 B cells of the adaptive immune system. Little is known about how AAD is affected by innate B1 cells, which produce natural antibodies (NAbs) that facilitate apoptotic cell clearance and detect damage- and pathogen-associated molecular patterns (DAMPS and PAMPS). We used transgenic mice lacking either B cells or NAbs in distinct mouse models of AAD that require either DAMPS or PAMPS as the initial trigger for type 2 immunity. In a DAMP-induced allergic model, driven by alum and uric acid, mouse strains lacking B cells (CD19DTA), NAbs (IgHEL MD4), or all secreted antibodies (sIgm-/-Aid-/-) displayed a significant reduction in both eosinophilia and Th2 priming compared with WT or Aid-/- mice lacking only germinal center-dependent high-affinity class-switched antibodies. Replenishing B cell-deficient mice with either unimmunized B1 B cells or NAbs during sensitization restored eosinophilia, suggesting that NAbs are required for licensing antigen-presenting cells to prime type 2 immunity. Conversely, PAMP-dependent type 2 priming to house dust mite or Aspergillus was not dependent on NAbs. This study reveals an underappreciated role of B1 B cell-generated NAbs in selectively driving DAMP-induced type 2 immunity.

A Multicenter Long-Term Cohort Study of Eosinophilic Esophagitis Variants and Their Progression to Eosinophilic Esophagitis Over Time.

INTRODUCTION: Eosinophilic esophagitis (EoE) variants have been recently characterized as conditions with symptoms of esophageal dysfunction resembling EoE, but absence of significant esophageal eosinophilia. Their disease course and severity have yet to be determined. METHODS: Patients from 6 EoE centers with symptoms of esophageal dysfunction, but peak eosinophil counts of <15/hpf in esophageal biopsies and absence of gastroesophageal reflux disease with at least one follow-up visit were included. Clinical, (immuno)histological, and molecular features were determined and compared with EoE and healthy controls. RESULTS: We included 54 patients with EoE variants (EoE-like esophagitis 53.7%; lymphocytic esophagitis 13.0%; and nonspecific esophagitis 33.3%). In 8 EoE-like esophagitis patients, EoE developed after a median of 14 months (interquartile range 3.6-37.6). Such progression increased over time (17.6% year 1, 32.0% year 3, and 62.2% year 6). Sequential RNA sequencing analyses revealed only 7 genes associated with this progression (with TSG6 and ALOX15 among the top 3 upregulated genes) with upregulation of a previously attenuated Th2 pathway. Immunostaining confirmed the involvement of eosinophil-associated proteins (TSG6 and ALOX15) and revealed a significantly increased number of GATA3-positive cells during progression, indicating a Th1/Th2 switch. Transition from one EoE variant (baseline) to another variant (during follow-up) was seen in 35.2% (median observation time of 17.3 months). DISCUSSION: Transition of EoE variants to EoE suggests the presence of a disease spectrum. Few genes seem to be associated with the progression to EoE with upregulation of a previously attenuated Th2 signal. These genes, including GATA3 as a Th1/Th2 switch regulator, may represent potential therapeutic targets in early disease pathogenesis.

Eosinophils Are an Endogenous Source of Interleukin-4 during Filarial Infections and Contribute to the Development of an Optimal T Helper 2 Response.

INTRODUCTION: Interleukin-4 (IL-4) is a central regulator of type 2 immunity, crucial for the defense against multicellular parasites like helminths. This study focuses on its roles and cellular sources during Litomosoides sigmodontis infection, a model for human filarial infections. METHODS: Utilizing an IL-4 secretion assay, investigation into the sources of IL-4 during the progression of L. sigmodontis infection was conducted. The impact of eosinophils on the Th2 response was investigated through experiments involving dblGATA mice, which lack eosinophils and, consequently, eosinophil-derived IL-4. RESULTS: The absence of eosinophils notably influenced Th2 polarization, leading to impaired production of type 2 cytokines. Interestingly, despite this eosinophil deficiency, macrophage polarization, proliferation, and antibody production remained unaffected. CONCLUSION: Our research uncovers eosinophils as a major source of IL-4, especially during the early phase of filarial infection. Consequently, these findings shed new light on IL-4 dynamics and eosinophil effector functions in filarial infections.

SAA suppresses α-PD-1 induced anti-tumor immunity by driving TH2 polarization in lung adenocarcinoma.

