A tissue injury sensing and repair pathway distinct from host pathogen defense

Novel heterologously expressed protein, AjPSPLP-3, derived from Apostichopus japonicus exhibits cell proliferation and migration activities

Developing more effective bioactive ingredients of natural origin is imperative for promoting wound healing. Sea cucumbers have long enjoyed a good reputation as both food delicacies and traditional medicines. In this study, we heterogeneously expressed a Apostichopus japonicus derived novel protein AjPSPLP-3, which exhibits a theoretical molecular weight of 13.034 kDa, through fusion with maltose binding protein (MBP). AjPSPLP-3 contains a strict CXXCXC motif, nine extremely conserved cysteine residues and two highly conserved cysteine residues. The predicted structure of AjPSPLP-3 consists of random coil and nine β-sheets, Cys30-Cys67, Cys38-Cys58, Cys53-Cys90, Cys56-Cys66, and Cys81-Cys102 participating in the formation of five pairs of disulfide bonds. In vitro experiments conducted on HaCaT cells proved that AjPSPLP-3 and MBP-fused AjPSPLP-3 significantly contribute to HaCaT cells proliferation and migration without exhibiting hemolytic activity on murine erythrocytes. Specifically, treatment with 10 μmol/L MBP-fused AjPSPLP-3 protein increased the viability of HaCaT cells by 12.28 % (p < 0.001), while treatment with 10 μmol/L AjPSPLP-3 protein increased viability of HaCaT cells by 6.01 % (p < 0.01). Furthermore, wound closure of MBP-fused AjPSPLP-3 and AjPSPLP-3 were 22.51 % (p < 0.01) and 7.32 % (p < 0.05) higher than that of the control groups in HaCaT cells following 24 h of incubation.

Epidermal Stem Cells: Interplay with the Skin Microenvironment During Wound Healing

Skin undergoes everyday turnover while often challenged by injuries. The wound healing process in the skin is a dynamic sequence of events that involves various cell types and signaling pathways. Epidermal stem cells (EpdSCs), the tissue-resident stem cells in the skin tissue, are in the center of this complicated process due to their special ability to self-renew and differentiate. During this process, EpdSCs interact actively with the tissue microenvironment, which is essential for proper re-epithelialization and skin barrier restoration. This review describes the intricate interplays between EpdSCs and various components of their surroundings, including ECM/fibroblasts, vasculature/endothelial cells, and immune cells, as well as their roles in tissue repair.

A hydrogen generator composed of poly (lactic-co-glycolic acid) nanofibre membrane loaded iron nanoparticles for infectious diabetic wound repair

Diabetic wound, which is chronic skin disease, poses a significant challenge in clinical practice because of persistent inflammation and impaired angiogenesis. Recently, hydrogen has emerged as a novel therapeutic agent due to its superior antioxidant and anti-inflammatory properties. In this study, we engineered a poly (lactic-co-glycolic acid) (PLGA) electrospun nanofibre membrane loaded with citric acid (CA) and iron (Fe) nanoparticles, referred to as Fe@PLGA + CA. Our in vitro assays demonstrated that the Fe@PLGA + CA membrane continuously generated and released hydrogen molecules via a chemical reaction between Fe and CA in an acidic microenvironment created by CA. We also discovered that hydrogen can ameliorate fibroblast migration disorders by reducing the levels of matrix metalloproteinase 9 (MMP9). Furthermore, we confirmed that hydrogen can scavenge or biochemically neutralise accumulated reactive oxygen species (ROS), inhibit pro-inflammatory responses, and induce anti-inflammatory reactions. This, in turn, promotes vessel formation, wound-healing and accelerates skin regeneration. These findings open new possibilities for using elemental iron in skin dressings and bring us one step closer to implementing hydrogen-releasing biomedical materials in clinical practice.

