Engineering the IL-4/IL-13 axis for targeted immune modulation

Yinqiao antipruritic formula attenuates atopic dermatitis-like skin lesions through modulating the cytokine-cytokine receptor interaction pathway

Yinqiao Antipruritic Formula (YQAF) is a traditional Chinese medicine (TCM) formula for treating atopic dermatitis (AD) that has been used by the Huzhou Traditional Chinese Medicine Hospital in long-term clinical practice. It has definite therapeutic effects and minimal toxic side effects. However, the specific mechanism underlying the therapeutic effects of YQAF on AD remains ambiguous. We demonstrated the therapeutic effect of YQAF on Th2 type inflammation in a 2,4-dinitrochlorobenzene (DNCB)-induced AD mice model and elucidated the underlying mechanism. Results showed that YQAF effectively ameliorated the AD-like skin damage. YQAF suppressed the abnormal thickening of the epidermal hyperplasia induced by DNCB, decreased the mast cells infiltration, the collagen fibres number in the skin lesions, and reduced the expression of tumor necrosis factor-α (TNF-α), thymic stromal lymphopoietin (TSLP), interleukin (IL)-6 and nuclear factor kappa B (NF-κB). YQAF inhibited the Th2-type immune response, decreased the percentages of Th2 cells in dLNs, reduced the infiltration of group 2 innate lymphoid cells (ILC2), and suppressed the expression of IL-4 and IL-13 in skin lesions. According to the transcriptome sequencing results, YQAF inhibited the cytokine-cytokine interaction pathways. Our findings indicated that YQAF improved the symptoms of DNCB-induced AD-like lesions, which may be related to the inhibition of cytokine-cytokine interaction pathways. This indicated the potential of YQAF as a traditional Chinese Medicine formula for the treatment of AD.

Stage-Specific Immune Responses to AgB T-Peptides in Patients with Cystic Echinococcosis

Background: The identification of parasite- and stage-specific antigens is crucial for the development of new diagnostic tests for cystic echinococcosis (CE). We previously analysed the interleukin (IL)-4 response to T-specific peptides corresponding to the immunogenic regions of the five antigen B (AgB) subunits, demonstrating that AgB1 is the most immunogenic protein and that the response to all AgB peptides is associated with viable cysts. However, the response in patients with CE3a (WHO-IWGE) cystic stage was not evaluated and no other immunological factors besides IL-4 were included in the analysis. Methods: Four study groups were defined: "CE3a group" (transitional cysts), "CE3b group" (active cysts), "CE4/CE5 group" (inactive cysts), and "NO CE-group" encompassing patients with non-CE cysts (controls). Whole blood was stimulated in vitro with the five different T-specific peptide pools corresponding to the five AgB subunits and with a pool containing all five peptides' pools (total pool). IL-4 and other immunological markers were evaluated by ELISA and a multiplex assay, respectively. Results: Twenty-four patients with CE (CE3a-group n = 3; CE3b-group n = 6; CE4/CE5-group n = 15) and 14 subjects with non-CE cysts were enrolled. IL-4 levels in response to AgB1 and AgB3 pools were significantly increased in CE compared to NO CE groups (p = 0.0201, p = 0.0041). Within the CE patients, the highest IL-4 median level was observed in response to the AgB total pool, the AgB3 and AgB4 pools, followed by the AgB1 pool. Moreover, the IL-4 levels in response to the AgB1 pool were found to be significantly higher in the CE3b group compared to the CE4/CE5 group (p = 0.0070), while no differences were found for the CE3a group. As for other cytokines, we found higher IL-7 levels in response to the AgB4 pool in the CE4/CE5 group compared to the CE3b group (p = 0.0012), higher IL-2 levels in response to the AgB1 pool and AgB total pool in CE3b patients compared to controls (p = 0.0016), and higher IL-13 levels in response to the AgB total pool in patients with CE3b and CE4/CE5 cysts compared to NO CE (p = 0.0016; p = 0.0009). Conclusions: These results contribute to a better knowledge of the immune interplay in the presence of CE and may be useful for further exploring the use of recombinant proteins/peptides in cytokine release assays for the diagnosis and follow-up of CE.

Oral treatment with Rosa multiflora fructus extract modulates mast cells in canine atopic dermatitis

Introduction

Canine atopic dermatitis is a hereditary, often pruritic, and predominantly T-cell-driven inflammatory skin disease involving an interplay between skin barrier abnormalities and allergen sensitization. However, progress in developing therapeutics for companion animals remains slow, with few drugs advancing to Phase II clinical trials to investigate the underlying mechanisms in target animals. While Rosa multiflora fruit extract (RMFE) has been strongly implicated in the improvement of various inflammatory diseases, its effects on canine atopic dermatitis (cAD) and the putative underlying mechanisms remain unclear. In this study, we aimed to evaluate the efficacy of RMFE in the treatment of cAD and explore its underlying mechanisms.

Methods

In this study, RMFE was administered orally (repeatedly for 2 weeks) to ovalbumin (OVA)-induced atopic dermatitis-induced beagles. The effects of RMFE on cAD were assessed through clinical symptom observation and scoring using the canine atopic dermatitis extent and severity index. Additionally, histopathological analysis was performed (hematoxylin and eosin, Masson's trichrome, and toluidine blue). Cluster of differentiation 4-positive immunostaining was also performed, along with cytokine level and messenger ribonucleic acid level analyses of T-helper 2 (Th2) immune and inflammatory response markers in the modeled skin.

Results

RMFE improved the clinical manifestations of cAD, leading to histopathological modulation of inflammation and immune cells. It also altered Th2 effector cytokine levels. Furthermore, RMFE reduced allergic responses in the AD model dogs by reducing mast cell numbers, inhibiting their activation to release inflammatory mediators, and reducing immunoglobulin E (IgE) production.

Discussion

Our results suggest that RMFE can modulate mast cell activation and Th2-dominant immune responses in cAD, helping to reduce AD-induced inflammatory responses.

Altered Circulating Cytokine Profile Among mRNA-Vaccinated Young Adults: A Year-Long Follow-Up Study

OBJECTIVES

This longitudinal study aimed to assess the impact of COVID-19 vaccination on cytokine profile.

METHODS

A total of 84 Saudi subjects (57.1% females) with mean age of 27.2 ± 12.3 participated in this longitudinal study. Anthropometric data and fasting blood samples were obtained at baseline and after final vaccination, with an average follow-up duration of 14.1 ± 3.6 months for adolescents and 13.3 ± 3.0 months for adults, calculated from the first dose of vaccination. Assessment of cytokine profiles was done using commercially available assays.