Cancer stem cells (CSCs) are believed to be crucial in the initiation, progression, and recurrence of cancer. CSCs are also known to be more resistant to cancer treatments. However, the interaction between CSCs and the immune microenvironment is complex and not fully understood. In current study we used single cell RNA sequence (scRNA-Seq, public dataset) technology to identify the characteristic of CSCs. We found that the lung adenocarcinoma cancer stem population is highly inflammatory and remodels the tumor microenvironment by secreting inflammatory factors, specifically the acute phase protein serum amyloid A (SAA). Next, we developed an ex-vivo autologous patient-derived organoids (PDOs) and peripheral blood mononuclear cells (PBMCs) co-culture model to evaluate the immune biological impact of SAA. We found that SAA not only promotes chemoresistance by inducing cancer stem transformation, but also restricts anti-tumor immunity and promotes tumor fibrosis by driving type 2 immunity, and α-SAA neutralization antibody could restrict treatment resistant and tumor fibrosis. Mechanically, we found that the malignant phenotype induced by SAA is dependent on P2X7 receptor. Our data indicate that cancer stem cells secreted SAA have significant biological impact to promote treatment resistant and tumor fibrosis by driving cancer stemness transformation and type 2 immunity polarization via P2X7 receptor. Notably, α-SAA neutralization antibody shows therapeutic potential by restricting these malignant phenotypes.

Mast cells link immune sensing to antigen-avoidance behaviour.

The physiological functions of mast cells remain largely an enigma. In the context of barrier damage, mast cells are integrated in type 2 immunity and, together with immunoglobulin E (IgE), promote allergic diseases. Allergic symptoms may, however, facilitate expulsion of allergens, toxins and parasites and trigger future antigen avoidance1-3. Here, we show that antigen-specific avoidance behaviour in inbred mice4,5 is critically dependent on mast cells; hence, we identify the immunological sensor cell linking antigen recognition to avoidance behaviour. Avoidance prevented antigen-driven adaptive, innate and mucosal immune activation and inflammation in the stomach and small intestine. Avoidance was IgE dependent, promoted by Th2 cytokines in the immunization phase and by IgE in the execution phase. Mucosal mast cells lining the stomach and small intestine rapidly sensed antigen ingestion. We interrogated potential signalling routes between mast cells and the brain using mutant mice, pharmacological inhibition, neural activity recordings and vagotomy. Inhibition of leukotriene synthesis impaired avoidance, but overall no single pathway interruption completely abrogated avoidance, indicating complex regulation. Collectively, the stage for antigen avoidance is set when adaptive immunity equips mast cells with IgE as a telltale of past immune responses. On subsequent antigen ingestion, mast cells signal termination of antigen intake. Prevention of immunopathology-causing, continuous and futile responses against per se innocuous antigens or of repeated ingestion of toxins through mast-cell-mediated antigen-avoidance behaviour may be an important arm of immunity.

Exposure to violence and asthma in Puerto Rican youth with high Th2 immunity.

BACKGROUND: Little is known about the determinants of asthma among youth with high T helper 2 (Th2) immunity. We hypothesized that exposure to violence (ETV) and violence-related distress are associated with asthma in children and adolescents with high Th2 immunity. METHODS: We analyzed data from Puerto Ricans with high Th2 immunity aged 9-20 years in the Puerto Rico Genetics of Asthma and Lifestyle (PR-GOAL) and the Epigenetic Variation of Childhood Asthma in Puerto Ricans (EVA-PR) studies, and in a prospective study (PROPRA). High Th2-immunity was defined as ≥1 positive allergen-specific IgE and/or a total IgE ≥ 100 IU/mL and/or an eosinophil count ≥ 150 cells/µL. Asthma was defined as physician-diagnosed asthma and current wheeze. ETV and violence-related distress were assessed with the validated ETV Scale and Checklist of Children's Distress Symptoms (CCDS) questionnaires, respectively. RESULTS: In multivariable analyses, each 1-point increment in ETV score was significantly associated with 1.13-1.17 times increased odds of asthma in PR-GOAL and in EVA-PR (both at p ≤ 0.01), and each 1-point increment in CCDS score was significantly associated with 1.53-1.54 increased odds of asthma in PR-GOAL and in EVA-PR (both at p ≤ 0.03). Further, a persistently high ETV score was significantly associated with asthma in PROPRA (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 1.10-7.29). Similar results were obtained in a sensitivity analysis using an eosinophil count ≥ 300 cells/µL instead of ≥150 cells/µL to define high Th2 immunity. CONCLUSIONS: ETV during childhood is associated with increased risk of persistent or new-onset asthma in youth with high Th2 immunity.