Schwann cell-secreted frizzled-related protein 1 dictates neuroinflammation and peripheral nerve degeneration after neurotrauma

Neurotrauma in limbs can induce sustained neuroinflammation, resulting in persistent disruption of nerve tissue architecture and retardation of axon regrowth. Despite macrophage-mediated inflammation promoting the removal of necrotic neural components and stimulating neo-vessel ingrowth, detrimental shifts in macrophage phenotype exacerbate nerve degeneration. Herein, we find that peripheral nerve injuries (PNIs) result in abundant secreted frizzled-related protein 1 (sFRP1) expression, particularly by Schwann cells (SCs). Heat shock protein 90 (HSP90) in macrophages recognizes sFRP1 and triggers a dysregulated secretion of inflammatory mediators. Single-cell atlas of human injured peripheral nerves reveals the appearance of sFRP1-expressing SCs with mesenchymal traits and macrophages with a proinflammatory genetic profile. Deletion of either SC-specific sFRP1 or macrophage-specific HSP90 alleviates neuroinflammation and prevents the progression of nerve degeneration. Together, our findings implicate the response of macrophages to SC-derived sFRP1 in exacerbating nerve damage following PNIs.

Intralesional gene expression profile of JAK-STAT signaling pathway and associated cytokines in Leishmania tropica-infected patients

Background

The JAK-STAT signaling pathway is a central cascade of signal transduction for the myriad of cytokines in which dysregulation has been implicated in progression of inflammatory and infectious diseases. However, the involvement of this pathway in human cutaneous leishmaniasis (CL) due to Leishmania (L.) tropica warrants further investigation.

Methods

This study sought to investigate differential gene expression of several cytokines and their associated jak-stat genes in the lesions of L. tropica-infected patients byquantitative Real-Time PCR. Further, the expression of five inhibitory immune checkpoint genes was evaluated.

Results

Results showed that the gene expression levelsof both Th1 (ifng, il12, il23) and Th2 (il4, il10) types cytokines were increased in the lesion of studied patients. Further, elevated expression levels of il35, il21, il27 and il24 genes were detected in the lesions of CL patients. Notably, the expression of the majority of genes involved in JAK/STAT signaling pathway as well as checkpoint genes including pdl1, ctla4 and their corresponding receptors was increased.

Conclusion

Our finding revealed dysregulation of cytokines and related jak-stat genes in the lesion of CL patients. These results highlight the need for further exploration of the functional importance of these genes in the pathogenesis of, and immunity to, CL.

Stem cells tightly regulate dead cell clearance to maintain tissue fitness

Billions of cells are eliminated daily from our bodies1-4. Although macrophages and dendritic cells are dedicated to migrating and engulfing dying cells and debris, many epithelial and mesenchymal tissue cells can digest nearby apoptotic corpses1-4. How these non-motile, non-professional phagocytes sense and eliminate dying cells while maintaining their normal tissue functions is unclear. Here we explore the mechanisms that underlie their multifunctionality by exploiting the cyclical bouts of tissue regeneration and degeneration during hair cycling. We show that hair follicle stem cells transiently unleash phagocytosis at the correct time and place through local molecular triggers that depend on both lipids released by neighbouring apoptotic corpses and retinoids released by healthy counterparts. We trace the heart of this dual ligand requirement to RARγ-RXRα, whose activation enables tight regulation of apoptotic cell clearance genes and provides an effective, tunable mechanism to offset phagocytic duties against the primary stem cell function of preserving tissue integrity during homeostasis. Finally, we provide functional evidence that hair follicle stem cell-mediated phagocytosis is not simply redundant with professional phagocytes but rather has clear benefits to tissue fitness. Our findings have broad implications for other non-motile tissue stem or progenitor cells that encounter cell death in an immune-privileged niche.

Interleukin-24: A molecular mediator of particulate matter's impact on skin aging

Air pollution, a global health concern, has been associated with adverse effects on human health. In particular, particulate matter (PM), which is a major contributor to air pollution, impacts various organ systems including the skins. In fact, PM has been suggested as a culprit for accelerating skin aging and pigmentation. In this study, using single-cell RNA sequencing, IL-24 was found to be highly upregulated among the differentially expressed genes commonly altered in keratinocytes and fibroblasts of ex vivo skins exposed to PM. It was verified that PM exposure triggered the expression of IL-24 in keratinocytes, which subsequently led to a decrease in type I procollagen expression and an increase in MMP1 expression in fibroblasts. Furthermore, long-term treatment of IL-24 induced cellular senescence in fibroblasts. Through high-throughput screening, we identified chemical compounds that inhibit the IL-24-STAT3 signaling pathway, with lovastatin being the chosen candidate. Lovastatin not only effectively reduced the expression of IL24 induced by PM in keratinocytes but also exhibited a capacity to restore the decrease in type I procollagen and the increase in MMP1 caused by IL-24 in fibroblasts. This study provides insights into the significance of IL-24, illuminating mechanisms behind PM-induced skin aging, and proposes IL-24 as a promising target to mitigate PM-associated skin aging.