RESULTS

After follow-up, a significant increase in weight and body mass index was observed overall (p = 0.003 and p = 0.002, respectively). Postvaccination, significant increases were observed in several cytokines, including basic fibroblast growth factor 2 (p < 0.001), interferon gamma (IFNγ) (p = 0.005), interleukin-1 beta (IL1β) (p < 0.001), IL4 (p < 0.001), IL6 (p = 0.003), IL7 (p = 0.001), IL17E (p < 0.001), monocyte chemoattractant protein-1 (MCP1) (p = 0.03), MCP3 (p = 0.001), tumor necrosis factor alpha (TNFα) (p < 0.001), and VEGFA (p < 0.001). A significant reduction was observed only in macrophage colony-stimulating factor (p < 0.001). When adjusted for age, epidermal growth factor (EGF), IL4, IL6, MCP3, TNFα, and vascular endothelial growth factor (VEGFA) remained statistically significant. Gender-based analysis revealed that men experienced greater increases in IL6 (p = 0.008), IL4 (p = 0.04), and TNFα (p = 0.015) compared to women. Age-based analysis showed that older participants had more pronounced increases in EGF (p = 0.011), IL6 (p = 0.029), MCP1 (p = 0.042), and TNFα (p = 0.017), while younger participants had a greater increase in VEGFA (p = 0.025).

CONCLUSIONS

The findings of this study indicated that COVID-19 vaccination resulted in an increase in cytokine levels, which signifies the persistence of the humoral immune response to messenger RNA (mRNA) vaccines. This effect may be attributed to the persistent production of spike protein and highly inflammatory nature of mRNA-lipid nanoparticle. Additionally, the results suggested differences in cytokine levels based on gender and age. Notably, the cytokine profile remains favorably altered in young adults who received mRNA vaccinations, even after 1 year.

GATA3-Driven ceRNA Network in Lung Adenocarcinoma Bone Metastasis Progression and Therapeutic Implications

Background/Objectives: Bone metastasis is a common and severe complication of lung adenocarcinoma (LUAD), impacting prognosis and treatment outcomes. Understanding the molecular mechanisms behind LUAD bone metastasis (LUADBM) is essential for developing new therapeutic strategies. The interactions between long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and mRNAs in the competing endogenous RNA (ceRNA) network are crucial in cancer progression and metastasis, but the regulatory mechanisms in LUADBM remain unclear. Methods: Microarray analysis was performed on clinical samples, followed by weighted gene co-expression network analysis (WGCNA) and construction of a ceRNA network. Molecular mechanisms were validated using colony formation assays, transwell migration assays, wound healing assays to assess cell migration, and osteoclastogenesis assays to evaluate osteoclast differentiation. Potential therapeutic drugs and their binding affinities were predicted using the CMap database and Kdeep. The interaction between the small-molecule drug and its target protein was confirmed by surface plasmon resonance (SPR) and drug affinity responsive target stability (DARTS) assays. Mechanistic insights and therapeutic efficacy were further validated using patient-derived organoid (PDO) cultures, drug sensitivity assays, and in vivo drug treatments. Results: Our results identified the XLOC_006941/hsa-miR-543/NPRL3 axis as a key regulatory pathway in LUADBM. We also demonstrated that GATA3-driven Th2 cell infiltration creates an immunosuppressive microenvironment that promotes metastasis. Additionally, we confirmed that the inhibitor E7449 effectively targets NPRL3, and its combination with the IL4R-blocking antibody dupilumab resulted in improved therapeutic outcomes in LUADBM. Conclusions: These findings offer new insights into the molecular mechanisms of LUADBM and highlight potential therapeutic targets, including the XLOC_006941/miR-543/NPRL3 axis and GATA3-driven Th2 cell infiltration. The dual-target therapy combining E7449 with dupilumab shows promise for improving patient outcomes in LUADBM, warranting further clinical evaluation.

Exploring the role of inflammatory biomarkers in trigeminal neuralgia

Background

Trigeminal neuralgia (TN) is a severe facial pain disorder with complex etiology. Inflammation has been suggested as a contributing factor to TN pathogenesis. This study investigates the causal relationship between inflammatory biomarkers, including 41 circulating inflammatory cytokines, C-reactive protein (CRP), and procalcitonin (PCT), and TN using Mendelian randomization (MR) analysis.

Methods

A two-sample MR approach was employed using genome-wide association study (GWAS) data from 8293 Finnish individuals for inflammatory cytokines and data from the FinnGen database for TN. Instrumental variables (IVs) were selected based on genome-wide significance and clumping thresholds to avoid linkage disequilibrium. Inverse variance weighting (IVW) was used as the primary method, complemented by MR Egger regression, weighted median, simple mode, and weighted mode methods. Additionally, Bayesian Weighted MR (BWMR) and Multivariable MR (MVMR) were utilized to validate the findings and explore potential confounders.

Results

The present MR analysis identified significant causal associations for three inflammatory cytokines with TN. Stem cell growth factor beta (SCGF-β) (OR = 1.362, 95% CI = 1.049-1.770, p = 0.021) and Interleukin-4 (IL-4) (OR = 1.533, 95% CI = 1.014-2.316, p = 0.043) were positively associated with TN, while Interleukin-16 (IL-16) (OR = 0.720, 95% CI = 0.563-0.921, p = 0.009) had a protective effect. CRP levels were also linked to TN risk (OR = 0.751, 95% CI = 0.593-0.951, p = 0.017). No significant causal effect of PCT on TN was observed. Sensitivity analyses confirmed the robustness of these findings, showing no evidence of horizontal pleiotropy or heterogeneity.

Conclusion

This study highlights specific inflammatory biomarkers that may play pivotal roles in TN pathogenesis. SCGF-β and IL-4 are potential therapeutic targets due to their facilitative effects on TN, while IL-16 could offer protective benefits. CRP's association with TN further supports the involvement of systemic inflammation in this condition. These findings provide novel insights into TN's inflammatory mechanisms, suggesting new avenues for targeted interventions.

Safety of dupilumab in Chinese pediatric patients aged 6 months and older: a prospective real-world study

Objective

This study analyzes the occurrence and characteristics of adverse drug reactions (ADRs) of dupilumab in children in a real-world setting. It aims to enhance clinical practice and minimize medication safety risks in pediatric patients.

Methods

This prospective study included children receiving dupilumab in the hospital between January 2022 and December 2023. Information on ADRs was collected and univariate and multivariate analyses were employed to identify high-risk factors for the occurrence of adverse effects in dupilumab treatment.

Results

A total of 65 ADRs occurred in 1,103 treatments in 127 patients, with an incidence of 27.56% (35/127). A total of 62 patients aged 6 or below participated in this study, accounting for 48.82%. Univariate analysis showed that gender, age, duration of medication, frequency of dupilumab use were risk factors for the occurrence of adverse effects (P < 0.05). Multivariate logistic regression analysis showed that age [odds ratio [OR]: 0.071, 95% confidence interval [CI]: 0.012-0.433; P = 0.004] and frequency of dupilumab use (OR: 3.306, 95% CI: 1.078-10.135; P = 0.036) were risk factors for adverse effects. The outcomes of ADRs were improved in 10 cases (15.38%) and completely recovered in 55 cases (84.62%).