IL2RB affects Th1/Th2 and Th17 responses of peripheral blood mononuclear cells from septic patients

Background: Immune dysfunction is a common and serious complication of sepsis. This study finds key genes linked to immunity in sepsis. Methods: The “Limma package” was used to analyze GSE154918 datasets for differentially expressed genes. The differentially expressed genes were then enriched for Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and interleukin 2 receptor subunit Beta (IL2RB) protein coding gene was chosen for investigation. IL2RB expression in peripheral blood mononuclear cells (PBMC) was assessed by polymerase chain reaction. White blood cells of septic patients and healthy controls were collected from hospitals and linked with acute physiology and chronic health evaluation (APACHE) II, sequential organ failure assessment (SOFA), C-reactive protein (CRP), and procalcitonin (PCT) of septic patients using Pearson’s correlation analysis. PBMC cells were transfected with IL2RB, and the effect of transfection was observed on cellular interferon gamma (IFN-γ), interleukin (IL)-12, IL-4, IL-10, and IL-17A. Results: A total of 686 differential genes, comprising 446 upregulated and 240 down regulated genes, were identified. The enrichment of KEGG pathway revealed that the majority of differential genes were enriched in the T helper (Th1)/Th2 cell and Th17 cell differentiation pathways. In patients with sepsis, correlation analysis revealed a negative correlation between IL2RB and APACHE II score, SOFA score, CRP, and PCT. IFN-γ and IL-12 levels were elevated in PBMC of septic patients after IL2RB transfection, but IL-4, IL-10, and IL-17A levels were lowered. Conclusion: Sepsis-induced immunological dysfunction is improved by IL2RB, which also balances Th1/Th2 responses and prevents Th17 activation. © 2023 Codon Publications. Published by Codon Publications (AU)

Metabolism in type 2 immune responses.

The immune response is tailored to the environment in which it takes place. Immune cells sense and adapt to changes in their surroundings, and it is now appreciated that in addition to cytokines made by stromal and epithelial cells, metabolic cues provide key adaptation signals. Changes in immune cell activation states are linked to changes in cellular metabolism that support function. Furthermore, metabolites themselves can signal between as well as within cells. Here, we discuss recent progress in our understanding of how metabolic regulation relates to type 2 immunity firstly by considering specifics of metabolism within type 2 immune cells and secondly by stressing how type 2 immune cells are integrated more broadly into the metabolism of the organism as a whole.

LINC00632 relates to milder Th1/Th2 imbalance, attenuated nasal symptoms, and better response to therapy in allergic rhinitis patients

Objective: Long intergenic noncoding RNA 00632 (LINC00632) regulates nasal inflammation and CD4+ T cell differentiation into T helper (Th) 2 cells in allergic rhinitis (AR). This study aimed to explore the relationship between LINC00632 and Th1/Th2 balance, and the clinical value of LINC00632 in AR patients. Methods: In total, 120 AR patients, 20 non-atopic obstructive snoring patients as disease controls (DCs), and 20 healthy controls (HCs) were recruited. Their LINC00632 expressions in peripheral blood mononuclear cells were detected by RT-qPCR. Results: LINC00632 expression was declined in AR patients compared with DCs and HCs (both P ˂ 0.001). Moreover, LINC00632 could distinguish AR patients from DCs with an area under curve (AUC) of 0.795 (95% confidence interval [CI]: 0.701–0.889), and from HCs with an AUC of 0.895 (95%CI: 0.831–0.960). LINC00632 was positively related to Th1 cells (P = 0.037) and Th1/Th2 axis (P ˂ 0.001) in AR patients. In addition, LINC00632 was inversely associated with Th2 cells (P ˂ 0.001) and interleukin (IL)-4 (P = 0.010) in AR patients. Besides, LINC00632 was negatively related to rhinorrhea score (P = 0.019), itching score (P = 0.008), sneezing score (P = 0.004), and total nasal symptom score (TNSS) (P ˂ 0.001), but no correlation between LINC00632 and congestion score was observed (P = 0.093). During treatment, LINC00632 was elevated, while TNSS score was reduced (both P ˂ 0.001). Furthermore, LINC00632 increment was associated with the reduction of TNSS score during the therapy (P = 0.005). Conclusion: LINC00632 relates to milder Th1/Th2 imbalance, attenuated nasal symptoms, and better response during 4-week therapy in AR patients (AU)