Novel insight into MDA-7/IL-24: A potent therapeutic target for autoimmune and inflammatory diseases

Melanoma differentiation-associated gene-7 (MDA-7)/interleukin-24 (IL-24) is a pleiotropic member of the IL-10 family of cytokines, and is involved in multiple biological processes, including cell proliferation, cell differentiation, tissue fibrosis, the inflammatory response, and antitumor activity. MDA-7/IL-24 can regulate epithelial integrity, homeostasis, mucosal immunity and host resistance to various pathogens by enhancing immune and inflammatory responses. Our recent study revealed the mechanism of MDA-7/IL-24 in promoting airway inflammation and airway remodeling through activating the JAK/STAT3 and ERK signaling pathways in bronchial epithelial cells. Herein, we summarize the cellular sources, inducers, target cells, signaling pathways, and biological effects of MDA-7/IL-24 in several allergic and autoimmune diseases. This review also synopsizes recent advances in clinical research targeting MDA-7/IL-24 or its receptors. Based on these advancements, we emphasize its potential as a target for immunotherapy and discuss the challenges of developing immunotherapeutic drugs targeting MDA-7/IL-24 or its receptors in autoimmune and inflammatory disorders.

Epidermal stem cells: skin surveillance and clinical perspective

The skin epidermis is continually influenced by a myriad of internal and external elements. At its basal layer reside epidermal stem cells, which fuels epidermal renovation and hair regeneration with powerful self-renewal ability, as well as keeping diverse signals that direct their activity under surveillance with quick response. The importance of epidermal stem cells in wound healing and immune-related skin conditions has been increasingly recognized, and their potential for clinical applications is attracting attention. In this review, we delve into recent advancements and the various physiological and psychological factors that govern distinct epidermal stem cell populations, including psychological stress, mechanical forces, chronic aging, and circadian rhythm, as well as providing an overview of current methodological approaches. Furthermore, we discuss the pathogenic role of epidermal stem cells in immune-related skin disorders and their potential clinical applications.

Structurally Oriented Carbon Dots as ROS Nanomodulators for Dynamic Chronic Inflammation and Infection Elimination

The selective elimination of cytotoxic ROS while retaining essential ones is pivotal in the management of chronic inflammation. Co-occurring bacterial infection further complicates the conditions, necessitating precision and an efficacious treatment strategy. Herein, the dynamic ROS nanomodulators are rationally constructed through regulating the surface states of herbal carbon dots (CDs) for on-demand inflammation or infection elimination. The phenolic OH containing CDs derived from honeysuckle (HOCD) and dandelion (DACD) demonstrated appropriate redox potentials, ensuring their ability to scavenge cytotoxic ROS such as ·OH and ONOO-, while invalidity toward essential ones such as O2·-, H2O2, and NO. This enables efficient treatment of chronic inflammation without affecting essential ROS signal pathways. The surface C-N/C═N of CDs derived from taxus leaves (TACD) and DACD renders them with suitable band structures, facilitating absorption in the red region and efficient generation of O2·- upon light irradiation for sterilization. Specifically, the facilely prepared DACD demonstrates fascinating dynamic ROS modulating ability, making it highly suitable for addressing concurrent chronic inflammation and infection, such as diabetic wound infection. This dynamic ROS regulation strategy facilitates the realization of the precise and efficient treatment of chronic inflammation and infection with minimal side effects, holding immense potential for clinical practice.

