A metalloproteinase disintegrin that releases tumour-necrosis factor-alpha from cells

Stimuli-Responsive Nanomedicines for the Treatment of Non-cancer Related Inflammatory Diseases

Nanomedicines offer a means to overcome the limitations associated with traditional drug dosage formulations by affording drug protection, enhanced drug bioavailability, and targeted drug delivery to affected sites. Inflamed tissues possess unique microenvironmental characteristics (including excessive reactive oxygen species, low pH levels, and hypoxia) that stimuli-responsive nanoparticles can employ as triggers to support on-demand delivery, enhanced accumulation, controlled release, and activation of anti-inflammatory drugs. Stimuli-responsive nanomedicines respond to physicochemical and pathological factors associated with diseased tissues to improve the specificity of drug delivery, overcome multidrug resistance, ensure accurate diagnosis and precision therapy, and control drug release to improve efficacy and safety. Current stimuli-responsive nanoparticles react to intracellular/microenvironmental stimuli such as pH, redox, hypoxia, or specific enzymes and exogenous stimuli such as temperature, magnetic fields, light, and ultrasound via bioresponsive moieties. This review summarizes the general strategies employed to produce stimuli-responsive nanoparticles tailored for inflammatory diseases and all recent advances, reports their applications in drug delivery, and illustrates the progress made toward clinical translation.

Research progress on ADAM28 in malignant tumors

A disintegrin and metalloproteinase (ADAM) 28 belongs to the zinc-dependent metalloproteinase superfamily and has a signal sequence at its N-terminus that can direct the protein into the secretory pathway. ADAM28 is a multifunctional protein that has been shown to play a role in regulating numerous biological processes, including cell adhesion, cell fusion, membrane protein shedding, protein hydrolysis, and signaling pathway modulation. ADAM28 is highly expressed in numerous malignant tumors and plays a pivotal role in the proliferation, metastasis and drug resistance of these tumors by acting on substrates such as IGFBP-3, vWF and CTGF, thereby promoting PSGL-1/P-selectin-mediated cell adhesion. Consequently, inhibiting ADAM28 could impede tumor proliferation, metastasis and drug resistance, which suggests that ADAM28 may serve as a prognostic indicator of and potential therapeutic target for malignant tumors. In this article, the structure and function of ADAM28 and its correlation with the onset and progression of human malignant tumors are primarily examined. Additionally, the potential applications of ADAM28 in tumor research are investigated to offer a theoretical foundation and reference for the clinical diagnosis and treatment of malignant tumors.

Mucin 4 expression is associated with metastasis in triple-negative breast cancer and can be tackled by soluble TNF blockade, improving immunotherapy outcome

PURPOSE

Triple-negative breast cancer (TNBC) has the worst prognosis among breast cancers. Immunotherapy is a therapeutic option, but there is no biomarker to guide promising combination treatments. Mucin 4 (MUC4) favors metastasis in preclinical cancer models. This study evaluates the efficacy of soluble TNF (sTNF) neutralization to tackle MUC4 expression preventing metastasis in combination with immunotherapy, and the potential use of MUC4 as a prognostic and predictive biomarker in TNBC patients.

EXPERIMENTAL DESIGN

To explore TNF modulation of MUC4 expression, a panel of TNBC cell lines was used. To assess the effect of sTNF blockade with a dominant negative molecule in combination with anti-PD-1 antibody on lung metastasis and overall survival (OS), 4T1 and LMM3 tumors were used. MUC4, PD-L1 and Ki-67 expression was evaluated by immunohistochemistry, and tumor infiltrating lymphocytes (TILs) were assessed by H&E staining, in a cohort of 49 early TNBC patients treated with chemotherapy.

RESULTS

TNF neutralization reduces MUC4 expression in TNBC cell lines. Only the combination of sTNF blockade with anti-PD-1 antibody prevents metastasis and increases mice survival. In early TNBC patients MUC4 expression is inversely associated with TILs presence and PD-L1 and Ki-67 expression. Finally, MUC4 is associated with metastasis and is an independent biomarker of poor OS.

CONCLUSIONS

We proved the existence of a sTNF/MUC4 axis in TNBC that can be actionable by sTNF neutralization, preventing metastasis. We suggest that MUC4 is a suitable biomarker to guide immunotherapy in TNBC, together with the administration of sTNF blocking drugs to improve outcome.

Bacterial-induced Duox-ROS regulates the Imd immune pathway in the gut by modulating the peritrophic matrix

The Duox-reactive oxygen species (ROS) system and the immune deficiency (Imd) pathway play a major role in insect gut immunity. However, their interaction to accomplish an effective immune response is still unclear. Here, we show that Duox regulates the peritrophic matrix (PM) and further affects the Imd immune response to pathogens in Bactrocera dorsalis. This regulation requires a nuanced ROS balance: low H2O2 increases PM permeability, while higher H2O2 damages the PM during infection. Importantly, we found that gut commensal bacteria ensured proper Duox-dependent ROS production and PM stability, thus preventing Imd pathway overactivation in response to pathogens. We conclude that gut commensal bacteria-induced Duox-ROS is crucial for maintaining PM structural homeostasis, and the PM, in turn, regulates Imd pathway activation and protects intestinal epithelial cells. Thus, our study reveals a crosstalk between the PM barrier and Imd-mediated antibacterial function to ensure host defense in the gut.

Therapeutic Potential of Qilianxiaopi Formula: Targeting ADAM17-Mediated Chronic Inflammation in Atrophic Gastritis

Background: Gastric cancer (GC) is a leading cause of mortality worldwide, particularly in China. Chronic atrophic gastritis (CAG) and intestinal metaplasia (IM) are recognized as precancerous conditions contributing to GC development. Qilianxiaopi formula (QLXP), a traditional Chinese medicine (TCM), has demonstrated significant therapeutic effects on CAG and IM; however, its underlying mechanisms remain poorly understood. Methods: This study utilized chromatography-mass spectrometry to identify the major compounds in QLXP. Network pharmacology was used to predict the associated targets of these components. Thermal proteome profiling (TPP) pinpointed the potential binding proteins of QLXP, which were validated by bioinformatic analyses. Bio-layer interferometry (BLI) was used to analyze the interactions between QLXP and its key target proteins, thereby determining their binding components. Molecular docking predicted the binding modes between the components and proteins. Results: ADAM17 was identified as a key binding protein for QLXP. Further investigation revealed that QLXP inhibits the enzymatic activity of ADAM17, thereby reducing the secretion of the pro-inflammatory cytokine TNF-α, contributing to the anti-inflammatory properties of QLXP. BLI confirmed direct and reversible binding interactions between QLXP and ADAM17. Narirutin, isolated from the ADAM17 binding fraction, displayed the highest affinity for QLXP. Conclusions: This study highlights ADAM17 as a key molecular target of QLXP and narirutin as its principal binding component. The integrated approach combining chromatography-mass spectrometry, network pharmacology, TPP, BLI, and molecular docking provides a robust framework for elucidating the mechanisms of action of TCM.

Astroglial TNFR2 signaling regulates hippocampal synaptic function and plasticity in a sex dependent manner

Astrocytes participate in synaptic transmission and plasticity through tightly regulated, bidirectional communication with pre- and post-synaptic neurons, as well as microglia and oligodendrocytes. A key component of astrocyte-mediated synaptic regulation is the cytokine tumor necrosis factor (TNF). TNF signals via two cognate receptors, TNFR1 and TNFR2, both expressed in astrocytes. While TNFR1 signaling in astrocytes has been long demonstrated to be necessary for physiological synaptic function, the role of astroglial TNFR2 has never been explored. Here, we demonstrate that astroglial TNFR2 is essential for maintaining hippocampal synaptic function and plasticity in physiological conditions. Indeed, Gfap creERT2 :Tnfrsf1b fl/fl mice with selective ablation of TNFR2 in astrocytes exhibited dysregulated expression of neuronal and glial proteins (e.g., SNARE complex molecules, glutamate receptor subunits, glutamate transporters) essential for hippocampal synaptic transmission and plasticity. Hippocampal astrocytes sorted from Gfap creERT2 :Tnfrsf1b fl/fl mice displayed downregulation of genes and pathways implicated in synaptic plasticity, as well as astrocyte-neuron and astrocyte-oligodendrocyte communication. These alterations were accompanied by increased glial reactivity and impaired astrocyte calcium dynamics, and ultimately translated into functional deficits, specifically impaired long-term potentiation (LTP) and cognitive functions. Notably, male Gfap creERT2 :Tnfrsf1b fl/fl mice exhibited more pronounced hippocampal synaptic and cellular alterations, suggesting sex-dependent differences in astroglial TNFR2 regulation of synaptic function. Together, these findings indicate that TNFR2 signaling in astrocytes is essential for proper astrocyte-neuron communication at the basis of synaptic function, and that this is regulated in a sex-dependent manner.

Targeted delivery of TAPI-1 via biomimetic nanoparticles ameliorates post-infarct left ventricle function and remodeling

AIMS

The potential of nanoparticles as effective drug delivery tools for treating failing hearts in heart failure remains a challenge. Leveraging the rapid infiltration of neutrophils into infarcted hearts after myocardial infarction (MI), we developed a nanoparticle platform engineered with neutrophil-membrane proteins for the targeted delivery of TAPI-1, a TACE/ADAM17 inhibitor, to the inflamed myocardium, aiming to treat cardiac dysfunction and remodeling in rats with MI.