Conclusion

Dupilumab has a good safety profile in Chinese children aged 6 months to 18 years for up to 2 years of treatment, with most adverse reactions being mild to moderate, and no serious ocular adverse reactions were reported. Age and frequency of dupilumab use were risk factors for adverse effects. Younger age and higher frequency of dupilumab use were associated with higher odds of ADRs.

Inhaling arsenic aggravates airway hyperreactivity by upregulating PNEC-sourced 5-HT in OVA-induced allergic asthma

Increasing epidemiological evidence has proved that early-life exposure to inorganic arsenic (As) elevates the risks of childhood asthma. The present research aimed to explore susceptibility of respiratory As exposure to allergic asthma in a mouse model. BALB/c mice on postnatal day (PND) 28 were exposed to ddH2O or NaAsO2 aerosol for 4 hours daily over 5 consecutive weeks via respiratory tract. Mice were sensitized by intraperitoneal injection of ovalbumin (OVA) combined with Alum Adjuvant on PND42 and PND56. Subsequently, mice were challenged with ddH2O or 1 %OVA through a nebulizer for 3 days starting from PND63. In As-exposed mice, OVA-sensitized goblet cell hyperplasia and airway mucosal secretion did not worsen. OVA-induced inflammatory cell infiltration and upregulation of Th2 cytokines, including IL-4, IL-5, and IL-13, were not aggravated in As-exposed mice. Interestingly, airway hyperreactivity was intensified in As-exposed asthmatic mice. Mechanistically, OVA-induced elevation of 5-hydroxytryptamine (5-HT), probably secreted by pulmonary neuroendocrine cells (PNECs), was exacerbated in As-exposed mice. OVA-induced upregulation of tryptophan hydroxylase (TPH)1 and TPH2, two 5-HT synthases, was aggravated in As-exposed mouse lungs. LX1032, a specific TPH inhibitor, suppressed As-induced elevation of pulmonary 5-HT content in asthmatic mice. Moreover, LX1032 alleviated As-evoked airway hyperreactivity in asthmatic mice. These results suggest that respiratory As exposure elevates airway hyperreactivity partially through upregulating PNEC-sourced 5-HT in OVA-induced allergic asthma, which provides significant insight about the hazards of environmental As exposure.

Preventing NLRP3 inflammasome activation: Therapeutic atrategy and challenges in atopic dermatitis

Atopic dermatitis (AD) is a prevalent inflammatory skin disorder characterized by its chronic, persistent, and recurrent nature. The pathophysiology of this condition is complex, involving various factors including cell-mediated immune responses, compromised skin barrier function, and alterations in hypersensitivity reactions. These components synergistically contribute to the perpetuation of the bothersome "itch-scratch-itch" cycle. Recent research has highlighted the significant role of the NLRP3 inflammasome in the development of AD and other inflammatory conditions. Current research indicates that the NLRP3 inflammasome plays a pivotal role in both the acute and chronic phases of AD by modulating the Th2/Th1 immune deviation. Moreover, the pharmacological suppression of NLRP3 has shown promising results in mitigating the pathological aspects of AD. This review outlines potential drug development strategies that target the NLRP3 inflammasome as a therapeutic approach for AD and the challenges faced in this endeavor.

Association between cytokines and progression-free survival in ovarian cancer following CRS/HIPEC treatment

BACKGROUND

The benefit of cytoreduction with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) for epithelial ovarian cancer (EOC) remains uncertain. This study investigated the relationship between serum cytokines, particularly monocyte chemoattractant protein-1 (MCP-1), a key inflammatory mediator, and recurrence risk in EOC patients undergoing CRS/HIPEC.

METHODS

From January 2018 to January 2023, serum cytokine levels were analyzed in 34 EOC patients (17 primary, 17 recurrent) before and after CRS/HIPEC using MILLIPLEX Magnetic Bead Panels. Cox proportional hazards regression calculated adjusted hazard ratios (HRs) after controlling for clinical variables. Immunohistochemical (IHC) staining was performed on tissue microarrays from 19 patients.

RESULTS

Higher 1-unit increment of MCP-1_Baseline were associated with increased recurrence risk within the first year post-CRS/HIPEC (HR: 1.010, 95% CI: 1.000-1.021). After one year, higher 1-unit increments of MCP-1_Post and MCP-1_Change were associated with increased recurrence risk. Lower IL-13 change and higher GROα change were associated with better progression-free survival (PFS) (p = 0.002 and p = 0.025, respectively). IHC analysis showed a trend towards worse PFS within the first year for patients with MCP-1 expression in tumor tissue (HR: 3.252, p = 0.264).

CONCLUSION

Cytokines, particularly MCP-1, may help predict PFS following CRS/HIPEC in EOC patients and could inform postoperative treatment decisions. Further research is needed to confirm these findings and explore clinical applications.

Healing action of Interleukin-4 (IL-4) in acute and chronic inflammatory conditions: Mechanisms and therapeutic strategies

Interleukin-4 (IL-4), which is traditionally associated with inflammation, has emerged as a key player in tissue regeneration. Produced primarily by T-helper 2 (Th2) and other immune cells, IL-4 activates endogenous lymphocytes and promotes M2 macrophage polarization, both of which are crucial for tissue repair. Moreover, IL-4 stimulates the proliferation and differentiation of various cell types, contributing to efficient tissue regeneration, and shows promise for promoting tissue regeneration after injury. This review explores the multifaceted roles of IL-4 in tissue repair, summarizing its mechanisms and potential for clinical application. This review delves into the multifaceted functions of IL-4, including its immunomodulatory effects, its involvement in tissue regeneration, and its potential therapeutic applications. We discuss the mechanisms underlying IL-4-induced M2 macrophage polarization, a crucial process for tissue repair. Additionally, we explore innovative strategies for delivering IL-4, including gene therapy, protein-based therapies, and cell-based therapies. By leveraging the regenerative properties of IL-4, we can potentially develop novel therapies for various diseases, including chronic inflammatory disorders, autoimmune diseases, and organ injuries. While early research has shown promise for the application of IL-4 in regenerative medicine, further studies are needed to fully elucidate its therapeutic potential and optimize its use.

Malignant behaviors and immune response in melanoma: Epstein-Barr virus induced gene 3 as a therapeutic target based on an in-vitro exploration

Background

Epstein-Barr virus induced gene 3 (EBI3), a member of the IL-12 family, is known to be involved in malignant progression in a variety of cancers, but its role in melanoma is unclear. The aim of this study was to explore the effects of EBI3 on the malignant phenotype melanoma to reveal its potential as a therapeutic target.

Methods

In this study, we used bioinformatics to analyze the expression of EBI3 in pan-cancer and verified its expression level in melanoma cells by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Subsequently, the effects of EBI3 knockdown on cell proliferation, migration and invasion were detected using the Cell Counting Kit-8 (CCK-8) and Transwell assays. Changes in immune-related cytokines were detected by ELISA, and macrophage polarization was observed using immunofluorescence. Finally, the phosphorylation levels of signaling pathways such as Smad3, STAT6 and cGAS-STING were analyzed by Western blot.