GelMA loaded with platelet lysate promotes skin regeneration and angiogenesis in pressure ulcers by activating STAT3

Pressure ulcers (PU) are caused by persistent long-term pressure, which compromises the integrity of the epidermis, dermis, and subcutaneous adipose tissue layer by layer, making it difficult to heal. Platelet products such as platelet lysate (PL) can promote tissue regeneration by secreting numerous growth factors based on clinical studies on skin wound healing. However, the components of PL are difficult to retain in wounds. Gelatin methacrylate (GelMA) is a photopolymerizable hydrogel that has lately emerged as a promising material for tissue engineering and regenerative medicine. The PL liquid was extracted, flow cytometrically detected for CD41a markers, and evenly dispersed in the GelMA hydrogel to produce a surplus growth factor hydrogel system (PL@GM). The microstructure of the hydrogel system was observed under a scanning electron microscope, and its sustained release efficiency and biological safety were tested in vitro. Cell viability and migration of human dermal fibroblasts, and tube formation assays of human umbilical vein endothelial cells were applied to evaluate the ability of PL to promote wound healing and regeneration in vitro. Real-time polymerase chain reaction (PCR) and western blot analyses were performed to elucidate the skin regeneration mechanism of PL. We verified PL's therapeutic effectiveness and histological analysis on the PU model. PL promoted cell viability, migration, wound healing and angiogenesis in vitro. Real-time PCR and western blot indicated PL suppressed inflammation and promoted collagen I synthesis by activating STAT3. PL@GM hydrogel system demonstrated optimal biocompatibility and favorable effects on essential cells for wound healing. PL@GM also significantly stimulated PU healing, skin regeneration, and the formation of subcutaneous collagen and blood vessels. PL@GM could accelerate PU healing by promoting fibroblasts to migrate and secrete collagen and endothelial cells to vascularize. PL@GM promises to be an effective and convenient treatment modality for PU, like chronic wound treatment.

The mechano-chemical circuit in fibroblasts and dendritic cells drives basal cell proliferation in psoriasis

Psoriasis is an intractable immune-mediated disorder that disrupts the skin barrier. While studies have dissected the mechanism by which immune cells directly regulate epidermal cell proliferation, the involvement of dermal fibroblasts in the progression of psoriasis remains unclear. Here, we identified that signals from dendritic cells (DCs) that migrate to the dermal-epidermal junction region enhance dermal stiffness by increasing extracellular matrix (ECM) expression, which further promotes basal epidermal cell hyperproliferation. We analyzed cell-cell interactions and observed stronger interactions between DCs and fibroblasts than between DCs and epidermal cells. Using single-cell RNA (scRNA) sequencing, spatial transcriptomics, immunostaining, and stiffness measurement, we found that DC-secreted LGALS9 can be received by CD44+ dermal fibroblasts, leading to increased ECM expression that creates a stiffer dermal environment. By employing mouse psoriasis and skin organoid models, we discovered a mechano-chemical signaling pathway that originates from DCs, extends to dermal fibroblasts, and ultimately enhances basal cell proliferation in psoriatic skin.

Inhibitory effect of human interleukin-24 on the proliferation, migration, and invasion of cervical cancer cells

OBJECTIVE

This study aimed to identify significantly differentially expressed genes (DEGs) related to cervical cancer by exploring extensive gene expression datasets to unveil new therapeutic targets.

METHODS

Gene expression profiles were extracted from the Gene Expression Omnibus, The Cancer Genome Atlas, and the Genotype-Tissue Expression platforms. A differential expression analysis identified DEGs in cervical cancer cases. Weighted gene co-expression network analysis (WGCNA) was implemented to locate genes closely linked to the clinical traits of diseases. Machine learning algorithms, including LASSO regression and the random forest algorithm, were applied to pinpoint key genes.

RESULTS

The investigation successfully isolated DEGs pertinent to cervical cancer. Interleukin-24 was recognized as a pivotal gene via WGCNA and machine learning techniques. Experimental validations demonstrated that human interleukin (hIL)-24 inhibited proliferation, migration, and invasion, while promoting apoptosis, in SiHa and HeLa cervical cancer cells, affirming its role as a therapeutic target.

CONCLUSION

The multi-database analysis strategy employed herein emphasized hIL-24 as a principal gene in cervical cancer pathogenesis. The findings suggest hIL-24 as a promising candidate for targeted therapy, offering a potential avenue for innovative treatment modalities. This study enhances the understanding of molecular mechanisms of cervical cancer and aids in the pursuit of novel oncological therapies.