METHODS AND RESULTS

Neutrophil-mimic liposomal nanoparticles (Neu-LNPs) were constructed by integrating synthesized liposomal nanoparticles with LPS-stimulated neutrophil membrane fragments and then loaded with TAPI-1. MI rats were treated with TAPI-1 delivered via Neu-LNPs for 4 weeks. Left ventricular function was assessed by echocardiography and cardiac fibrosis was evaluated post-treatment. The novel Neu-LNPs maintained typical nanoparticle features, but with increased biocompatibility. Neu-LNPs demonstrated improved targeting ability and cellular internalization, facilitated by LFA1/Mac1/ICAM-1 interaction. Neu-LNPs displayed higher accumulation and cellular uptake by macrophages and cardiomyocytes in infarcted hearts post-MI, with a sustained duration. Treatments with TAPI-1-Neu-LNPs demonstrated greater protection against myocardial injury and cardiac dysfunction in MI rats compared to untargeted TAPI-1, along with reduced cardiac collagen deposition and expression of fibrosis biomarkers as well as altered immune cell compositions within the hearts.

CONCLUSIONS

Targeted treatment with TACE/ADAM17 inhibitor delivered via biomimetic nanoparticles exhibited pronounced advantages in improving left ventricle function, mitigating cardiac remodeling, and reducing inflammatory responses within the infarcted hearts. This study underscores the effectiveness of Neu-LNPs as a drug delivery strategy to enhance therapeutic efficacy in clinical settings.

Progress of ADAM17 in Fibrosis-Related Diseases

Fibrosis leads to structural damage and functional decline and is characterized by an accumulation of fibrous connective tissue and a reduction in parenchymal cells. Because of its extremely poor prognosis, organ fibrosis poses a significant economic burden. In order to prevent and treat fibrosis more effectively, potential mechanisms need to be investigated. A disintegrin and metalloprotease 17 (ADAM17) is a membrane-bound protein. It regulates intracellular signaling and membrane protein degradation. Fibrosis mediated by ADAM17 has been identified as an important contributor, although the specific relationship between its multiple regulatory functions and the pathogenesis is unclear. This article describes ADAM17 activation, function, and regulation, as well as the role of ADAM17 mediated fibrosis injury in kidney, liver, heart, lung, skin, endometrium, and retina. To develop new therapeutic approaches based on ADAM17 related signal pathways.

Soluble TIM-3, likely produced by myeloid cells, predicts resistance to immune checkpoint inhibitors in metastatic clear cell renal cell carcinoma

BACKGROUND

Immunotherapies targeting PD-1 and CTLA-4 are key components of the treatment of metastatic clear cell renal cell carcinoma (mccRCC). However, they have distinct safety profiles and resistance to treatment can occur. We assess soluble TIM-3 (sTIM-3) in the plasma of mccRCC patients as a potential theranostic biomarker, as well as its source and biological significance.

METHODS

We analyzed the association between sTIM-3 and overall survival (OS), tumor response, and common clinical and biological factors in two mccRCC cohorts treated with anti-PD-1 (nivolumab, n = 27), anti-PD-1 or anti-PD-1 + anti-CTLA-4 (nivolumab + ipilimumab - N + I, n = 124). The origin and role of sTIM-3 are studied on tumor and blood samples, using multiplex immunohistochemistry and flow cytometry, as well as analyses of publicly available single-cell transcriptomic (scRNAseq) and mass cytometry data.

RESULTS

sTIM-3 is significantly elevated in the plasma of treatment-naive mccRCC. It shows distinct associations with survival on anti-PD-1 vs anti-PD-1 + anti-CTLA-4: under nivolumab monotherapy, sTIM-3-high patients have a significantly reduced survival compared to sTIM-3-low patients, while they have similar survival probabilities under N + I. sTIM-3 is independent from other clinical and biological factors. Myeloid immune cells appear as the prominent source of sTIM-3, which may indicate their dysfunctional role in the antitumor immune response.

CONCLUSIONS

sTIM-3 appears to be a promising biomarker for optimizing treatment strategies in ccRCC as well as a potential therapeutic target, linked with to the immune myeloid compartment. Future investigations are warranted in patients treated with anti-PD-1 + antiangiogenic therapies.

Efficacy of Topical Cyclosporine Combined with Punctal Plugs in Treating Dry Eye Disease and Inflammation

PURPOSE

To evaluate the effect of punctal plugs combined with cyclosporine eye drops on dry eye disease (DED) and ocular surface inflammation.

METHODS

In a clinical trial, 73 patients were randomly allocated into three groups: punctal plug group, combination therapy group, and cyclosporine group. At the baseline and four weeks after treatment, the Schirmer I test score, fluorescein tear film break-up time (FBUT), ocular surface staining score and dry eye symptoms were assessed. Tear samples were collected to detect the level of inflammatory factors (interleukins, matrix metalloproteinase 9 (MMP-9) and tumor necrosis factor alpha (TNF-α)). In an animal experiment, a New Zealand rabbit dry eye model was induced. The rabbits were randomly divided into control group, punctal plug group, and combination therapy group (n = 6). Conjunctival goblet cell density, protein level of MMP-9 in conjunctiva and mRNA levels of inflammatory factors in conjunctiva and cornea were measured before and after treatment.

RESULTS

In combination therapy group of the clinical trial, the following results were observed: significant improvement in Schirmer I test scores and FBUT compared to the cyclosporine group and punctal plug group, respectively; a decrease in the tear levels of IL-6, IL-1, and MMP-9 compared to the punctal plug group; and a decrease in the tear levels of IL-1α, IL-6, and IL-17 compared to the baseline (all p < 0.05). In the animal experiment, rabbits in combination therapy group had a higher goblet cell density (p < 0.01) and lower mRNA levels of IL-16 (p < 0.05), IL-17 (p < 0.05), and MMP-9 (p < 0.01) in conjunctiva and that of MMP-9 (p < 0.01) in cornea compared to punctal plug group.

CONCLUSION

Cyclosporine eye drops combined with degradable punctal plugs is a more optimized clinical treatment strategy for DED compared with degradable punctal plugs or cyclosporine eye drops alone, considering the influence of comprehensive clinical efficacy and ocular surface inflammation.

Heart-derived factors and organ cross-talk in settings of health and disease: new knowledge and clinical opportunities for multimorbidity

Cardiovascular disease affects millions of people worldwide and often presents with other conditions including metabolic, renal and neurological disorders. A variety of secreted factors from multiple organs/tissues (proteins, nucleic acids and lipids) have been implicated in facilitating organ cross-talk that may contribute to the development of multimorbidity. Secreted proteins have received the most attention, with the greatest body of research related to factors released from adipose tissue (adipokines), followed by skeletal muscle (myokines). To date, there have been fewer studies on proteins released from the heart (cardiokines) implicated with organ cross-talk. Early evidence for the secretion of cardiac-specific factors facilitating organ cross-talk came in the form of natriuretic peptides which are secreted via the classical endoplasmic reticulum-Golgi pathway. More recently, studies in cardiomyocyte-specific genetic mouse models have revealed cardiac-initiated organ cross-talk. Cardiomyocyte-specific modulation of microRNAs (miR-208a and miR-23-27-24 cluster) and proteins such as the mediator complex subunit 13 (MED13), G-protein-coupled receptor kinase 2 (GRK2), mutant α-myosin heavy-chain (αMHC), ubiquitin-like modifier-activating enzyme (ATG7), oestrogen receptor alpha (ERα) and fibroblast growth factor 21 (FGF21) have resulted in metabolic and renal phenotypes. These studies have implicated a variety of factors which can be secreted via the classical pathway or via non-classical mechanisms including the release of extracellular vesicles. Cross-talk between the heart and the brain has also been described (e.g. via miR-1 and an emerging concept, interoception: detection of internal neural signals). Here we summarize these studies taking into consideration that factors may be secreted in both settings of health and in disease.

Exploring the mechanisms by which common inhalational anesthetics influence malignant tumor metastasis: A data mining study based on comparative toxicogenomic databases

Surgery remains the primary treatment for solid malignant tumors, but controlling postoperative tumor recurrence and metastasis continues to be a major challenge. Understanding the factors that influence tumor recurrence and metastasis after surgery, as well as the underlying biological mechanisms, is critical. Previous studies suggest that anesthetic agents may increase the risk of tumor recurrence and metastasis in patients with cancer, but the mechanisms underlying these findings remain unclear. In this study, we utilized toxicogenomics and comparative toxicogenomic databases to analyze data and explore the potential mechanisms by which three commonly used inhalational anesthetics-sevoflurane, isoflurane, and halothane-might promote malignant tumor metastasis. The results identified 18 genes that may be associated with tumor metastasis. Functional enrichment analysis revealed that these anesthetics could influence tumor cell migration by activating signaling pathways such as the IL-17 and tumor necrosis factor signaling pathways, thereby potentially inducing tumor metastasis. Moreover, by constructing a TF-mRNA network, we predicted several transcription factors that might play key roles in anesthetic-induced tumor metastasis. The analysis revealed a total of 87 regulatory relationships between transcription factors and mRNA. These findings offer new insights for future in vivo or in vitro studies and contribute to a better understanding of the relationship between inhalational anesthetics and tumor metastasis, providing valuable reference points for clinical decision-making. The results of this study also provide a reference for the determination of subsequent clinical treatment targets. Hence, future laboratory studies should prioritize investigating the specific genes and common mechanisms identified in this study.