Correlation between B-cell lymphoma 6 with the balance of T helper-1/2 and severity of allergic rhinitis

Objective: Allergic rhinitis (AR) is a prevailing immune disorder affecting the nasal mucosa. B-cell lymphoma 6 (BCL6) imposes essential roles in immunity. This study probed into the serum expression of BCL6 and its effect on AR diagnosis and patients’ quality of life (QOL). Methods: A total of 113 patients with AR including 38 cases with mild AR (MAR) and 75 cases with moderate-severe AR (MSAR) were enrolled, with 101 healthy people enrolled as control. Serum expression of BCL6 was detected by RT-qPCR and the diagnostic efficacy of BCL6 for AR was analyzed using the receiver operating characteristic curve. The proportion of T helper-1/2 (Th1/Th2) cells in CD4+ T cells in peripheral blood mononuclear cells was detected using flow cytometry. The correlation between BCL6 and Th1/Th2 cells and the effects of BCL6 expression on patients’ QOL were assessed by Pearson analysis and Mini-RQLQ questionnaire. Results: BCL6 was downregulated in patients with AR, serum BCL6 level < 0.8450 had certain auxiliary diagnostic values for AR, and serum BCL6 level < 0.5400 could assist the diagnosis of AR severity. Th1 cell proportion in CD4+ T cells was decreased, whereas Th2 cell proportion was increased with AR severity. BCL6 was positively-linked with Th1 cells but inversely-correlated with Th2 cells in patients with AR. Patients with AR with low BCL6 expression had a poorer QOL compared with high BCL6 expression. The domains most affected by BCL6 expression were practical problems, nasal symptoms, and lacrimation. Conclusion: Serum BCL6 is downregulated and low BCL6 expression greatly deteriorates QOL in patients with AR (AU)

MALT1 regulates Th2 and Th17 differentiation via NF-κB and JNK pathways, as well as correlates with disease activity and treatment outcome in rheumatoid arthritis.

Objective: MALT1 regulates immunity and inflammation in multiple ways, while its role in rheumatoid arthritis (RA) is obscure. This study aimed to investigate the relationship of MALT1 with disease features, treatment outcome, as well as its effect on Th1/2/17 cell differentiation and underlying molecule mechanism in RA. Methods: Totally 147 RA patients were enrolled. Then their blood Th1, Th2, and Th17 cells were detected by flow cytometry. Besides, PBMC MALT1 expression was detected before treatment (baseline), at week (W) 6, W12, and W24. PBMC MALT1 in 30 osteoarthritis patients and 30 health controls were also detected. Then, blood CD4+ T cells were isolated from RA patients, followed by MALT1 overexpression or knockdown lentivirus transfection and Th1/2/17 polarization assay. In addition, IMD 0354 (NF-κB antagonist) and SP600125 (JNK antagonist) were also added to treat CD4+ T cells. Results: MALT1 was increased in RA patients compared to osteoarthritis patients and healthy controls. Meanwhile, MALT1 positively related to CRP, ESR, DAS28 score, Th17 cells, negatively linked with Th2 cells, but did not link with other features or Th1 cells in RA patients. Notably, MALT1 decreased longitudinally during treatment, whose decrement correlated with RA treatment outcome (treatment response, low disease activity, or disease remission). In addition, MALT1 overexpression promoted Th17 differentiation, inhibited Th2 differentiation, less affected Th1 differentiation, activated NF-κB and JNK pathways in RA CD4+ T cells; while MALT1 knockdown exhibited the opposite effect. Besides, IMD 0354 and SP600125 addition attenuated MALT1's effect on Th2 and Th17 differentiation. Conclusion: MALT1 regulates Th2 and Th17 differentiation via NF-κB and JNK pathways, as well as correlates with disease activity and treatment outcome in RA.

Distinct spatial and temporal roles for Th1, Th2, and Th17 cells in asthma.