Results

EBI3 was evidently highly-expressed in melanoma, and silencing of EBI3 could visibly suppress the survival and migration/invasion of melanoma cells, concurrent with the increased levels of BAX and CDH1 and the decreased expressions of BCL2 and CDH2. Meanwhile, EBI3 knockdown diminished the phosphorylation levels of both Smad3 and STAT6 and the levels of immune response-relevant cytokines in melanoma cells, while aggravating the macrophage M1 polarization and the expression of cGAS, p-STING and p-IRE1 α in THP-1 monocyte-derived macrophages co-cultured with EBI3-silenced melanoma cells.

Conclusion

This study filled the blank on the involvement of EBI3 in melanoma, hinting the possibility of controlling EBI3 as a therapeutic strategy in the management of melanoma.

SOX13 as a potential prognostic biomarker linked to immune infiltration and ferroptosis inhibits the proliferation, migration, and metastasis of thyroid cancer cells

Background

SOX13 is a transcription factor belonging to the SOX family. SOX proteins are critical regulators of multiple cancer progression, and some are known to control carcinogenesis. Nevertheless, the functional and clinical significance of SOX13 in human thyroid cancer (THCA) remain largely unelucidated.

Methods

Data on SOX13 expression were obtained through The Cancer Genome Atlas together with Gene Expression Omnibus. Co-expression, differential expression, and functional analyses of genes were investigated by databases. Associations between SOX13 levels, immune infiltration, ferroptosis, and immune checkpoint gene levels were analyzed. Genetic changes in SOX13 were investigated using CBioPortal. Associations between SOX13 levels and THCA clinicopathological features were analyzed and nomogram modeling for diagnostic and prognostic prediction. The influence of SOX13 on proliferation, migration, and metastasis was determined in KTC-1 and TPC-1 cell lines.

Results

SOX13 was significantly lower in THCA tumors compared to controls. In addition, upregulated SOX13 gene mutation were evident in thyroid cancer. SOX13-associated genes exhibited differential expression in pathways associated with thyroid cancer development. Significant associations were found between SOX13 levels, immune infiltration, ferroptosis, and immune checkpoint genes in THCA tissue. SOX13 levels correlated with THCA stage, histologic grade, and primary neoplasm focus types, and independently predicted overall and progression-free intervals. SOX13 expression effectively distinguished between tumor and normal thyroid tissue. Spearman correlations highlighted a significant relationship between SOX13 and ferroptosis-associated genes. Overexpression of SOX13 enhances the inhibition of RSL3 (iron death activator) on the cell viability of TPC-1. Higher SOX13 levels in Thyroid cancer cells may lead to reduced proliferation, migration, and metastasis by regulating ferroptosis.

Conclusion

Reduced SOX13 expression inversely impacts patient prognosis. In addition, SOX13 strongly regulates cancer immunity and Ferroptosis. Hence, SOX13 has great promise as a bioindicator for both thyroid cancer prognosis and immune cell invasion.

The IL-33/ST2 signaling axis drives pathogenesis in acute SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), remains a significant threat to global public health. Immunopathological damage plays a role in driving pneumonia, acute respiratory distress syndrome (ARDS), and multiorgan failure in severe COVID-19. Therefore, dissecting the pulmonary immune response to SARS-CoV-2 infection is critical to understand disease pathogenesis and identify immune pathways targetable by therapeutic intervention. Considering that the type 2 cytokine IL-13 enhances COVID-19 disease severity, therapeutic targeting of upstream signals that drive type 2 immunity may confer further protection. In this study, we investigate the role of the IL-33/ST2 signaling axis, a potent inducer of type 2 immunity in the lung, in a mouse model of COVID-19. Upon infection with mouse-adapted SARS-CoV-2 MA10, ST2 -/- mice had significantly improved weight loss and survival (69.2% vs 13.3% survival; P = 0.0005), as compared to wild-type mice. In a complementary pharmacologic approach, IL-33/ST2 signaling was inhibited using HpBARI_Hom2, a helminth derived protein that binds to mouse ST2 and blocks IL-33 signaling. In SARS-CoV-2 MA10 infection, HpBARI_Hom2-treated mice had significantly improved weight loss and survival (60% vs 10% survival; P = 0.0035), as compared to inert control-treated mice. These data demonstrate that loss of IL-33/ST2 signaling confers protection during acute SARS-CoV-2 MA10 infection, implicating the IL-33/ST2 signaling axis as an enhancer of COVID-19 disease severity. The protection conferred by pharmacologic blockade of IL-33/ST2 signaling was independent of viral control, as HpBARI_Hom2-treated mice had no reduction in viral titers. This finding suggests an immunopathogenic role for IL-33/ST2 signaling. One potential mechanism through which IL-33/ST2 signaling may drive severe disease is through enhancement of type 2 immune pathways including IL-5 production, as pulmonary IL-5 concentrations were found to depend on IL-33/ST2 signaling in acute SARS-CoV-2 MA10 infection.

SKAP1 Expression in Cancer Cells Enhances Colon Tumor Growth and Impairs Cytotoxic Immunity by Promoting Neutrophil Extracellular Trap Formation via the NFATc1/CXCL8 Axis

The mechanisms underlying the development and progression of colon cancer are not fully understood. Herein, Src kinase associated phosphoprotein 1 (SKAP1), an immune cell adaptor, is identified as a novel colon cancer-related gene. SKAP1 expression is significantly increased in colon cancer cells. High SKAP1 levels are independently predictive of poor survival in patients with colon cancer. Notably, SKAP1 expression in colon cancer cells exerted a significant tumor-promoting effect in vivo rather than in vitro. Screening of tumor-infiltrating immune cells revealed the involvement of neutrophils in SKAP1-induced colon tumor promotion. Enhanced formation of neutrophil extracellular traps (NETs) is found to be a key downstream event that contributed to the pro-tumor role of SKAP1. In colon cancer cells, SKAP1 increased the expression of C-X-C motif chemokine ligand 8 (CXCL8) via nuclear factor of activated T cells c1 (NFATc1). The blockade of CXCL8 or NFATc1 largely attenuated neutrophil infiltration, NET formation, and tumor promotion induced by SKAP1. Furthermore, inhibiting SKAP1-induced NET significantly enhanced the antitumor efficiency of adoptive natural killer cell therapy in colon tumor models. In conclusion, SKAP1 significantly promotes colon cancer growth via the cancer cell/neutrophil NFATc1/CXCL8/NET axis, suggesting that SKAP1 is a potential target for colon cancer therapy.