Tumor Necrosis Factor Receptor 1 Is Required for Human Umbilical Cord-Derived Mesenchymal Stem Cell-Mediated Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a systemic, chronic inflammatory disease characterized by altered levels of inflammatory cytokines. One of the key cytokines involved in the pathogenesis of RA is tumor necrosis factor α (TNF-α), which plays a crucial role in the differentiation of T cells and B cells and serves as a primary trigger of inflammation and joint damage in RA. Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have shown potential in alleviating the symptoms of RA. Previous in vitro studies indicate that TNF-α secreted by T cells can activate NF-κB in human MSCs, thereby triggering the immunoregulatory capacity of MSCs in a manner dependent on tumor necrosis factor receptor 1 (TNFR1). Inspired by these findings, we aimed to evaluate whether TNFR1 determine the therapeutic effects of hUC-MSCs on RA. First, we investigated whether TNFR1 is necessary for hUC-MSCs to inhibit TNF-α production of PBMCs, a source of elevated TNF-α in patients. Through coculture experiment, we confirmed that this inhibition was dependent on TNFR1. Subsequently, we administered hUC-MSCs or siTNFR1-MSCs to DBA/1J male mice with collagen-induced arthritis. The results indicated that hUC-MSCs significantly alleviated the pathological features of RA and suppressed the inflammatory cytokines IFN-γ, TNF-α, and IL-6 in peripheral blood, also in a manner dependent on TNFR1 either. Given the dramatic pathologic differences between hUC-MSCs and siTNFR1-MSCs treatments, we questioned whether production of growth factors and chemokines was significantly influenced by TNFR1. Consequently, we stimulated hUC-MSCs or siTNFR1-MSCs through IFN-γ, TNF-α, and IL-6, and profiled growth factors and chemokines in serum, which revealed significant changes of hepatocyte growth factor (HGF) and keratinocyte growth factor (KGF), as well as chemokines CXCL9, CXCL10, IL-8, and RANTES. In summary, our findings suggest that TNFR1 may determine whether hUC-MSCs will gain abilities of anti-inflammation and tissue regeneration.

Updates on Inflammatory Molecular Pathways Mediated by ADAM17 in Autoimmunity

ADAM17 is a member of the disintegrin and metalloproteinase (ADAM) family of transmembrane proteases with immunoregulatory activity in multiple signaling pathways. The functional ADAM17 is involved in the shedding of the ectodomain characterizing many substrates belonging to growth factors, cytokines, receptors, and adhesion molecules. The ADAM17-dependent pathways are known to be crucial in tumor development and progression and in the modulation of many pathological and physiological processes. In the last decade, ADAM17 was considered the driver of several autoimmune pathologies, and numerous substrate-mediated signal transduction pathways were identified. However, the discoveries made to date have led researchers to try to clarify the multiple mechanisms in which ADAM17 is involved and to identify any molecular gaps between the different transductional cascades. In this review, we summarize the most recent updates on the multiple regulatory activities of ADAM17, focusing on reported data in the field of autoimmunity.

Serum ADAM17 levels pre-antiviral therapy correlate with HIV patient immune reconstitution

Background

The relationship between tumour necrosis factor (TNF) levels and disease progression is well-established. However, the impact of changes in the level of TNF hydrolase (A-disintegrin and metalloenzyme 17; ADAM17) in HIV patients remains to be fully elucidated.

Methods

Between March 1 and December 31, 2017, data were collected from 64 HIV-positive individuals in Wenzhou. Based on their history of antiviral treatment at the time of enrollment, these patients were categorized into two cohorts: an antiviral-treated group and an untreated HIV group. Then, the serum ADAM17 levels of each group were measured and analysed.

Results

In comparison to the antiviral-treated group and the control group, the untreated HIV group exhibited a significantly elevated serum ADAM17 level (p < 0.001). A significant negative correlation was observed between serum ADAM17 levels and CD4+ T cell counts in the untreated HIV group (r = -0.486, p = 0.001). ROC curve analysis revealed that the pre-treatment serum ADAM17 level in the untreated HIV group had moderate diagnostic accuracy for the AIDS stage (area under the curve: 0.703, p = 0.028). Additionally, serum ADAM17 levels were positively correlated with ADAM17 expression on the surface of leukocytes (r = 0.367, p = 0.018).

Conclusion

Serum ADAM17 levels are significantly elevated in HIV patients and are correlated with disease progression and immune reconstitution.

Neuroinflammation in Alzheimer disease

Increasing evidence points to a pivotal role of immune processes in the pathogenesis of Alzheimer disease, which is the most prevalent neurodegenerative and dementia-causing disease of our time. Multiple lines of information provided by experimental, epidemiological, neuropathological and genetic studies suggest a pathological role for innate and adaptive immune activation in this disease. Here, we review the cell types and pathological mechanisms involved in disease development as well as the influence of genetics and lifestyle factors. Given the decade-long preclinical stage of Alzheimer disease, these mechanisms and their interactions are driving forces behind the spread and progression of the disease. The identification of treatment opportunities will require a precise understanding of the cells and mechanisms involved as well as a clear definition of their temporal and topographical nature. We will also discuss new therapeutic strategies for targeting neuroinflammation, which are now entering the clinic and showing promise for patients.

Repurposing raltegravir for reducing inflammation and treating cancer: a bioinformatics analysis

Inflammation is a defensive mechanism that safeguards the human body against detrimental stimuli. Within this intricate process, ADAM17, a zinc-dependent metalloprotease, emerges as an indispensable element, fostering the activation of diverse inflammatory and growth factors within the organism. Nonetheless, ADAM17 malfunctions can augment the rate of growth, inflammatory factors, and subsequent damage. Thus, in this study, we examined and repurposed drugs to suppress the activity of ADAM17. To this end, we employed bioinformatics techniques such as molecular docking, molecular dynamics, and pharmacokinetic studies. Five FDA-approved drugs including Raltegravir, Conivaptan, Paclitaxel, Saquinavir, and Venetoclax with the ability to impede the activity of the ADAM17 metalloenzyme were identified. Moreover, these drugs did not include strong zinc-binding functional groups when verified by the ACE functional group finder. However, further in silico analysis has indicated that Raltegravir demonstrates a commendable interaction with the active site amino acids and exhibits the most favorable pharmacokinetic properties compared to others. Considering the results of bioinformatics tools, it can be concluded that Raltegravir as an antiviral drug could be repurposed to prevent severe inflammatory response and tumorigenesis resulting from ADAM17 malfunction.

Inhibition of ADAM17 attenuates high glucose-induced angiogenesis and inflammation in endothelial cells partly through down-regulation of GRO-α/CXCR2 expression: implications in peritoneal dialysis

BACKGROUND

Angiogenesis and inflammation are key events leading to peritoneal morphologic alteration and ultrafiltration failure in patients undergoing peritoneal dialysis (PD). The current study aims to explore the role of ADAM17 in the angiogenetic and inflammatory responses of endothelial cells.

METHODS

Human umbilical vein endothelial cells (HUVECs) were cultured and treated with a high glucose-containing medium. In parallel experiments, the expression of ADAM17 in HUVECs was inhibited by SiRNA interference. The mRNA and protein expression of ADAM17, GRO-α and CXCR2 were assessed by qPCR and Western blotting, respectively. The concentrations of GRO-α, VEGF, IL-6 and TNF-α in the cellular supernatants were determined by ELISA. Tube formation and migration of HUVECs were evaluated by Matrigel and transwell migration apparatus.

RESULTS

High glucose increased the expression of ADAM17, CXCR2 and GRO-α in cultured HUVECs. RNA silencing of ADAM17 abolished high glucose-mediated increase of GRO-α and CXCR2, which were accompanied by reduced secretion of VEGF, IL-6, TNF-α, as well as tube formation and cell migration in HUVECs.

CONCLUSIONS

Inhibition of ADAM17 ameliorates high glucose-induced angiogenic and inflammatory responses in endothelial cells partly through down-regulation of GRO-α/CXCR2 expression.

Development of a Proteomic Workflow for the Identification of Heparan Sulphate Proteoglycan-Binding Substrates of ADAM17

Ectodomain shedding, which is the proteolytic release of transmembrane proteins from the cell surface, is crucial for cell-to-cell communication and other biological processes. The metalloproteinase ADAM17 mediates ectodomain shedding of over 50 transmembrane proteins ranging from cytokines and growth factors, such as TNF and EGFR ligands, to signalling receptors and adhesion molecules. Yet, the ADAM17 sheddome is only partly defined and biological functions of the protease have not been fully characterized. Some ADAM17 substrates (e.g., HB-EGF) are known to bind to heparan sulphate proteoglycans (HSPG), and we hypothesised that such substrates would be under-represented in traditional secretome analyses, due to their binding to cell surface or pericellular HSPGs. Thus, to identify novel HSPG-binding ADAM17 substrates, we developed a proteomic workflow that involves addition of heparin to solubilize HSPG-binding proteins from the cell layer, thereby allowing their mass spectrometry detection by heparin-treated secretome (HEP-SEC) analysis. Applying this methodology to murine embryonic fibroblasts stimulated with an ADAM17 activator enabled us to identify 47 transmembrane proteins that were shed in response to ADAM17 activation. This included known HSPG-binding ADAM17 substrates (i.e., HB-EGF, CX3CL1) and 14 novel HSPG-binding putative ADAM17 substrates. Two of these, MHC-I and IL1RL1, were validated as ADAM17 substrates by immunoblotting.