The single cell immunogenomic landscape after neoadjuvant immunotherapy combined chemotherapy in esophageal squamous cell carcinoma

Neoadjuvant immunotherapy represents promising strategy in the treatment of esophageal squamous cell carcinoma (ESCC). However, the mechanisms underlying its impact on treatment sensitivity or resistance remain a subject of controversy. In this study, we conducted single-cell RNA and T/B cell receptor (scTCR/scBCR) sequencing of CD45+ immune cells on samples from 10 patients who received neoadjuvant immunotherapy and chemotherapy. We also validated our findings using multiplexed immunofluorescence and analyzed bulk RNA-seq from other cohorts in public database. By integrating analysis of 87357 CD45+ cells, we found GZMK + effector memory T cells (Tem) were relatively enriched and CXCL13+ exhausted T cells (Tex) and regulator T cells (Treg) decreased among responders, indicating a persistent anti-tumor memory process. Additionally, the enhanced presence of BCR expansion and somatic hypermutation process within TNFRSF13B + memory B cells (Bmem) suggested their roles in antigen presentation. This was further corroborated by the evidence of the T-B co-stimulation pattern and CXCL13-CXCR5 axis. The complexity of myeloid cell heterogeneity was also particularly pronounced. The elevated expression of S100A7 in ESCC, as detected by bulk RNA-seq, was associated with an exhausted and immunosuppressive tumor microenvironment. In summary, this study has unveiled a potential regulatory network among immune cells and the clonal dynamics of their functions, and the mechanisms of exhaustion and memory conversion between GZMK + Tem and TNFRSF13B + Bmem from antigen presentation and co-stimulation perspectives during neoadjuvant PD-1 blockade treatment in ESCC.

Alcaligenes faecalis corrects aberrant matrix metalloproteinase expression to promote reepithelialization of diabetic wounds

Chronic wounds are a common and costly complication of diabetes, where multifactorial defects contribute to dysregulated skin repair, inflammation, tissue damage, and infection. We previously showed that aspects of the diabetic foot ulcer microbiota were correlated with poor healing outcomes, but many microbial species recovered remain uninvestigated with respect to wound healing. Here, we focused on Alcaligenes faecalis, a Gram-negative bacterium that is frequently recovered from chronic wounds but rarely causes infection. Treatment of diabetic wounds with A. faecalis accelerated healing during early stages. We investigated the underlying mechanisms and found that A. faecalis treatment promotes reepithelialization of diabetic keratinocytes, a process that is necessary for healing but deficient in chronic wounds. Overexpression of matrix metalloproteinases in diabetes contributes to failed epithelialization, and we found that A. faecalis treatment balances this overexpression to allow proper healing. This work uncovers a mechanism of bacterial-driven wound repair and provides a foundation for the development of microbiota-based wound interventions.

CD80 on skin stem cells promotes local expansion of regulatory T cells upon injury to orchestrate repair within an inflammatory environment

Following tissue damage, epithelial stem cells (SCs) are mobilized to enter the wound, where they confront harsh inflammatory environments that can impede their ability to repair the injury. Here, we investigated the mechanisms that protect skin SCs within this inflammatory environment. Characterization of gene expression profiles of hair follicle SCs (HFSCs) that migrated into the wound site revealed activation of an immune-modulatory program, including expression of CD80, major histocompatibility complex class II (MHCII), and CXC motif chemokine ligand 5 (CXCL5). Deletion of CD80 in HFSCs impaired re-epithelialization, reduced accumulation of peripherally generated Treg (pTreg) cells, and increased infiltration of neutrophils in wounded skin. Importantly, similar wound healing defects were also observed in mice lacking pTreg cells. Our findings suggest that upon skin injury, HFSCs establish a temporary protective network by promoting local expansion of Treg cells, thereby enabling re-epithelialization while still kindling inflammation outside this niche until the barrier is restored.

Systematic dissection of tumor-normal single-cell ecosystems across a thousand tumors of 30 cancer types

The complexity of the tumor microenvironment poses significant challenges in cancer therapy. Here, to comprehensively investigate the tumor-normal ecosystems, we perform an integrative analysis of 4.9 million single-cell transcriptomes from 1070 tumor and 493 normal samples in combination with pan-cancer 137 spatial transcriptomics, 8887 TCGA, and 1261 checkpoint inhibitor-treated bulk tumors. We define a myriad of cell states constituting the tumor-normal ecosystems and also identify hallmark gene signatures across different cell types and organs. Our atlas characterizes distinctions between inflammatory fibroblasts marked by AKR1C1 or WNT5A in terms of cellular interactions and spatial co-localization patterns. Co-occurrence analysis reveals interferon-enriched community states including tertiary lymphoid structure (TLS) components, which exhibit differential rewiring between tumor, adjacent normal, and healthy normal tissues. The favorable response of interferon-enriched community states to immunotherapy is validated using immunotherapy-treated cancers (n = 1261) including our lung cancer cohort (n = 497). Deconvolution of spatial transcriptomes discriminates TLS-enriched from non-enriched cell types among immunotherapy-favorable components. Our systematic dissection of tumor-normal ecosystems provides a deeper understanding of inter- and intra-tumoral heterogeneity.