Therapeutic monoclonal antibodies in allergy: Targeting IgE, cytokine, and alarmin pathways

The etiology of allergy is closely linked to type 2 inflammatory responses ultimately leading to the production of allergen-specific immunoglobulin E (IgE), a key driver of many allergic conditions. At a high level, initial allergen exposure disrupts epithelial integrity, triggering local inflammation via alarmins including IL-25, IL-33, and TSLP, which activate type 2 innate lymphoid cells as well as other immune cells to secrete type 2 cytokines IL-4, IL-5 and IL-13, promoting Th2 cell development and eosinophil recruitment. Th2 cell dependent B cell activation promotes the production of allergen-specific IgE, which stably binds to basophils and mast cells. Rapid degranulation of these cells upon allergen re-exposure leads to allergic symptoms. Recent advances in our understanding of the molecular and cellular mechanisms underlying allergic pathophysiology have significantly shaped the development of therapeutic intervention strategies. In this review, we highlight key therapeutic targets within the allergic cascade with a particular focus on past, current and future treatment approaches using monoclonal antibodies. Specific targeting of alarmins, type 2 cytokines and IgE has shown varying degrees of clinical benefit in different allergic indications including asthma, chronic spontaneous urticaria, atopic dermatitis, chronic rhinosinusitis with nasal polyps, food allergies and eosinophilic esophagitis. While multiple therapeutic antibodies have been approved for clinical use, scientists are still working on ways to improve on current treatment approaches. Here, we provide context to understand therapeutic targeting strategies and their limitations, discussing both knowledge gaps and promising future directions to enhancing clinical efficacy in allergic disease management.

Arecoline promotes fibroblast activation and M2-macrophage polarization by up-regulating the expression of IL-4

OBJECTIVE

To determine the biological effects of arecoline on oral submucous fibrosis (OSF).

DESIGN

The differential genes between OSF tissue and normal oral tissue were collected form GSE64216 dataset, analyzed by Gene Expression Omnibus (GEO) database. Real-time PCR and immunohistochemistry were used to analyze the expression of IL-4 gene and protein in oral tissue. Enzyme-linked immunosorbent assay (ELISA) was used to analyze the expression of exocrine IL-4 protein in human oral fibroblasts (HOF) pre-treated by arecoline. Cell Counting Kit-8 (CCK-8) and transwell assays were used to analyze the proliferation and migration of HOF cells, respectively. After IL-4 was knocked down by short hairpin (sh) plasmid, the proliferation and migration of HOF cells were detected. Flow cytometry was used to analyze the proportion of M2-macrophages. Real-time PCR and immunohistochemistry were used to verify the expression of biomarker proteins of macrophages in OSF tissues.

RESULTS

The expression of IL-4 gene and protein were both up-regulated in OSF tissue. Arecoline could enhance the expression of IL-4 gene and exocrine protein in HOF cells, and promote the proliferation and migration of HOF cells. While knockdown of IL-4 could inhibit arecoline-induced proliferation and migration in HOF cells. The results of flow cytometry showed that recombinant human IL-4 (rhIL-4) protein could increase the proportion of M2-macrophages. Similarly, the results of real-time PCR and immunohistochemistry showed the expression of ARG1 (Biomarker proteins of M2-macrophage) was up-regulated in OSF tissues.

CONCLUSION

Arecoline promotes activation of fibroblasts and polarization of M2-macrophages by up-regulating the expression of IL-4.

Mixed Th1/Th2/Th17 Responses Induced by Plant Oil Adjuvant-Based B. bronchiseptica Vaccine in Mice, with Mechanisms Unraveled by RNA-Seq, 16S rRNA and Metabolomics

BACKGROUND/OBJECTIVES

The current Bordetella bronchiseptica (Bb) vaccine, when adjuvanted with alum, does not elicit adequate robust cellular immunity or effective antibody defense against Bb attacks. Unfortunately, antibiotic treatment generally represents an ineffective strategy due to the development of resistance against a broad range of antibiotics.

METHODS

The present study was designed to investigate the immune response, protective capabilities and underlying mechanisms of a plant oil-based adjuvant E515 formulated with inactivated Bb antigen as a potential vaccine candidate against Bordetella bronchiseptica.

RESULTS

Immunization studies revealed that a combination of SO, VE and GS (E515) exhibited a good synergistic adjuvant effect. The E515 adjuvanted Bb vaccine was proven to be highly efficacious and induced a mixed Th1/Th2/Th17 immune response in mice, leading to a significant increase in Bb-specific IgG, IgG1 and IgG2a antibodies, proliferative lymphocyte responses and cytokine levels (by lymphocytes and serum) and effectively induced responses by CD4+ TE, TM cells and B cells. The E515 adjuvant significantly enhanced the immune protection provided by the Bb vaccine in a mice model, as indicated by a reduced bacterial burden in the lungs. Multi-omics sequencing analysis revealed that E515 functions as an adjuvant by modulating critical pathways, including cytokine-cytokine receptor interaction, the IL-17 signaling pathway and the chemokine signaling pathway. This modulation also included interactions with beneficial species of bacteria including Alistipes, Odoribacter and Colidextribacter, as well as energy and lipid-related metabolites, thus highlighting its role as an immunomodulatory agent.

CONCLUSION

Collectively, our results demonstrate the huge potential of E515-Bb vaccine candidates, thus highlighting the vegetable oil original adjuvant E515 as a promising agent for the development of new veterinary vaccines.

Formation and biological activities of foreign body giant cells in response to biomaterials

The integration of biomaterials in medical applications triggers the foreign body response (FBR), a multi-stage immune reaction characterized by the formation of foreign body giant cells (FBGCs). Originating from the fusion of monocyte/macrophage lineage cells, FBGCs are pivotal participants during tissue-material interactions. This review provides an in-depth examination of the molecular processes during FBGC formation, highlighting signaling pathways and fusion mediators in response to both exogenous and endogenous stimuli. Moreover, a wide range of material-specific characteristics, such as surface chemical and physical properties, has been proven to influence the fusion of macrophages into FBGCs. Multifaceted biological activities of FBGCs are also explored, with emphasis on their phagocytic capabilities and extracellular secretory functions, which profoundly affect the vascularization, degradation, and encapsulation of the biomaterials. This review further elucidates the heterogeneity of FBGCs and their diverse roles during FBR, as demonstrated by their distinct behaviors in response to different materials. By presenting a comprehensive understanding of FBGCs, this review intends to provide strategies and insights into optimizing biocompatibility and the therapeutic potential of biomaterials for enhanced stability and efficacy in clinical applications. STATEMENT OF SIGNIFICANCE: As a hallmark of the foreign body response (FBR), foreign body giant cells (FBGCs) significantly impact the success of implantable biomaterials, potentially leading to complications such as chronic inflammation, fibrosis, and device failure. Understanding the role of FBGCs and modulating their responses are vital for successful material applications. This review provides a comprehensive overview of the molecules and signaling pathways guiding macrophage fusion into FBGCs. By elucidating the physical and chemical properties of materials inducing distinct levels of FBGCs, potential strategies of materials in modulating FBGC formation are investigated. Additionally, the biological activities of FBGCs and their heterogeneity in responses to different material categories in vivo are highlighted in this review, offering crucial insights for improving the biocompatibility and efficacy of biomaterials.