Understanding the role of TNFR2 signaling in the tumor microenvironment of breast cancer

Breast cancer (BC) is the most frequently diagnosed malignancy among women. It is characterized by a high level of heterogeneity that emerges from the interaction of several cellular and soluble components in the tumor microenvironment (TME), such as cytokines, tumor cells and tumor-associated immune cells. Tumor necrosis factor (TNF) receptor 2 (TNFR2) appears to play a significant role in microenvironmental regulation, tumor progression, immune evasion, drug resistance, and metastasis of many types of cancer, including BC. However, the significance of TNFR2 in BC biology is not fully understood. This review provides an overview of TNFR2 biology, detailing its activation and its interactions with important signaling pathways in the TME (e.g., NF-κB, MAPK, and PI3K/Akt pathways). We discuss potential therapeutic strategies targeting TNFR2, with the aim of enhancing the antitumor immune response to BC. This review provides insights into role of TNFR2 as a major immune checkpoint for the future treatment of patients with BC.

Inflammation and Related Signaling Pathways in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy, and inflammatory signaling is involved in its pathogenesis. Cytokines exert a robust effect on the progression of AML and affect survival outcomes. The dysregulation in the cytokine network may foster a pro-tumorigenic microenvironment, increasing leukemic cell proliferation, decreasing survival and driving drug resistance. The dominance of pro-inflammatory mediators such as IL-11β, TNF-α and IL-6 over anti-inflammatory mediators such as TGF-β and IL-10 has been implicated in tumor progression. Additionally, inflammatory cytokines have favored certain populations of hematopoietic stem and progenitor cells with mutated clonal hematopoiesis genes. This article summarizes current knowledge about inflammatory cytokines and signaling pathways in AML, their modes of action and the implications for immune tolerance and clonal hematopoiesis, with the aim of finding potential therapeutic interventions to improve clinical outcomes in AML patients.

Role of ADAM10/17-Mediated Cleavage of LAG3 in the Impairment of Immunosuppression in Psoriasis

Despite extensive research on immune activation regulatory mechanisms, studies on immune suppression in psoriasis are limited. LAG3, a newly identified immune checkpoint, plays a crucial role in modulating immune responses and maintaining T-regulatory cell function. However, its involvement in psoriasis is unclear. We show that psoriasis is associated with reduced LAG3 expression in CD4 T cells and T-regulatory cells. Further analysis revealed that the decline in LAG3 levels was linked to ADAM10/17-mediated proteolytic cleavage, which was upregulated in psoriasis. Clinical utilization of the IL-17A antagonist secukinumab, along with the in vivo and in vitro IL-17A-induced models, supported the potential of IL-17A to induce ADAM10/17 expression and trigger LAG3 cleavage. Through the Jurkat cell model, IL-17A was found to regulate ADAM10/17 expression by activating FOXM1. In addition, treatment with the ADAM10/17 inhibitor GW280264X showed ameliorative effects on psoriasis-like mouse models and lipopolysaccharide-induced inflammation. Collectively, the findings of this study uncover the immune regulatory role of the ADAM10/17-LAG3 axis in psoriasis and highlight the therapeutic potential of targeting ADAM10/17 for psoriasis treatment.

Synthetic and non-synthetic inhibition of ADAM10 and ADAM17 reduces inflammation and oxidative stress in LPS-induced acute kidney injury in male and female mice

Acute kidney injury (AKI) is a severe medical condition that can lead to illness and death. A disintegrin and metalloprotease (ADAM) protein family is a potential treatment target for AKI due to its involvement in inflammation, growth, and differentiation. While ADAM10 and ADAM17 have been identified as significant contributors to inflammation, it is unclear whether they play a critical role in AKI. In this study, we induced AKI in male and female mice using lipopolysaccharide, a bacterial endotoxin that causes inflammation and oxidative stress. The role of kaempferol, which is found in many natural products and known to have antioxidant and anti-inflammatory activity in many pre-clinical studies, was investigated through ADAM10/17 enzymes in AKI. We also investigated the efficacy of a selective synthetic inhibitor named GW280264X for ADAM10/17 inhibition in AKI. Blood urea nitrogen and creatinine levels were measured in serum, while tumor necrosis factor-α, vascular adhesion molecule, interleukin (IL)-1β, glucose regulatory protein-78, IL-10, nuclear factor κ-B, thiobarbituric acid reactive substances, total thiol, ADAM10, and ADAM17 levels were measured in kidney tissue. We also evaluated kidney tissue histologically using hematoxylin and eosin, periodic acid-schiff, and caspase-3 staining. This research demonstrates that GW280264X and kaempferol reduces inflammation and oxidative stress, as evidenced by biochemical and histopathological results in AKI through ADAM10/17 inhibition. These findings suggest that inhibiting ADAM10/17 may be a promising therapeutic approach for treating acute kidney injury.

iRhom2 deficiency reduces sepsis-induced mortality associated with the attenuation of lung macrophages in mice

Sepsis has a high mortality rate and leads to multi-organ failure, including lung injury. Inactive rhomboid protease family protein (iRhom2) has been identified as accountable for the release of TNF-α, a crucial mediator in the development of sepsis. This study aimed to evaluate the role of iRhom2 in sepsis and sepsis-induced acute lung injury (ALI). TNF-α and IL-6 secretion in vitro by peritoneal macrophages from wild-type (WT) and iRhom2 knoukout (KO) mice was assessed by enzyme-linked immunosorbent assay. Cecal ligation and puncture (CLP)-induced murine sepsis model was used for in vivo experiments. To evaluate the role of iRhom2 deficiency on survival during sepsis, both WT and iRhom2 KO mice were monitored for 8 consecutive days following the CLP. For histologic and biochemical examination, the mice were killed 18 h after CLP. iRhom2 deficiency improved the survival of mice after CLP. iRhom2 deficiency decreased CD68+ macrophage infiltration in lung tissues. Multiplex immunohistochemistry revealed that the proportion of Ki-67+ CD68+ macrophages was significantly lower in iRhom2 KO mice than that in WT mice after CLP. Moreover, CLP-induced release of TNF-α and IL-6 in the serum were significantly inhibited by iRhom2 deficiency. iRhom2 deficiency reduced NF-kB p65 and IκBα phosphorylation after CLP. iRhom2 deficiency reduces sepsis-related mortality associated with attenuated macrophage infiltration and proliferation in early lung injury. iRhom2 may play a pivotal role in the pathogenesis of sepsis and early stage of sepsis-induced ALI. Thus, iRhom2 may be a potential therapeutic target for the management of sepsis and sepsis-induced ALI.

Discovery of Cyclic Peptide Inhibitors Targeted on TNFα-TNFR1 from Computational Design and Bioactivity Verification

Activating tumor necrosis factor receptor 1 (TNFR1) with tumor necrosis factor alpha (TNFα) is one of the key pathological mechanisms resulting in the exacerbation of rheumatoid arthritis (RA) immune response. Despite various types of drugs being available for the treatment of RA, a series of shortcomings still limits their application. Therefore, developing novel peptide drugs that target TNFα-TNFR1 interaction is expected to expand therapeutic drug options. In this study, the detailed interaction mechanism between TNFα and TNFR1 was elucidated, based on which, a series of linear peptides were initially designed. To overcome its large conformational flexibility, two different head-to-tail cyclization strategies were adopted by adding a proline-glycine (GP) or cysteine-cysteine (CC) to form an amide or disulfide bond between the N-C terminal. The results indicate that two cyclic peptides, R1_CC4 and α_CC8, exhibit the strongest binding free energies. α_CC8 was selected for further optimization using virtual mutations through in vitro activity and toxicity experiments due to its optimal biological activity. The L16R mutant was screened, and its binding affinity to TNFR1 was validated using ELISA assays. This study designed a novel cyclic peptide structure with potential anti-inflammatory properties, possibly bringing an additional choice for the treatment of RA in the future.

Decoy peptides that inhibit TNF signaling by disrupting the TNF homotrimeric oligomer

Tumor necrosis factor (TNF) is a pro-inflammatory cytokine and its functional homotrimeric form interacts with the TNF receptor (TNFR) to activate downstream apoptotic, necroptotic, and inflammatory signaling pathways. Excessive activation of these pathways leads to various inflammatory diseases, which makes TNF a promising therapeutic target. Here, 12-mer peptides were selected from the interface of TNF-TNFR based upon their relative binding energies and were named 'TNF-inhibiting decoys' (TIDs). These decoy peptides inhibited TNF-mediated secretion of cytokines and cell death, as well as activation of downstream signaling effectors. Effective TIDs inhibited TNF signaling by disrupting the formation of TNF's functional homotrimeric form. Among derivatives of TIDs, TID3c showed slightly better efficacy in cell-based assays by disrupting TNF trimer formation. Moreover, TID3c oligomerized TNF to a high molecular weight configuration. In silico modeling and simulations revealed that TID3c and its parent peptide, TID3, form a stable complex with TNF through hydrogen bonds and electrostatic interactions, which makes them the promising lead to develop peptide-based anti-TNF therapeutics.