Quantitative Assessment of Intracellular Effectors and Cellular Response in RAGE Activation

The review delves into the methods for the quantitative assessment of intracellular effectors and cellular response of Receptor for Advanced Glycation End products (RAGE), a vital transmembrane receptor involved in a range of physiological and pathological processes. RAGE bind to Advanced Glycation End products (AGEs) and other ligands, which in turn activate diverse downstream signaling pathways that impact cellular responses such as inflammation, oxidative stress, and immune reactions. The review article discusses the intracellular signaling pathways activated by RAGE followed by differential activation of RAGE signaling across various diseases. This will ultimately guide researchers in developing targeted and effective interventions for diseases associated with RAGE activation. Further, we have discussed how PCR, western blotting, and microscopic examination of various molecules involved in downstream signaling can be leveraged to monitor, diagnose, and explore diseases involving proteins with unique post-translational modifications. This review article underscores the pressing need for advancements in molecular approaches for disease detection and management involving RAGE.

Vaccine Strategies to Elicit Mucosal Immunity

Vaccines are essential tools to prevent infection and control transmission of infectious diseases that threaten public health. Most infectious agents enter their hosts across mucosal surfaces, which make up key first lines of host defense against pathogens. Mucosal immune responses play critical roles in host immune defense to provide durable and better recall responses. Substantial attention has been focused on developing effective mucosal vaccines to elicit robust localized and systemic immune responses by administration via mucosal routes. Mucosal vaccines that elicit effective immune responses yield protection superior to parenterally delivered vaccines. Beyond their valuable immunogenicity, mucosal vaccines can be less expensive and easier to administer without a need for injection materials and more highly trained personnel. However, developing effective mucosal vaccines faces many challenges, and much effort has been directed at their development. In this article, we review the history of mucosal vaccine development and present an overview of mucosal compartment biology and the roles that mucosal immunity plays in defending against infection, knowledge that has helped inform mucosal vaccine development. We explore new progress in mucosal vaccine design and optimization and novel approaches created to improve the efficacy and safety of mucosal vaccines.

The dichotomic role of single cytokines: Fine-tuning immune responses

Cytokines are known for their pleiotropic effects. They can be classified by their function as pro-inflammatory, such as tumor necrosis factor (TNF), interleukin (IL) 1 and IL-12, or anti-inflammatory, like IL-10, IL-35 and transforming growth factor β (TGF-β). Though this type of classification is an important simplification for the understanding of the general cytokine's role, it can be misleading. Here, we discuss recent studies that show a dichotomic role of the so-called pro and anti-inflammatory cytokines, highlighting that their function can be dependent on the microenvironment and their concentrations. Furthermore, we discuss how the back-and-forth interplay between cytokines and immunometabolism can influence the dichotomic role of inflammatory responses as an important target to complement cytokine-based therapies.

Recent Advancement in Novel Wound Healing Therapies by Using Antimicrobial Peptides Derived from Humans and Amphibians

The skin is the biggest organ in the human body. It is the first line of protection against invading pathogens and the starting point for the immune system. The focus of this review is on the use of amphibian-derived peptides and antimicrobial peptides (AMPs) in the treatment of wound healing. When skin is injured, a chain reaction begins that includes inflammation, the formation of new tissue, and remodelling of existing tissue to aid in the healing process. Collaborating with non-immune cells, resident and recruited immune cells in the skin remove foreign invaders and debris, then direct the repair and regeneration of injured host tissues. Restoration of normal structure and function requires the healing of damaged tissues. However, a major issue that slows wound healing is infection. AMPs are just one type of host-defense chemicals that have developed in multicellular animals to regulate the immune response and limit microbial proliferation in response to various types of biological or physical stress. Therefore, peptides isolated from amphibians represent novel therapeutic tools and approaches for regenerating damaged skin. Peptides that speed up the healing process could be used as therapeutic lead molecules in future research into novel drugs. AMPs and amphibian-derived peptides may be endogenous mediators of wound healing and treat non-life-threatening skin and epithelial lesions. Thus, the present article was drafted with to incorporate different peptides used in wound healing, their method of preparation and routes of administration.