Expression profile of Toll-like receptors and cytokines in the cecal tonsil of chickens challenged with Eimeria tenella

Chicken coccidiosis, caused by Eimeria spp., seriously affects the development of the poultry breeding industry. Currently, extensive studies of chicken coccidiosis are mostly focused on acquired immune responses, while information about the innate immune response of chicken coccidiosis is lacking. Toll-like receptor (TLR), the key molecule of the innate immune response, connects innate and adaptive immune responses and induces an immune response against various pathogen infections. Therefore, the quantitative real-time PCR was used to characterize the expression profile of chicken TLRs (chTLRs) and associated cytokines in the cecal tonsil of chickens infected with Eimeria tenella. The results showed that the expression of chTLR1a, chTLR2a, and chTLR5 was significantly upregulated at 3 h post-infection, while chTLR1b, chTLR2b, chTLR3, chTLR7, chTLR15 and chTLR21 was significantly downregulated (p < 0.05). In addition, chTLR1a expression rapidly reached the peaked expression at 3 h post-infection, while chTLR2b and chTLR15 peaked at 168 h post-infection, and chTLR2a expression was highest among chTLRs, peaking at 48 h post-infection (p < 0.05). For cytokines, interleukin (IL)-6 and tumor necrosis factor (TNF)-α peaked at 96 h post-infection, IL-4 and IL-12 peaked at 144 h post-infection, and interferon-γ expression was highest among cytokines at 120 h post-infection. In addition, IL-12 and IL-17 were markedly upregulated at 6 h post-infection (p < 0.05). These results provide insight into innate immune molecules during E. tenella infection in chickens and suggest that innate immune responses may mediate resistance to chicken coccidiosis.

Daphnetin alleviates allergic airway inflammation by inhibiting T-cell activation and subsequent JAK/STAT6 signaling

Allergic asthma is a major health burden on society as a chronic respiratory disease characterized by inflammation and muscle tightening around the airways in response to inhaled allergens. Daphne kiusiana Miquel is a medicinal plant that can suppress allergic airway inflammation; however, its specific molecular mechanisms of action are unclear. In this study, we aimed to elucidate the mechanisms by which D. kiusiana inhibits allergic airway inflammation. We evaluated the anti-inflammatory effects of the ethyl acetate (EA) fraction of D. kiusiana and its major compound, daphnetin, on murine T lymphocyte EL4 cells stimulated with phorbol 12-myristate 13-acetate and ionomycin in vitro and on asthmatic mice stimulated with ovalbumin in vivo. The EA fraction and daphnetin inhibited T-helper type 2 (Th2) cytokine secretion, serum immunoglobulin E production, mucus secretion, and inflammatory cell recruitment in vivo. In vitro, daphnetin suppressed intracellular Ca2+ mobilization (a critical regulator of nuclear factor of activated T cells) and functions of the activator protein 1 transcription factor to reduce interleukin (IL)-4 and IL-13 expression. Daphnetin effectively suppressed the IL-4/-13-induced activation of Janus kinase (JAK)/signal transducer and activator of transcription 6 (STAT6) signaling in vitro and in vivo, thereby inhibiting the expression of GATA3 and PDEF, two STAT6-target genes responsible for producing Th2 cytokines and mucins. These findings indicate that daphnetin suppresses allergic airway inflammation by stabilizing intracellular Ca2+ levels and subsequently inactivating the JAK/STAT6/GATA3/PDEF pathway, suggesting that daphnetin is a promising alternative to existing asthma treatments.

Whence and wherefore IgE?

Despite the near ubiquitous presence of Ig-based antibodies in vertebrates, IgE is unique to mammals. How and why it emerged remains mysterious. IgE expression is greatly constrained compared to other IgH isotypes. While other IgH isotypes are relatively abundant, soluble IgE has a truncated half-life, and IgE plasma cells are mostly short-lived. Despite its rarity, IgE is consequential and can trigger life-threatening anaphylaxis. IgE production reflects a dynamic steady state with IgG memory B cells feeding short-lived IgE production. Emerging evidence suggests that IgE may also potentially be produced in longer-lived plasma cells as well, perhaps as an aberrancy stemming from its evolutionary roots from an antibody isotype that likely functioned more like IgG. As a late derivative of an ancient systemic antibody system, the benefits of IgE in mammals likely stems from the antibody system's adaptive recognition and response capability. However, the tendency for massive, systemic, and long-lived production, common to IgH isotypes like IgG, were likely not a good fit for IgE. The evolutionary derivation of IgE from an antibody system that for millions of years was good at antigen de-sensitization to now functioning as a highly specialized antigen-sensitization function required heavy restrictions on antibody production-insufficiency of which may contribute to allergic disease.

Harnessing cytokines to optimize chimeric antigen receptor-T cell therapy for gastric cancer: Current advances and innovative strategies

Enormous patients with gastric cancer (GC) are insensitive to chemotherapy and targeted therapy without the chance of radical surgery, so immunotherapy may supply a novel choice for them. Chimeric antigen receptor (CAR)-T cell therapy has the advantages of higher specificity, stronger lethality, and longer-lasting efficacy, and it has the potential for GC in the future. However, its application still faces numerous obstacles in terms of accuracy, efficacy, and safety. Cytokines can mediate the migration, proliferation, and survival of immune cells, regulate the duration and strength of immune responses, and are involved in the occurrence of severe side effects in CAR-T cell therapy. The expression levels of specific cytokines are associated with the genesis, invasion, metastasis, and prognosis of GC. Applications of cytokines and their receptors in CAR-T cell therapy have emerged, and various cytokines and their receptors have contributed to improving CAR-T cell anti-tumor capabilities. Large amounts of central cytokines in this therapy include chemokines, interleukins (ILs), transforming growth factor-β (TGF-β), and colony-stimulating factors (CSFs). Meanwhile, researchers have explored the combination therapy in treating GC, and several approaches applied to other malignancies can also be considered as references. Therefore, our review comprehensively outlines the biological functions and clinical significance of cytokines and summarizes current advances and innovative strategies for harnessing cytokines to optimize CAR-T cell therapy for GC.

Stimuli-Mediated Macrophage Switching, Unraveling the Dynamics at the Nanoplatforms-Macrophage Interface

Macrophages play an essential role in immunotherapy and tissue regeneration owing to their remarkable plasticity and diverse functions. Recent bioengineering developments have focused on using external physical stimuli such as electric and magnetic fields, temperature, and compressive stress, among others, on micro/nanostructures to induce macrophage polarization, thereby increasing their therapeutic potential. However, it is difficult to find a concise review of the interaction between physical stimuli, advanced micro/nanostructures, and macrophage polarization. This review examines the present research on physical stimuli-induced macrophage polarization on micro/nanoplatforms, emphasizing the synergistic role of fabricated structure and stimulation for advanced immunotherapy and tissue regeneration. A concise overview of the research advancements investigating the impact of physical stimuli, including electric fields, magnetic fields, compressive forces, fluid shear stress, photothermal stimuli, and multiple stimulations on the polarization of macrophages within complex engineered structures, is provided. The prospective implications of these strategies in regenerative medicine and immunotherapeutic approaches are highlighted. This review will aid in creating stimuli-responsive platforms for immunomodulation and tissue regeneration.