Targeting iRhom2/ADAM17 attenuates COVID-19-induced cytokine release from cultured lung epithelial cells

The COVID-19 pandemic, caused by SARS-CoV-2, continues to pose a significant global health challenge, with acute respiratory distress syndrome (ARDS) being a major cause of mortality. Excessive cytokine release (cytokine storm) has been causally related to COVID-19-associated ARDS. While TNF-α inhibitors have shown potential in reducing inflammation, their broad effects on TNF-α signaling, including both pro- and anti-inflammatory pathways, present significant challenges and side effects in clinical use. Therefore, more precise therapeutic targets are urgently needed. ADAM17 is a key enzyme driving cytokine release, but its broad presence complicates direct inhibition. Targeting iRhom2, a regulator specific to immune cells that controls ADAM17's activity, offers a more focused and effective approach to reducing cytokine release. In this study, we hypothesized that targeted inhibition of ADAM-17/iRhom2 attenuates COVID-19-induced cytokine release in cultured lung epithelial cells. Human primary bronchial/tracheal epithelial cells challenged with COVID-19 pseudo-viral particles resulted in elevated cytokine release, which was attenuated following siRNA-mediated silencing of ADAM17 and iRhom2. Targeting ADAM-17/iRhom2 pathway may thus represent a strategy to overcome the COVID-19-associated ARDS.

Stimulating the Antitumor Immune Response Using Immunocytokines: A Preclinical and Clinical Overview

Cytokines are immune modulators which can enhance the immune response and have been proven to be an effective class of immunotherapy. Nevertheless, the clinical use of cytokines in cancer treatment has faced several challenges associated with poor pharmacokinetic properties and the occurrence of adverse effects. Immunocytokines (ICKs) have emerged as a promising approach to overcome the pharmacological limitations observed with cytokines. ICKs are fusion proteins designed to deliver cytokines in the tumor microenvironment by taking advantage of the stability and specificity of immunoglobulin-based scaffolds. Several technological approaches have been developed. This review focuses on ICKs designed with the most impactful cytokines in the cancer field: IL-2, TNFα, IL-10, IL-12, IL-15, IL-21, IFNγ, GM-CSF, and IFNα. An overview of the pharmacological effects of the naked cytokines and ICKs tested for cancer therapy is detailed. A particular emphasis is given on the immunomodulatory effects of ICKs associated with their technological design. In conclusion, this review highlights active ways of development of ICKs. Their already promising results observed in clinical trials are likely to be improved with the advances in targeting technologies such as cytokine/linker engineering and the design of multispecific antibodies with tumor targeting and immunostimulatory functional properties.

Enhanced IL-15-mediated NK cell activation and proliferation by an ADAM17 function-blocking antibody involves CD16A, CD137, and accessory cells

BACKGROUND

Natural killer (NK) cells are being extensively studied as a cell therapy for cancer. These cells are activated by recognition of ligands and antigens on tumor cells. Cytokine therapies, such as IL-15, are also broadly used to stimulate endogenous and adoptively transferred NK cells in patients with cancer. These stimuli activate the membrane protease ADAM17, which cleaves various cell-surface receptors on NK cells as a negative feedback loop to limit their cytolytic function. ADAM17 inhibition can enhance IL-15-mediated NK cell proliferation in vitro and in vivo. In this study, we investigated the underlying mechanism of this process.

METHODS

Peripheral blood mononuclear cells (PBMCs) or enriched NK cells from human peripheral blood, either unlabeled or labeled with a cell proliferation dye, were cultured for up to 7 days in the presence of rhIL-15±an ADAM17 function-blocking antibody. Different fully human versions of the antibody were generated; Medi-1 (IgG1), Medi-4 (IgG4), Medi-PGLALA, Medi-F(ab')2, and TAB16 (anti-ADAM17 and anti-CD16 bispecific) to modulate CD16A binding. Flow cytometry was used to assess NK cell proliferation and phenotypic markers, immunoblotting to examine CD16A signaling, and IncuCyte-based live cell imaging to measure NK cell antitumor activity.

RESULTS

The ADAM17 function-blocking monoclonal antibody (mAb) Medi-1 markedly increased early NK cell activation by IL-15. By using different engineered versions of the antibody, we demonstrate involvement by CD16A, an activating Fcγ receptor and well-described ADAM17 substrate. Hence, Medi-1 when bound to ADAM17 on NK cells is engaged by CD16A and blocks its shedding, inducing and prolonging its signaling. This process did not promote evident NK cell fratricide or dysfunction. Synergistic signaling by Medi-1 and IL-15 enhanced the upregulation of CD137 on CD16A+ NK cells and augmented their proliferation in the presence of PBMC accessory cells or an anti-CD137 agonistic mAb.

CONCLUSIONS

Our data reveal for the first time that CD16A and CD137 underpin Medi-1 enhancement of IL-15-driven NK cell activation and proliferation, respectively, with the latter requiring PBMC accessory cells. The use of Medi-1 represents a novel strategy to enhance IL-15-driven NK cell proliferation, and it may be of therapeutic importance by increasing the antitumor activity of NK cells in patients with cancer.

Aprotinin (I): Understanding the Role of Host Proteases in COVID-19 and the Importance of Pharmacologically Regulating Their Function

Proteases are produced and released in the mucosal cells of the respiratory tract and have important physiological functions, for example, maintaining airway humidification to allow proper gas exchange. The infectious mechanism of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), takes advantage of host proteases in two ways: to change the spatial conformation of the spike (S) protein via endoproteolysis (e.g., transmembrane serine protease type 2 (TMPRSS2)) and as a target to anchor to epithelial cells (e.g., angiotensin-converting enzyme 2 (ACE2)). This infectious process leads to an imbalance in the mucosa between the release and action of proteases versus regulation by anti-proteases, which contributes to the exacerbation of the inflammatory and prothrombotic response in COVID-19. In this article, we describe the most important proteases that are affected in COVID-19, and how their overactivation affects the three main physiological systems in which they participate: the complement system and the kinin-kallikrein system (KKS), which both form part of the contact system of innate immunity, and the renin-angiotensin-aldosterone system (RAAS). We aim to elucidate the pathophysiological bases of COVID-19 in the context of the imbalance between the action of proteases and anti-proteases to understand the mechanism of aprotinin action (a panprotease inhibitor). In a second-part review, titled "Aprotinin (II): Inhalational Administration for the Treatment of COVID-19 and Other Viral Conditions", we explain in depth the pharmacodynamics, pharmacokinetics, toxicity, and use of aprotinin as an antiviral drug.

MicroRNAs as the pivotal regulators of Temozolomide resistance in glioblastoma

Glioblastoma (GBM) is an aggressive nervous system tumor with a poor prognosis. Although, surgery, radiation therapy, and chemotherapy are the current standard protocol for GBM patients, there is still a poor prognosis in these patients. Temozolomide (TMZ) as a first-line therapeutic agent in GBM can easily cross from the blood-brain barrier to inhibit tumor cell proliferation. However, there is a high rate of TMZ resistance in GBM patients. Since, there are limited therapeutic choices for GBM patients who develop TMZ resistance; it is required to clarify the molecular mechanisms of chemo resistance to introduce the novel therapeutic targets. MicroRNAs (miRNAs) regulate chemo resistance through regulation of drug metabolism, absorption, DNA repair, apoptosis, and cell cycle. In the present review we discussed the role of miRNAs in TMZ response of GBM cells. It has been reported that miRNAs mainly induced TMZ sensitivity by regulation of signaling pathways and autophagy in GBM cells. Therefore, miRNAs can be used as the reliable diagnostic/prognostic markers in GBM patients. They can also be used as the therapeutic targets to improve the TMZ response in GBM cells.

Microglial TNFα controls daily changes in synaptic GABAARs and sleep slow waves

Microglia sense the changes in their environment. How microglia actively translate these changes into suitable cues to adapt brain physiology is unknown. We reveal an activity-dependent regulation of cortical inhibitory synapses by microglia, driven by purinergic signaling acting on P2RX7 and mediated by microglia-derived TNFα. We demonstrate that sleep induces microglia-dependent synaptic enrichment of GABAARs in a manner dependent on microglial TNFα and P2RX7. We further show that microglia-specific depletion of TNFα alters slow waves during NREM sleep and blunt memory consolidation in sleep-dependent learning tasks. Together, our results reveal that microglia orchestrate sleep-intrinsic plasticity of synaptic GABAARs, sculpt sleep slow waves, and support memory consolidation.