Development and Prospective Applications of 3D Membranes as a Sensor for Monitoring and Inducing Tissue Regeneration

For decades, tissue regeneration has been a challenging issue in scientific modeling and human practices. Although many conventional therapies are already used to treat burns, muscle injuries, bone defects, and hair follicle injuries, there remains an urgent need for better healing effects in skin, bone, and other unique tissues. Recent advances in three-dimensional (3D) printing and real-time monitoring technologies have enabled the creation of tissue-like membranes and the provision of an appropriate microenvironment. Using tissue engineering methods incorporating 3D printing technologies and biomaterials for the extracellular matrix (ECM) containing scaffolds can be used to construct a precisely distributed artificial membrane. Moreover, advances in smart sensors have facilitated the development of tissue regeneration. Various smart sensors may monitor the recovery of the wound process in different aspects, and some may spontaneously give feedback to the wound sites by releasing biological factors. The combination of the detection of smart sensors and individualized membrane design in the healing process shows enormous potential for wound dressings. Here, we provide an overview of the advantages of 3D printing and conventional therapies in tissue engineering. We also shed light on different types of 3D printing technology, biomaterials, and sensors to describe effective methods for use in skin and other tissue regeneration, highlighting their strengths and limitations. Finally, we highlight the value of 3D bioengineered membranes in various fields, including the modeling of disease, organ-on-a-chip, and drug development.

The driving mechanism and targeting value of mimicry between vascular endothelial cells and tumor cells in tumor progression

The difficulty and poor prognosis of malignant tumor have always been a difficult problem to be solved. The internal components of solid tumor are complex, including tumor cells, stromal cells and immune cells, which play an important role in tumor proliferation, migration, metastasis and drug resistance. Hence, targeting of only the tumor cells will not likely improve survival. Various studies have reported that tumor cells and endothelial cells have high plasticity, which is reflected in the fact that they can simulate each other's characteristics by endothelial-mesenchymal transition (EndMT) and vasculogenic mimicry (VM). In this paper, this mutual mimicry concept was integrated and reviewed for the first time, and their similarities and implications for tumor development are discussed. At the same time, possible therapeutic methods are proposed to provide new directions and ideas for clinical targeted therapy and immunotherapy of tumor.

STING regulates the transformation of the proinflammatory macrophage phenotype by HIF1A into autoimmune myocarditis

Macrophages play an essential role in the pathogenesis of autoimmune myocarditis, but the molecular mechanism remains largely unknown. Here, the role of Stimulator of interferon gene (Sting) in autoimmune myocarditis was investigated. Six-week-old male BALB/c mice received two subcutaneous injections of 250 μg α-MyHC peptide to establish experimental autoimmune myocarditis (EAM). With single-cell RNA sequencing analysis of cardiac immune (Cd45+) cells, Sting was found to initiate proinflammatory macrophage differentiation related to the acute EAM phase. Furthermore, proinflammatory macrophages contribute to the pathogenesis of EAM via hypoxia-inducible factor-1α (Hif1α). A higher expression level of Sting was detected in macrophages from myocarditis, which was positively correlated with Hif1α expression. Single-stranded DNA (ssDNA) accumulation in macrophages in myocarditis was observed in the hearts of EAM mice. Pharmacological blockade of STING by C-176 (a specific inhibitor) ameliorated the inflammatory response of EAM and reduced proinflammatory molecule (Ifn-β, Tnf-α, Ccl2, and F4/80) expression and Hif1α expression. In vitro studies revealed that ssDNA activated the expression of Sting; in turn, Sting accelerated proinflammatory molecule expression in mouse macrophages. Inhibition of Hif1α expression could reduce Sting-associated cardiac inflammation and proinflammatory molecule expression. In addition, the expression of STING and ssDNA accumulation in macrophages were observed in human autoimmune myocarditis heart samples. STING activated proinflammatory macrophage via HIF1A, promoting the development of autoimmune myocarditis. The STING signaling pathway might provide a novel mechanism of autoimmune myocarditis and serve as a potential therapeutic target for autoimmune myocarditis patients.