Balancing the Scales: The Dual Role of Interleukins in Bone Metastatic Microenvironments

Bone metastases, a common and debilitating consequence of advanced cancers, involve a complex interplay between malignant cells and the bone microenvironment. Central to this interaction are interleukins (ILs), a group of cytokines with critical roles in immune modulation and inflammation. This review explores the dualistic nature of pro-inflammatory and anti-inflammatory interleukins in bone metastases, emphasizing their molecular mechanisms, pathological impacts, and therapeutic potential. Pro-inflammatory interleukins, such as IL-1, IL-6, and IL-8, have been identified as key drivers in promoting osteoclastogenesis, tumor proliferation, and angiogenesis. These cytokines create a favorable environment for cancer cell survival and bone degradation, contributing to the progression of metastatic lesions. Conversely, anti-inflammatory interleukins, including IL-4, IL-10, and IL-13, exhibit protective roles by modulating immune responses and inhibiting osteoclast activity. Understanding these opposing effects is crucial for developing targeted therapies aimed at disrupting the pathological processes in bone metastases. Key signaling pathways, including NF-κB, JAK/STAT, and MAPK, mediate the actions of these interleukins, influencing tumor cell survival, immune cell recruitment, and bone remodeling. Targeting these pathways presents promising therapeutic avenues. Current treatment strategies, such as the use of denosumab, tocilizumab, and emerging agents like bimekizumab and ANV419, highlight the potential of interleukin-targeted therapies in mitigating bone metastases. However, challenges such as therapeutic resistance, side effects, and long-term efficacy remain significant hurdles. This review also addresses the potential of interleukins as diagnostic and prognostic biomarkers, offering insights into patient stratification and personalized treatment approaches. Interleukins have multifaceted roles that depend on the context, including the environment, cell types, and cellular interactions. Despite substantial progress, gaps in research persist, particularly regarding the precise mechanisms by which interleukins influence the bone metastatic niche and their broader clinical implications. While not exhaustive, this overview underscores the critical roles of interleukins in bone metastases and highlights the need for continued research to fully elucidate their complex interactions and therapeutic potential. Addressing these gaps will be essential for advancing our understanding and treatment of bone metastases in cancer patients.

Steady-state, therapeutic, and helminth-induced IL-4 compromise protective CD8 T cell bystander activation

Memory CD8 T cells (Tmem) can be activated into innate-like killers by cytokines like IL-12, IL-15, and/or IL-18; but mechanisms regulating this phenomenon (termed bystander activation) are not fully resolved. We found strain-intrinsic deficiencies in bystander activation using specific pathogen-free mice, whereby basal IL-4 signals antagonize IL-18 sensing. We show that therapeutic and helminth-induced IL-4 impairs protective bystander-mediated responses against pathogens. However, this IL-4/IL-18 axis does not completely abolish bystander activation but rather tunes the expression of direct versus indirect mediators of cytotoxicity (granzymes and interferon-γ, respectively). We show that antigen-experience overrides strain-specific deficiencies in bystander activation, leading to uniform IL-18 receptor expression and enhanced capacity for bystander activation/cytotoxicity. Our data highlight that bystander activation is not a binary process but tuned/deregulated by other cytokines that are elevated by contemporaneous infections. Further, our findings underscore the importance of antigen-experienced Tmem to dissect the contributions of bystander Tmem in health and disease.

A multifunctional antibody fusion protein 57103 targeting CD24, IL-4R, and αvβ3 for treating cancer and regulating the tumor microenvironment

Cancer is one of the top 10 fatal diseases worldwide, among which advanced metastatic carcinoma has the highest mortality rate. Sunitinib and immune checkpoint blockers are commonly used to treat metastatic renal carcinoma with limited efficacy. Therefore, there is an urgent need to develop novel targeted therapies for metastatic renal cancer. In this study, we designed an antibody fusion protein, 57103, that simultaneously targeted the cluster of differentiation 24 (CD24), interleukin 4 receptor (IL-4R), and integrin receptors αvβ3 and α5β1. In vitro assays showed that 57103 significantly suppressed the proliferation, migration, invasion, colony formation, and adhesion abilities of renal cancer cells, resulting in a comprehensive and significant antitumor effect. Furthermore, 57103 inhibited angiogenesis, promoted THP1-derived M0-type macrophage phagocytosis, and enhanced the antibody-dependent cellular cytotoxicity of peripheral blood mononuclear and NK92MI-CD16a cells. In vivo experiments revealed significant inhibition of tumor growth in ACHN cell xenograft nude mice and an MC38-hCD24 tumor-bearing mouse model. Immunohistochemical analysis showed that 57103 decreased the proliferation and induced the apoptosis of renal cancer cells, while inhibiting angiogenesis. The MC38-hPDL1 and MC38-hCD24-hPDL1 tumor-bearing mouse models further offer the possibility of combining 57103 with the PDL1 antagonist atezolizumab. In conclusion, 57103 is a potential candidate drug for the treatment of metastatic renal carcinoma or PDL1-overexpressing cancer.

Regression of metastatic malignant melanoma with dupilumab: A case report

Excoriated pruritus can be an intolerable symptom in patients with cancer where Type 2 inflammation and its associated cytokines IL-4 and IL-13 play major roles in the pruritus. Dupilumab, an antibody blocking IL-4 and IL-13, is approved for treating moderate to severe atopic dermatitis (AD) where itching is a significant symptom. We present a case report of intractable malignancy-associated AD and pruritus with eosinophilia in a patient with stage IV malignant melanoma who was treated with dupilumab. Biweekly treatment with dupilumab led to an immediate improvement in itching and resolution of the AD, which subsided after a few doses and without significant adverse effects. Routine radiologic monitoring of the malignant melanoma showed concomitant resolution of secondary nodules in the lung, liver, and pleura. It was concluded that dupilumab may be a safe and effective treatment for intractable malignancy-associated AD with pruritus and may have potential for moderating metastatic malignant melanoma.

Dupilumab for atopic dermatitis in metastatic cancer

We present a case of a 47-year-old male with severe atopic dermatitis and metastatic renal cell carcinoma managed successfully with dupilumab. This case further supports the safety of dupilumab in patients with active malignancy, an area currently with limited data.

Intestinal microflora promotes Th2-mediated immunity through NLRP3 in damp and heat environments

Background

With the worsening of the greenhouse effect, the correlation between the damp-heat environment (DH) and the incidence of various diseases has gained increasing attention. Previous studies have demonstrated that DH can lead to intestinal disorders, enteritis, and an up-regulation of NOD-like receptor protein 3 (NLRP3). However, the mechanism of NLRP3 in this process remains unclear.

Methods

We established a DH animal model to observe the impact of a high temperature and humidity environment on the mice. We sequenced the 16S rRNA of mouse feces, and the RNA transcriptome of intestinal tissue, as well as the levels of cytokines including interferon (IFN)-γ and interleukin (IL)-4 in serum.