Immune response in the asthmatic respiratory tract is mainly driven by CD4+ T helper (Th) cells, represented by Th1, Th2, and Th17 cells, especially Th2 cells. Asthma is a heterogeneous and progressive disease, reflected by distinct phenotypes orchestrated by τh2 or non-Th2 (Th1 and Th17) immune responses at different stages of the disease course. Heterogeneous cytokine expression within the same Th effector state in response to changing conditions in vivo and interlineage relationship among CD4+ T cells shape the complex immune networks of the inflammatory airway, making it difficult to find one panacea for all asthmatics. Here, we review the role of three T helper subsets in the pathogenesis of asthma from different stages, highlighting timing is everything in the immune system. We also discuss the dynamic topography of Th subsets and pathogenetic memory Th cells in asthma.

Suppression of Allergic Asthma by Loss of Function of Miz1-mediated Th1 Skewing.

Asthma is the most prevalent chronic respiratory disease worldwide. There is currently no cure, and it remains an important cause of morbidity and mortality. Here we report that lung-specific loss of function of the transcription factor Miz1 (c-Myc-interacting zinc finger protein-1) upregulates the pro-T-helper cell type 1 cytokine IL-12. Upregulation of IL-12 in turn stimulates a Th1 response, thereby counteracting T-helper cell type 2 response and preventing the allergic response in mouse models of house dust mite- and OVA (ovalbumin)-induced asthma. Using transgenic mice expressing Cre under a cell-specific promoter, we demonstrate that Miz1 acts in lung epithelial cells and dendritic cells in asthma. Chromatin immunoprecipitation coupled with high-throughput DNA sequencing or quantitative PCR reveals the binding of Miz1 on the Il12 promoter indicating direct repression of IL-12 by Miz1. In addition, HDAC1 (histone deacetylase 1) is recruited to the Il12 promoter in a Miz1-depdenent manner, suggesting epigenetic repression of Il12 by Miz1. Furthermore, Miz1 is upregulated in the lungs of asthmatic mice. Our data together suggest that Miz1 is upregulated during asthma, which in turn promotes asthma pathogenesis by preventing Th1 skewing through the transcriptional repression of IL-12.

lncRNA FR215775 Regulates Th2 Differentiation in Murine Allergic Rhinitis.

To identify the effect of long noncoding RNA (lncRNA) FR215775 in regulating CD4+ T cells on murine models of allergic rhinitis (AR), the expression of lncRNA FR215775 in primary Th2 cells was detected through qRT-PCR. After knocking down the expression of lncRNA FR215775 via Sh-FR215775-Ads, Cell Counting Kit-8, cytometric bead array, and fluorescence-activated cell sorting were performed to determine its functions in vitro. Moreover, lncRNA FR215775-silencing or nonsilencing cells were injected intravenously into AR mice. Then, hematoxylin and eosin, Alcian blue-periodic acid Schiff, and toluidine blue staining were performed, and the levels of IL-2, IL-4, IL-5, IL-6, IL-10, IL-17A, IFN-γ, and TNF in the AR mice were also determined. We found that the expression of lncRNA FR215775 was specifically higher in the murine primary Th2 cells. After the knockdown of lncRNA FR215775, the proliferation of CD4+ T cells was inhibited, and the expressions of IL-4 and IL-5 in the cell culture supernatant were significantly decreased (P < 0.001), along with the percentage of Th2 cells (P < 0.05). The lncRNA FR215775-silencing AR group showed less serious allergic symptoms and a low level of ovalbumin-specific immunoglobulin E (P < 0.01). Meanwhile, the eosinophilia inflammation, goblet cell hyperplasia, and mast cell inflammation in the nasal mucosa all decreased, which indicated attenuated allergic inflammation in the lncRNA FR215775-silencing AR group. In addition, the Th2-related cytokines IL-4 and IL-5 were downregulated in the serum and nasal lavage fluid of this group (P < 0.01). In conclusion, lncRNA FR215775 may play a vital role in the function and differentiation of Th2 cells, which may encourage allergic inflammation. These results may provide significant insights into AR pathogenesis and offer new treatment targets for alleviating AR.

Ablation of cDC2 development by triple mutations within the Zeb2 enhancer.