A Disintegrin And Metalloprotease 10 expression within the murine central nervous system

A Disintegrin And Metalloprotease 10 (ADAM10), is able to control several important physiopathological processes through the shedding of a large number of protein substrates. Although ADAM10 plays a crucial role in the central nervous system (CNS) development and function, its protein distribution in the CNS has not been fully addressed. Here, we described the regional and cellular ADAM10 protein expression in C57BL/6 mice examined by immunofluorescence 1) throughout the adult mouse brain, cerebellum and spinal cord in vivo and 2) in different cell types as neurons, astrocytes, oligodendrocytes and microglia in vitro. We observed ADAM10 expression through the whole CNS, with a strong expression in the hippocampus, in the hypothalamus and in the cerebral and piriform cortex in the brain, in the Purkinje and in granular cell layers in the cerebellum and in the spinal cord to a lower extent. In vivo, ADAM10 protein expression was mainly found in neurons and in some oligodendroglial cell populations. However, in primary cultures we observed ADAM10 expression in neurons, oligodendrocytes, astrocytes and microglia. Interestingly, ADAM10 was not only found in the membrane but also in cytoplasmic vesicles and in the nucleus of primary cultured cells. Overall, this work highlights a wide distribution of ADAM10 throughout the CNS. The nuclear localization of ADAM10, probably due to its intracellular domain, emphasizes its role in cell signalling in physiological and pathological conditions. Further investigations are required to better elucidate the role of ADAM10 in glial cells.

Cryo-EM reveals that iRhom2 restrains ADAM17 protease activity to control the release of growth factor and inflammatory signals

A disintegrin and metalloprotease 17 (ADAM17) is a membrane-tethered protease that triggers multiple signaling pathways. It releases active forms of the primary inflammatory cytokine tumor necrosis factor (TNF) and cancer-implicated epidermal growth factor (EGF) family growth factors. iRhom2, a rhomboid-like, membrane-embedded pseudoprotease, is an essential cofactor of ADAM17. Here, we present cryoelectron microscopy (cryo-EM) structures of the human ADAM17/iRhom2 complex in both inactive and active states. These reveal three regulatory mechanisms. First, exploiting the rhomboid-like hallmark of TMD recognition, iRhom2 interacts with the ADAM17 TMD to promote ADAM17 trafficking and enzyme maturation. Second, a unique iRhom2 extracellular domain unexpectedly retains the cleaved ADAM17 inhibitory prodomain, safeguarding against premature activation and dysregulated proteolysis. Finally, loss of the prodomain from the complex mobilizes the ADAM17 protease domain, contributing to its ability to engage substrates. Our results reveal how a rhomboid-like pseudoprotease has been repurposed during evolution to regulate a potent membrane-tethered enzyme, ADAM17, ensuring the fidelity of inflammatory and growth factor signaling.

The rs11684747 and rs55790676 SNPs of ADAM17 influence tuberculosis susceptibility and plasma levels of TNF, TNFR1, and TNFR2

Introduction

The proteolytic activity of A Disintegrin and Metalloproteinase 17 (ADAM17) regulates the release of tumor necrosis factor (TNF) and TNF receptors (TNFRs) from cell surfaces. These molecules play important roles in tuberculosis (TB) shaping innate immune reactions and granuloma formation.

Methods

Here, we investigated whether single nucleotide polymorphisms (SNPs) of ADAM17 influence TNF and TNFRs levels in 224 patients with active TB (ATB) and 118 healthy close contacts. Also, we looked for significant associations between SNPs of ADAM17 and ATB status. TNF, TNFR1, and TNFR2 levels were measured in plasma samples by ELISA. Four SNPs of ADAM17 (rs12692386, rs1524668, rs11684747, and rs55790676) were analyzed in DNA isolated from peripheral blood leucocytes. The association between ATB status, genotype, and cytokines was analyzed by multiple regression models.

Results

Our results showed a higher frequency of rs11684747 and rs55790676 in close contacts than ATB patients. Coincidentally, heterozygous to these SNPs of ADAM17 showed higher plasma levels of TNF compared to homozygous to their respective ancestral alleles. Strikingly, the levels of TNF and TNFRs distinguished participant groups, with ATB patients displaying lower TNF and higher TNFR1/TNFR2 levels compared to their close contacts.

Conclusion

These findings suggest a role for SNPs of ADAM17 in genetic susceptibility to ATB.

Role of iRhom2 in Olfaction: Implications for Odorant Receptor Regulation and Activity-Dependent Adaptation

The cell surface metalloprotease ADAM17 (a disintegrin and metalloprotease 17) and its binding partners iRhom2 and iRhom1 (inactive Rhomboid-like proteins 1 and 2) modulate cell-cell interactions by mediating the release of membrane proteins such as TNFα (Tumor necrosis factor α) and EGFR (Epidermal growth factor receptor) ligands from the cell surface. Most cell types express both iRhoms, though myeloid cells exclusively express iRhom2, and iRhom1 is the main iRhom in the mouse brain. Here, we report that iRhom2 is uniquely expressed in olfactory sensory neurons (OSNs), highly specialized cells expressing one olfactory receptor (OR) from a repertoire of more than a thousand OR genes in mice. iRhom2-/- mice had no evident morphological defects in the olfactory epithelium (OE), yet RNAseq analysis revealed differential expression of a small subset of ORs. Notably, while the majority of ORs remain unaffected in iRhom2-/- OE, OSNs expressing ORs that are enriched in iRhom2-/- OE showed fewer gene expression changes upon odor environmental changes than the majority of OSNs. Moreover, we discovered an inverse correlation between the expression of iRhom2 compared to OSN activity genes and that odor exposure negatively regulates iRhom2 expression. Given that ORs are specialized G-protein coupled receptors (GPCRs) and many GPCRs activate iRhom2/ADAM17, we investigated if ORs could activate iRhom2/ADAM17. Activation of an olfactory receptor that is ectopically expressed in keratinocytes (OR2AT4) by its agonist Sandalore leads to ERK1/2 phosphorylation, likely via an iRhom2/ADAM17-dependent pathway. Taken together, these findings point to a mechanism by which odor stimulation of OSNs activates iRhom2/ADAM17 catalytic activity, resulting in downstream transcriptional changes to the OR repertoire and activity genes, and driving a negative feedback loop to downregulate iRhom2 expression.

In vitro cleavage of tumor necrosis factor α (TNFα) by Signal-Peptide-Peptidase-like 2b (SPPL2b) resembles mechanistic principles observed in the cellular context

Members of the Signal Peptide-Peptidase (SPP) and Signal Peptide-Peptidase-like (SPPL) family are intramembrane aspartyl-proteases like their well-studied homologs, the presenilins, which comprise the catalytically active subunit within the γ-secretase complex. The lack of in vitro cleavage assays for SPPL proteases limited their biochemical characterization as well as substrate identification and validation. So far, SPPL proteases have been analyzed exclusively in intact cells or membranes, restricting mechanistic analysis to co-expression of enzyme and substrate variants colocalizing in the same subcellular compartments. We describe the details of developing an in vitro cleavage assay for SPPL2b and its model substrate TNFα and analyzed the influence of phospholipids, detergent supplements, and cholesterol on the SPPL2b in vitro activity. SPPL2b in vitro activity resembles mechanistic principles that have been observed in a cellular context, such as cleavage sites and consecutive turnover of the TNFα transmembrane domain. The novel in vitro cleavage assay is functional with separately isolated protease and substrate and amenable to a high throughput plate-based readout overcoming previous limitations and providing the basis for studying enzyme kinetics, catalytic activity, substrate recognition, and the characteristics of small molecule inhibitors. As a proof of concept, we present the first biochemical in vitro characterization of the SPPL2a and SPPL2b specific small molecule inhibitor SPL-707.

Enhanced IL-15-mediated NK cell activation and proliferation by an ADAM17 function-blocking antibody involves CD16A, CD137, and accessory cells

Background

NK cells are being extensively studied as a cell therapy for cancer. Their effector functions are induced by the recognition of ligands on tumor cells and by various cytokines. IL-15 is broadly used to stimulate endogenous and adoptively transferred NK cells in cancer patients. These stimuli activate the membrane protease ADAM17, which then cleaves assorted receptors on the surface of NK cells as a negative feedback loop to limit their activation and function. We have shown that ADAM17 inhibition can enhance IL-15-mediated NK cell proliferation in vitro and in vivo . In this study, we investigated the underlying mechanism of this process.

Methods

PBMCs or enriched NK cells from human peripheral blood, either unlabeled or labeled with a cell proliferation dye, were cultured for up to 7 days in the presence of rhIL-15 +/- an ADAM17 function-blocking antibody. Different versions of the antibody were generated; Medi-1 (IgG1), Medi-4 (IgG4), Medi-PGLALA, Medi-F(ab') 2 , and TAB16 (anti-ADAM17 and anti-CD16 bispecific) to modulate CD16A engagement on NK cells. Flow cytometry was used to assess NK cell proliferation and phenotypic markers, immunoblotting to examine CD16A signaling, and IncuCyte-based live cell imaging to measure NK cell anti-tumor activity.

Results

The ADAM17 function-blocking mAb Medi-1 markedly increased initial NK cell activation by IL-15. Using different engineered versions of the antibody revealed that the activating Fcγ receptor CD16A, a well-described ADAM17 substrate, was critical for enhancing IL-15 stimulation. Hence, Medi-1 bound to ADAM17 on NK cells can be engaged by CD16A and block its shedding, inducing and prolonging its signaling. This process did not promote evident NK cell fratricide, phagocytosis, or dysfunction. Synergistic activity by Medi-1 and IL-15 enhanced the upregulation of CD137 on CD16A + NK cells and augmented their proliferation in the presence of PBMC accessory cells.