Results

Our results indicate that the intestinal macrophage infiltration and the expression of inflammatory genes were increased in mice challenged with DH for 14 days, while the M2 macrophages were decreased in Nlrp3 -/- mice. The alpha diversity of intestinal bacteria in Nlrp3 -/- mice was significantly higher than that in control mice, including an up-regulation of the Firmicutes/Bacteroidetes ratio. Transcriptomic analysis revealed 307 differentially expressed genes were decreased in Nlrp3 -/- mice compared with control mice, which was related to humoral immune response, complement activation, phagocytic recognition, malaria and inflammatory bowel disease. The ratio of IFN-γ/IL-4 was decreased in control mice but increased in Nlrp3 -/- mice.

Conclusions

Our study found that the inflammation induced by DH promotes Th2-mediated immunity via NLRP3, which is closely related to the disruption of intestinal flora.

Lessons on protein structure from interleukin-4: All disulfides are not created equal

Interleukin-4 (IL-4) is a hematopoietic cytokine composed by a four-helix bundle stabilized by an antiparallel beta-sheet and three disulfide bonds: Cys3-Cys127, Cys24-Cys65, and Cys46-Cys99. IL-4 is involved in several immune responses associated to infection, allergy, autoimmunity, and cancer. Besides its physiological relevance, IL-4 is often used as a "model" for protein design and engineering. Hence, to understand the role of each disulfide in the structure and dynamics of IL-4, we carried out several spectroscopic analyses (circular dichroism [CD], fluorescence, nuclear magnetic resonance [NMR]), and molecular dynamics (MD) simulations on wild-type IL-4 and four IL-4 disulfide mutants. All disulfide mutants showed loss of structure, altered interhelical angles, and looser core packings, showing that all disulfides are relevant for maintaining the overall fold and stability of the four-helix bundle motif, even at very low pH. In the absence of the disulfide connecting both protein termini Cys3-Cys127, C3T-IL4 showed a less packed protein core, loss of secondary structure (~9%) and fast motions on the sub-nanosecond time scale (lower S2 order parameters and larger τc correlation time), especially at the two protein termini, loops, beginning of helix A and end of helix D. In the absence of Cys24-Cys65, C24T-IL4 presented shorter alpha-helices (14% loss in helical content), altered interhelical angles, less propensity to form the small anti-parallel beta-sheet and increased dynamics. Simultaneously deprived of two disulfides (Cys3-Cys127 and Cys24-Cys65), IL-4 formed a partially folded "molten globule" with high 8-anilino-1-naphtalenesulphonic acid-binding affinity and considerable loss of secondary structure (~50%decrease), as shown by the far UV-CD, NMR, and MD data.

Interleukin-4 Modulates Neuroinflammation by Inducing Phenotypic Transformation of Microglia Following Subarachnoid Hemorrhage

Neuroinflammation, a key pathological feature following subarachnoid hemorrhage (SAH), can be therapeutically targeted by inhibiting microglia M1 polarization and promoting phenotypic transformation to M2 microglia. Interleukin-4 (IL-4) is a pleiotropic cytokine known to its regulation of physiological functions of the central nervous system (CNS) and mediate neuroinflammatory processes. However, its specific role in neuroinflammation and microglia responses following SAH remains unexplored. In this investigation, we established both in vivo and in vitro SAH models and employed a comprehensive array of assessments, including ELISA, neurofunctional profiling, immunofluorescence staining, qRT-PCR, determination of phagocytic capacity, and RNA-Seq analyses. The findings demonstrate an elevated expression of IL-4 within cerebrospinal fluid (CSF) subsequent to SAH. Furthermore, exogenous administration of IL-4 ameliorates post-SAH neurofunctional deficits, attenuates cellular apoptosis, fosters M2 microglia phenotype conversion, and mitigates neuroinflammatory responses. The RNA-Seq analysis signifies that IL-4 governs the modulation of neuroinflammation in microglia within an in vitro SAH model through intricate cascades of signaling pathways, encompassing interactions between cytokines and cytokine receptors. These discoveries not only augment comprehension of the neuropathogenesis associated with post-SAH neuroinflammation but also present novel therapeutic targets for the management thereof.

Engineering Anticytokine Antibodies for Immune Modulation

The delicate balance of immune homeostasis is regulated by the interactions between cytokines and their cognate cell surface signaling receptors. There is intensive interest in harnessing cytokines as drugs for diseases such as cancer and autoimmune disorders. However, the multifarious and often contradictory activities of cytokines, coupled with their short serum half-lives, limit clinical performance and result in dangerous toxicities. There is thus growing emphasis on manipulating natural cytokines to enhance their selectivity, safety, and durability through various strategies. One strategy that has gained traction in recent years is the development of anticytokine Abs that not only extend the circulation half-life of cytokines but also specifically bias their immune activities through multilayered molecular mechanisms. Although Abs are notorious for their antagonistic activities, this review focuses on anticytokine Abs that selectively agonize the activity of the target protein. This approach has potential to help realize the clinical promise of cytokine-based therapies.

Functionally Relevant Cytokine/Receptor Axes in Myelofibrosis

Dysregulated inflammatory signaling is a key feature of myeloproliferative neoplasms (MPNs), most notably of myelofibrosis (MF). Indeed, MF is considered the prototype of onco-inflammatory hematologic cancers. While increased levels of circulatory and bone marrow cytokines are a well-established feature of all MPNs, a very recent body of literature is intriguingly pinpointing the selective overexpression of cytokine receptors by MF hematopoietic stem and progenitor cells (HSPCs), which, by contrast, are nearly absent or scarcely expressed in essential thrombocythemia (ET) or polycythemia vera (PV) cells. This new evidence suggests that MF CD34+ cells are uniquely capable of sensing inflammation, and that activation of specific cytokine signaling axes may contribute to the peculiar aggressive phenotype and biological behavior of this disorder. In this review, we will cover the main cytokine systems peculiarly activated in MF and how cytokine receptor targeting is shaping a novel therapeutic avenue in this disease.

Interleukin-13 (IL-13)-A Pleiotropic Cytokine Involved in Wound Healing and Fibrosis

The liver, as a central metabolic organ, is systemically linked to metabolic-inflammatory diseases. In the pathogenesis of the metabolic syndrome, inflammatory and metabolic interactions between the intestine, liver, and adipose tissue lead to the progression of hepatic steatosis to metabolic-dysfunction-associated steatohepatitis (MASH) and consecutive MASH-induced fibrosis. Clinical and animal studies revealed that IL-13 might be protective in the development of MASH through both the preservation of metabolic functions and Th2-polarized inflammation in the liver and the adipose tissue. In contrast, IL-13-associated loss of mucosal gut barrier function and IL-13-associated enhanced hepatic fibrosis may contribute to the progression of MASH. However, there are only a few publications on the effect of IL-13 on metabolic diseases and possible therapies to influence them. In this review article, different aspects of IL-13-associated effects on the liver and metabolic liver diseases, which are partly contradictory, are summarized and discussed on the basis of the recent literature.