The divergence of the common dendritic cell progenitor1-3 (CDP) into the conventional type 1 and type 2 dendritic cell (cDC1 and cDC2, respectively) lineages4,5 is poorly understood. Some transcription factors act in the commitment of already specified progenitors-such as BATF3, which stabilizes Irf8 autoactivation at the +32 kb Irf8 enhancer4,6-but the mechanisms controlling the initial divergence of CDPs remain unknown. Here we report the transcriptional basis of CDP divergence and describe the first requirements for pre-cDC2 specification. Genetic epistasis analysis7 suggested that Nfil3 acts upstream of Id2, Batf3 and Zeb2 in cDC1 development but did not reveal its mechanism or targets. Analysis of newly generated NFIL3 reporter mice showed extremely transient NFIL3 expression during cDC1 specification. CUT&RUN and chromatin immunoprecipitation followed by sequencing identified endogenous NFIL3 binding in the -165 kb Zeb2 enhancer8 at three sites that also bind the CCAAT-enhancer-binding proteins C/EBPα and C/EBPß. In vivo mutational analysis using CRISPR-Cas9 targeting showed that these NFIL3-C/EBP sites are functionally redundant, with C/EBPs supporting and NFIL3 repressing Zeb2 expression at these sites. A triple mutation of all three NFIL3-C/EBP sites ablated Zeb2 expression in myeloid, but not lymphoid progenitors, causing the complete loss of pre-cDC2 specification and mature cDC2 development in vivo. These mice did not generate T helper 2 (TH2) cell responses against Heligmosomoides polygyrus infection, consistent with cDC2 supporting TH2 responses to helminths9-11. Thus, CDP divergence into cDC1 or cDC2 is controlled by competition between NFIL3 and C/EBPs at the -165 kb Zeb2 enhancer.

Livin promotes Th2-type immune response in airway allergic diseases.

OBJECTIVES: To investigate the effects of livin on the Th2 immune response in airway allergic diseases (AAD) and explore the interaction among livin, GATA3, IL-4 in peripheral blood CD4+ T cells of AAD patients. METHODS: WT mice and livin KO mice were developed for model of AAD. Th2 cell levels in the lung tissues and spleen were assessed by flow cytometry. Also, it was assessed in the culture after exposing to livin inhibitor (Lp-15); the protein and mRNA levels of livin, GATA3 and IL-4 in peripheral blood CD4+ T cells isolated from patients with or without AAD were measured by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Finally, Co-immunoprecipitation (Co-IP) was employed to identify the interaction between livin and GATA3. RESULTS: Compared with WT mouse, Th2 cell frequency in lung tissues and spleen was significantly decreased in livin KO mouse; after adding Lp-15, the differentiation from Naive CD4+T cells in spleen to Th2 cells was blocked; the protein and mRNA levels of livin, GATA3 and IL-4 in AAD group were higher than that in control group. The levels of livin were positively correlated with IL-4, and GATA3 was also positively correlated with IL-4 and livin. GATA3 was detected in the protein complex co-precipitated with livin antibody, and livin was also detected in the protein complex co-precipitated by GATA3 antibody. CONCLUSION: Livin increases the expression of IL-4 and facilitates naive CD4+ T cells to differentiate into Th2 cells, which triggers airway allergy.

ADAMTS7 Attenuates House Dust Mite-Induced Airway Inflammation and Th2 Immune Responses.

PURPOSE: ADAMTS7 is a secreted metalloproteinase enzyme and proteoglycan associated with the early progression of coronary artery disease. However, there is limited information regarding the role of ADAMTS7 in lung adaptive immunity and inflammation. Thus, we sought to assess whether ADAMTS7 expression in the lung modulates house dust mite (HDM)-induced airway inflammation and Th2 immune response. METHODS: The role of ADAMTS7 in HDM-induced airway disease was assessed in ADAMTS7-deficient (ADAMTS7-/-) mice and compared with the wild-type control mice by flow cytometry, ELISA, and histopathology. Furthermore, the antigen priming capability of dendritic cells (DC) was determined ex vivo by employing coculture with CD4+ OT-II cells. RESULTS: ADAMTS7-/- mice develop an augmented eosinophilic airway inflammation, mucous cell metaplasia, and increased Th2 immune response to inhaled HDM. In addition, allergen uptake by lung DC and migration to draining mediastinal lymph node were significantly increased in ADAMTS7-/- mice, which shows an enhanced capacity to mount allergen-specific T-cell proliferation and effector Th2 cytokine productions. We propose that the mechanism by which ADAMTS7 negatively regulates DC function involves attenuated antigen uptake and presentation capabilities, which reduces allergic sensitization and Th2 immune responses in the lung. CONCLUSION: In aggregate, we provide compelling evidence that ADAMTS7 plays a pivotal role in allergic airway disease and Th2 immunity and would be an attractive target for asthma.