Regulation of IL-24/IL-20R2 complex formation using photocaged tyrosines and UV light

Human interleukin 24 (IL-24) is a multifunctional cytokine that represents an important target for autoimmune diseases and cancer. Since the biological functions of IL-24 depend on interactions with membrane receptors, on-demand regulation of the affinity between IL-24 and its cognate partners offers exciting possibilities in basic research and may have applications in therapy. As a proof-of-concept, we developed a strategy based on recombinant soluble protein variants and genetic code expansion technology to photocontrol the binding between IL-24 and one of its receptors, IL-20R2. Screening of non-canonical ortho-nitrobenzyl-tyrosine (NBY) residues introduced at several positions in both partners was done by a combination of biophysical and cell signaling assays. We identified one position for installing NBY, tyrosine70 of IL-20R2, which results in clear impairment of heterocomplex assembly in the dark. Irradiation with 365-nm light leads to decaging and reconstitutes the native tyrosine of the receptor that can then associate with IL-24. Photocaged IL-20R2 may be useful for the spatiotemporal control of the JAK/STAT phosphorylation cascade.

The mTOR signalling in corneal diseases: A recent update

Corneal diseases affect 4.2 million people worldwide and are a leading cause of vision impairment and blindness. Current treatments for corneal diseases, such as antibiotics, steroids, and surgical interventions, have numerous disadvantages and challenges. Thus, there is an urgent need for more effective therapies. Although the pathogenesis of corneal diseases is not fully understood, it is known that injury caused by various stresses and postinjury healing, such as epithelial renewal, inflammation, stromal fibrosis, and neovascularization, are highly involved. Mammalian target of rapamycin (mTOR) is a key regulator of cell growth, metabolism, and the immune response. Recent studies have revealed that activation of mTOR signalling extensively contributes to the pathogenesis of various corneal diseases, and inhibition of mTOR with rapamycin achieves promising outcomes, supporting the potential of mTOR as a therapeutic target. In this review, we detail the function of mTOR in corneal diseases and how these characteristics contribute to disease treatment using mTOR-targeted drugs.

Wound microbiota-mediated correction of matrix metalloproteinase expression promotes re-epithelialization of diabetic wounds

Chronic wounds are a common and costly complication of diabetes, where multifactorial defects contribute to dysregulated skin repair, inflammation, tissue damage, and infection. We previously showed that aspects of the diabetic foot ulcer microbiota were correlated with poor healing outcomes, but many microbial species recovered remain uninvestigated with respect to wound healing. Here we focused on Alcaligenes faecalis , a Gram-negative bacterium that is frequently recovered from chronic wounds but rarely causes infection. Treatment of diabetic wounds with A. faecalis accelerated healing during early stages. We investigated the underlying mechanisms and found that A. faecalis treatment promotes re-epithelialization of diabetic keratinocytes, a process which is necessary for healing but deficient in chronic wounds. Overexpression of matrix metalloproteinases in diabetes contributes to failed epithelialization, and we found that A. faecalis treatment balances this overexpression to allow proper healing. This work uncovers a mechanism of bacterial-driven wound repair and provides a foundation for the development of microbiota-based wound interventions.

Interleukin 24: Signal Transduction Pathways

Interleukin 24 is a member of the IL-10 family with crucial roles in antitumor, wound healing responses, host defense, immune regulation, and inflammation. Interleukin 24 is produced by both immune and nonimmune cells. Its canonical pathway relies on recognition and interaction with specific Interleukin 20 receptors in the plasma membrane and subsequent cytoplasmic Janus protein tyrosine kinases (JAK)/signal transducer and activator of the transcription (STAT) activation. The identification of noncanonical JAK/STAT-independent signaling pathways downstream of IL-24 relies on the interaction of IL-24 with protein kinase R in the cytosol, respiratory chain proteins in the inner mitochondrial membrane, and chaperones such as Sigma 1 Receptor in the endoplasmic reticulum. Numerous studies have shown that enhancing or inhibiting the expression of Interleukin 24 has a therapeutic effect in animal models and clinical trials in different pathologies. Successful drug targeting will require a deeper understanding of the downstream signaling pathways. In this review, we discuss the signaling pathway triggered by IL-24.