Conclusions

Our data reveal for the first time that CD16A and CD137 underpin Medi-1 enhancement of IL-15-driven NK cell activation and proliferation, respectively. The use of Medi-1 represents a novel strategy to enhance IL-15-driven NK cell proliferation, and it may be of therapeutic importance by increasing the anti-tumor activity of NK cells in cancer patients.

What is already known on this topic

NK cell therapies are being broadly investigated to treat cancer. NK cell stimulation by IL-15 prolongs their survival in cancer patients. Various stimuli including IL-15 activate ADAM17 in NK cells, a membrane protease that regulates the cell surface density of various receptors as a negative feedback mechanism.

What this study adds

Treating NK cells with the ADAM17 function-blocking mAb Medi-1 markedly enhanced their activation and proliferation. Our study reveals that the Fc and Fab regions of Medi-1 function synergistically with IL-15 in NK cell activation. Medi-1 treatment augments the upregulation of CD137 by NK cells, which enhances their proliferation in the presence of PBMC accessory cells.

How this study might affect research practice or policy

Our study is of translational importance as Medi-1 treatment in combination with IL-15 could potentially augment the proliferation and function of endogenous or adoptively transferred NK cells in cancer patients.

Graphical abstract

Soluble Plasma Proteins of Tumor Necrosis Factor and Immunoglobulin Superfamilies Reveal New Insights into Immune Regulation in People with HIV and Opioid Use Disorder

People with HIV (PWH) frequently suffer from Opioid (OP) Use Disorder (OUD). In an investigation of the impact of OUD on underlying immune dysfunction in PWH, we previously reported that OP use exacerbates inflammation in virally controlled PWH followed in the Infectious Diseases Elimination Act (IDEA) Syringe Services Program (SSP). Unexpectedly, Flu vaccination-induced antibody responses in groups with OUD were superior to PWH without OUD. Here, we investigated the profile of 48 plasma biomarkers comprised of TNF and Ig superfamily (SF) molecules known to impact interactions between T and B cells in 209 participants divided into four groups: (1) HIV+OP+, (2) HIV-OP+, (3) HIV+OP-, and (4) HIV-OP-. The differential expression of the top eight molecules ranked by median values in individual Groups 1-3 in comparison to Group 4 was highly significant. Both OP+ groups 1 and 2 had higher co-stimulatory TNF SF molecules, including 4-1BB, OX-40, CD40, CD30, and 4-1BBL, which were found to positively correlate with Flu Ab titers. In contrast, HIV+OP- exhibited a profile dominant in Ig SF molecules, including PDL-2, CTLA-4, and Perforin, with PDL-2 showing a negative correlation with Flu vaccine titers. These findings are relevant to vaccine development in the fields of HIV and OUD.

Role of the prefrontal cortical protease TACE/ADAM17 in neurobehavioral responses to chronic stress during adolescence

INTRODUCTION

Chronic adolescent stress profoundly affects prefrontal cortical networks regulating top-down behavior control. However, the neurobiological pathways contributing to stress-induced alterations in the brain and behavior remain largely unknown. Chronic stress influences brain growth factors and immune responses, which may, in turn, disrupt the maturation and function of prefrontal cortical networks. The tumor necrosis factor alpha-converting enzyme/a disintegrin and metalloproteinase 17 (TACE/ADAM17) is a sheddase with essential functions in brain maturation, behavior, and inflammatory responses. This study aimed to determine the impact of stress on the prefrontal cortex and whether TACE/ADAM17 plays a role in these responses.

METHODS

We used a Lewis rat model that incorporates critical elements of chronic psychosocial stress, such as uncontrollability, unpredictability, lack of social support, and re-experiencing of trauma.

RESULTS

Chronic stress during adolescence reduced the acoustic startle reflex and social interactions while increasing extracellular free water content and TACE/ADAM17 mRNA levels in the medial prefrontal cortex. Chronic stress altered various ethological behavioral domains in the observation home cages (decreased ingestive behaviors and increased walking, grooming, and rearing behaviors). A group of rats was injected intracerebrally either with a novel Accell™ SMARTpool TACE/ADAM17 siRNA or a corresponding siRNA vehicle (control). The RNAscope Multiplex Fluorescent v2 Assay was used to visualize mRNA expression. Automated puncta quantification and analyses demonstrated that TACE/ADAM17 siRNA administration reduced TACE/ADAM17 mRNA levels in the medial prefrontal cortex (59% reduction relative to control). We found that the rats that received prefrontal cortical TACE/ADAM17 siRNA administration exhibited altered eating patterns (e.g., increased food intake and time in the feeding zone during the light cycle).

CONCLUSION

This study supports that the prefrontal cortex is sensitive to adolescent chronic stress and suggests that TACE/ADAM17 may be involved in the brain responses to stress.

Evaluation of 6-PPD quinone toxicity on lung of male BALB/c mice by quantitative proteomics

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6-PPDQ), a transformation product of tyre-derived 6-PPD, has been frequently detected in different environments. After 6-PPDQ exposure, we here aimed to examine dynamic lung bioaccumulation, lung injury, and the underlying molecular basis in male BALB/c mice. After single injection at concentration of 4 mg/kg, 6-PPDQ remained in lung up to day 28, and higher level of 6-PPDQ bioaccumulation in lung was observed after repeated injection. Severe inflammation was observed in lung after both single and repeated 6-PPDQ injection as indicated by changes of inflammatory cytokines (TNF-α, IL-6 and IL-10). Sirius red staining and hydroxyproline content analysis indicated that repeated rather than single 6-PPDQ injection induced fibrosis in lung. Repeated 6-PPDQ injection also severely impaired lung function in mice by influencing chord compliance (Cchord) and enhanced pause (Penh). Proteomes analysis was further carried out to identify molecular targets of 6-PPDQ after repeated injection, which was confirmed by transcriptional expression analysis and immunohistochemistry staining. Alterations in Ripk1, Fadd, Il-6st, and Il-16 expressions were identified to be associated with inflammation induction of lung after repeated 6-PPDQ injection. Alteration in Smad2 expression was identified to be associated with fibrosis formation in lung of 6-PPDQ exposed mice. Therefore, long-term and repeated 6-PPDQ exposure potentially resulted in inflammation and fibrosis in lung by affecting certain molecular signals in mammals. Our results suggested several aspects of lung injury caused by 6-PPDQ and provide the underlying molecular basis. These observations implied the possible risks of long-term 6-PPDQ exposure to human health.

Transcriptional dynamics and regulatory function of milRNAs in Ascosphaera apis invading Apis mellifera larvae

In the present study, small RNA (sRNA) data from Ascosphaera apis were filtered from sRNA-seq datasets from the gut tissues of A. apis-infected Apis mellifera ligustica worker larvae, which were combined with the previously gained sRNA-seq data from A. apis spores to screen differentially expressed milRNAs (DEmilRNAs), followed by trend analysis and investigation of the DEmilRNAs in relation to significant trends. Additionally, the interactions between the DEmilRNAs and their target mRNAs were verified using a dual-luciferase reporter assay. In total, 974 A. apis milRNAs were identified. The first base of these milRNAs was biased toward U. The expression of six milRNAs was confirmed by stem-loop RT-PCR, and the sequences of milR-3245-y and milR-10285-y were validated using Sanger sequencing. These miRNAs grouped into four significant trends, with the target mRNAs of DEmilRNAs involving 42 GO terms and 120 KEGG pathways, such as the fungal-type cell wall and biosynthesis of secondary metabolites. Further investigation demonstrated that 299 DEmilRNAs (novel-m0011-3p, milR-10048-y, bantam-y, etc.) potentially targeted nine genes encoding secondary metabolite-associated enzymes, while 258 (milR-25-y, milR-14-y, milR-932-x, etc.) and 419 (milR-4561-y, milR-10125-y, let-7-x, etc.) DEmilRNAs putatively targeted virulence factor-encoded genes and nine genes involved in the MAPK signaling pathway, respectively. Additionally, the interaction between ADM-B and milR-6882-x, as well as between PKIA and milR-7009-x were verified. Together, these results not only offer a basis for clarifying the mechanisms underlying DEmilRNA-regulated pathogenesis of A. apis and a novel insight into the interaction between A. apis and honey bee larvae, but also provide candidate DEmilRNA-gene axis for further investigation.

iRhom2 regulates ectodomain shedding and surface expression of the major histocompatibility complex (MHC) class I

Proteolytic release of transmembrane proteins from the cell surface, the so called ectodomain shedding, is a key process in inflammation. Inactive rhomboid 2 (iRhom2) plays a crucial role in this context, in that it guides maturation and function of the sheddase ADAM17 (a disintegrin and metalloproteinase 17) in immune cells, and, ultimately, its ability to release inflammatory mediators such as tumor necrosis factor α (TNFα). Yet, the macrophage sheddome of iRhom2/ADAM17, which is the collection of substrates that are released by the proteolytic complex, is only partly known. In this study, we applied high-resolution proteomics to murine and human iRhom2-deficient macrophages for a systematic identification of substrates, and therefore functions, of the iRhom2/ADAM17 proteolytic complex. We found that iRhom2 loss suppressed the release of a group of transmembrane proteins, including known (e.g. CSF1R) and putative novel ADAM17 substrates. In the latter group, shedding of major histocompatibility complex class I molecules (MHC-I) was consistently reduced in both murine and human macrophages when iRhom2 was ablated. Intriguingly, it emerged that in addition to its shedding, iRhom2 could also control surface expression of MHC-I by an undefined mechanism. We have demonstrated the biological significance of this process by using an in vitro model of CD8+ T-cell (CTL) activation. In this model, iRhom2 loss and consequent reduction of MHC-I expression on the cell surface of an Epstein-Barr virus (EBV)-transformed lymphoblastoid cell line dampened activation of autologous CTLs and their cell-mediated cytotoxicity. Taken together, this study uncovers a new role for iRhom2 in controlling cell surface levels of MHC-I by a dual mechanism that involves regulation of their surface expression and ectodomain shedding.

Epitranscriptomics m6A analyses reveal distinct m6A marks under tumor necrosis factor α (TNF-α)-induced apoptotic conditions in HeLa cells

Tumor necrosis factor-α (TNF-α) is a ligand that induces both intrinsic and extrinsic apoptotic pathways in HeLa cells by modulating complex gene regulatory mechanisms. However, the full spectrum of TNF-α-modulated epitranscriptomic m6A marks is unknown. We employed a genomewide approach to examine the extent of m6A RNA modifications under TNF-α-modulated apoptotic conditions in HeLa cells. miCLIP-seq analyses revealed a plethora of m6A marks on 632 target mRNAs with an enrichment on 99 mRNAs associated with apoptosis. Interestingly, the m6A RNA modification patterns were quite different under cisplatin- and TNF-α-mediated apoptotic conditions. We then examined the abundance and translational efficiencies of several mRNAs under METTL3 knockdown and/or TNF-α treatment conditions. Our analyses showed changes in the translational efficiency of TP53INP1 mRNA based on the polysome profile analyses. Additionally, TP53INP1 protein amount was modulated by METTL3 knockdown upon TNF-α treatment but not CP treatment, suggesting the existence of a pathway-specific METTL3-TP53INP1 axis. Congruently, METLL3 knockdown sensitized HeLa cells to TNF-α-mediated apoptosis, which was also validated in a zebrafish larval xenograft model. These results suggest that apoptotic pathway-specific m6A methylation marks exist in cells and TNF-α-METTL3-TP53INP1 axis modulates TNF-α-mediated apoptosis in HeLa cells.

Development of gold nanocluster complex for the detection of tumor necrosis factor-alpha based on immunoassay

Tumor necrosis factor-alpha, TNF-α, a cytokine recognized as a key regulator of inflammatory responses, is primarily produced by activated monocytes and macrophages. Measuring TNF-α levels serves as a valuable indicator for tracking several diseases and pathological states. Gold nanotechnology has been identified as a highly effective catalyst with unique properties for measuring inflammatory cytokines. This study aimed to synthesize gold nanoclusters (AuNCs) and the AuNCs-streptavidin system, along with their characterizations and spherical morphology. The detection of TNF-α antigen with AuNCs was determined, and a new immunoassay-based AuNCs analytical platform was studied. In this study, it was demonstrated that the synthesized AuNCs and AuNCs-streptavidin showed a bright-yellow appearance with absorption peaks at A600 and A610 nm, respectively. The approximately spherical shape was observed by TEM analysis. The AuNCs demonstrated a sensitivity limit for the detection of the TNF-α antigen, with a linear dose-dependent detection range of less than 1.25 ng/mL. The products of the band sizes and band intensities were proportional to the amount of TNF-α in the range of ∼80 kDa, ∼55 kDa, and ∼ 25 kDa in western blot analysis. The TNF-α in cell lysate was successfully detected using an immunoassay after the activation of RAW264.7 cells with lipopolysaccharide (LPS). This assay may serve as a viable alternative for TNF-α detection with high speed, sensitivity, and qualities, ensuring its broad applications.

Photoaffinity labeling coupled with proteomics identify PDI-ADAM17 module is targeted by (-)-vinigrol to induce TNFR1 shedding and ameliorate rheumatoid arthritis in mice

Various biological agents have been developed to target tumor necrosis factor alpha (TNF-α) and its receptor TNFR1 for the rheumatoid arthritis (RA) treatment, whereas small molecules modulating such cytokine receptors are rarely reported in comparison to the biologicals. Here, by revealing the mechanism of action of vinigrol, a diterpenoid natural product, we show that inhibition of the protein disulfide isomerase (PDI, PDIA1) by small molecules activates A disintegrin and metalloprotease 17 (ADAM17) and then leads to the TNFR1 shedding on mouse and human cell membranes. This small-molecule-induced receptor shedding not only effectively blocks the inflammatory response caused by TNF-α in cells, but also reduces the arthritic score and joint damage in the collagen-induced arthritis mouse model. Our study indicates that targeting the PDI-ADAM17 signaling module to regulate the shedding of cytokine receptors by the chemical approach constitutes a promising strategy for alleviating RA.

Immune cell-derived signals governing epithelial phenotypes in homeostasis and inflammation

The intestinal epithelium fulfills important physiological functions and forms a physical barrier to the intestinal lumen. Barrier function is regulated by several pathways, and its impairment contributes to the pathogenesis of inflammatory bowel disease (IBD), a chronic inflammatory condition affecting more than seven million people worldwide. Current treatment options specifically target inflammatory mediators and have led to improvement of clinical outcomes; however, a significant proportion of patients experience treatment failure. Pro-repair effects of inflammatory mediators on the epithelium are emerging. In this review we summarize current knowledge on involved epithelial pathways, identify open questions, and put recent findings into clinical perspective, and pro-repair effects. A detailed understanding of epithelial pathways integrating mucosal stimuli in homeostasis and inflammation is crucial for the development of novel, more targeted therapies.

Pathological mutations reveal the key role of the cytosolic iRhom2 N-terminus for phosphorylation-independent 14-3-3 interaction and ADAM17 binding, stability, and activity

The protease ADAM17 plays an important role in inflammation and cancer and is regulated by iRhom2. Mutations in the cytosolic N-terminus of human iRhom2 cause tylosis with oesophageal cancer (TOC). In mice, partial deletion of the N-terminus results in a curly hair phenotype (cub). These pathological consequences are consistent with our findings that iRhom2 is highly expressed in keratinocytes and in oesophageal cancer. Cub and TOC are associated with hyperactivation of ADAM17-dependent EGFR signalling. However, the underlying molecular mechanisms are not understood. We have identified a non-canonical, phosphorylation-independent 14-3-3 interaction site that encompasses all known TOC mutations. Disruption of this site dysregulates ADAM17 activity. The larger cub deletion also includes the TOC site and thus also dysregulated ADAM17 activity. The cub deletion, but not the TOC mutation, also causes severe reductions in stimulated shedding, binding, and stability of ADAM17, demonstrating the presence of additional regulatory sites in the N-terminus of iRhom2. Overall, this study contrasts the TOC and cub mutations, illustrates their different molecular consequences, and reveals important key functions of the iRhom2 N-terminus in regulating ADAM17.

New insight into the role of the ADAM protease family in breast carcinoma progression

Protease and adhesion molecules play a very emphasized role in the occurrence or progression of metastasis in many types of cancers. In this context, a molecule that contains both protease and adhesion functions play a crucial role in metastasis. ADAMs (a disintegrin and metalloprotease) are molecules with this special characteristic. Recently, a lot of attention has been attracted to various ADAM molecules and researchers have tried to elucidate the role of ADAMs in breast cancer occurrence and progression. Disrupting ADAMs protease and adhesion capabilities can lead to the discovery of worthy therapeutic targets in breast cancer treatment. In this review, we intend to discuss the mechanism of action of various ADAM molecules, their relation to pathogenic processes of breast cancer, and their potential as possible targets for breast cancer treatment.

Listen to Your Gut: Key Concepts for Bioengineering Advanced Models of the Intestine

The intestine performs functions central to human health by breaking down food and absorbing nutrients while maintaining a selective barrier against the intestinal microbiome. Key to this barrier function are the combined efforts of lumen-lining specialized intestinal epithelial cells, and the supportive underlying immune cell-rich stromal tissue. The discovery that the intestinal epithelium can be reproduced in vitro as intestinal organoids introduced a new way to understand intestinal development, homeostasis, and disease. However, organoids reflect the intestinal epithelium in isolation whereas the underlying tissue also contains myriad cell types and impressive chemical and structural complexity. This review dissects the cellular and matrix components of the intestine and discusses strategies to replicate them in vitro using principles drawing from bottom-up biological self-organization and top-down bioengineering. It also covers the cellular, biochemical and biophysical features of the intestinal microenvironment and how these can be replicated in vitro by combining strategies from organoid biology with materials science. Particularly accessible chemistries that mimic the native extracellular matrix are discussed, and bioengineering approaches that aim to overcome limitations in modelling the intestine are critically evaluated. Finally, the review considers how further advances may extend the applications of intestinal models and their suitability for clinical therapies.