Viruses constitute a significant group of pathogens that have caused numerous fatalities and substantial economic losses in recent years, particularly with the emergence of coronaviruses. While the impact of SARS-CoV-2 appears to be diminishing in daily life, only a limited number of drugs have received approval or emergency use authorization for its treatment. Given the high mutation rate of viral genomes, host-directed agents (HDAs) have emerged as a preferred choice due to their broad applicability and lasting effectiveness. In contrast to direct-acting antivirals (DAAs), HDAs offer several advantages, including broad-spectrum antiviral activities, potential efficacy against future emerging viruses, and a lower likelihood of inducing drug resistance. In our review article, we have synthesized known host-directed antiviral targets that span diverse cellular pathways and mechanisms, shedding light on the intricate interplay between host cells and viruses. Additionally, we have provided a brief overview of the development of HDAs based on these targets. We aim for this comprehensive analysis to offer valuable perspectives and insights that can guide future antiviral research and drug development efforts.

Human respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and young children, as well as an important cause of respiratory tract infections in immunocompromised patients and the elderly, which poses a significant economic and social burden worldwide. In recent years, substantial progress has been made in understanding the structure and function of RSV proteins and the interactions between RSV with host factors which is helpful to the discovery of new therapeutic targets and the development of novel interventions. Although two vaccines and two monoclonal antibodies for RSV prevention have been approved, the antiviral treatment remains an unmet clinical need. In this review, we summarize the structure, protein functional properties, and pathological mechanisms of RSV and the current status of RSV drug development. In addition, remaining challenges and innovative ideas for RSV prevention and treatment have also been highlighted.

As the most abundant and essential structural protein in the human body, collagen is ubiquitously present in the interstitium of nearly all solid organs, playing a crucial role in maintaining the structural integrity and functional stability of human tissues and organs. Disorders associated with collagen structure and metabolisms impose a significant burden on society and healthcare systems. Post-translational modifications (PTMs) are essential steps in collagen metabolism, and recent studies have indicated that aberrant regulation of PTMs plays a pivotal role in the pathogenesis and progress of collagen-related disorders, including liver, kidney, heart, lung, and skin fibrosis, as well as keloid. This review provides a comprehensive summary of the regulatory mechanisms of both traditional and novel PTMs in collagen metabolism and collagen-related diseases. Furthermore, we summarize the drugs that modulate PTMs and their effects, with the aim of elucidating the pathophysiology of collagen-related diseases and provide new insights for their diagnosis, prevention, and treatment.

Adjuvants as essential ingredients amplify the magnitude and durability of immune responses in various vaccine strategies. Polysaccharides with potent immunoenhancing effects are widely applied as promising vaccine adjuvants, however, they have rarely been licensed for use in human vaccines due to the limitation of their efficacy and safety. Moreover, nanoparticles not only act as antigen drug delivery vectors but also possess intrinsic adjuvant functions, revealing the dual effects of nanoparticles in augmenting antigen-specific immune responses. Intriguingly, nanoparticle forms can enhance the immunostimulatory potency of polysaccharide adjuvants, since polysaccharide nanoparticles exert more excellent adjuvant effects than polysaccharides in initiating humoral, cellular and mucosal immune responses. Emerging evidence has also suggested that multiple immune-related signaling pathways including cGAS–STING, NLRP3, TLRs, cell death or metabolism signaling probably participate in the immunomodulation of polysaccharide nanoparticles, but systemic investigations into the adjuvant mechanism are still inadequate. This review aims to give an updated summary and discussion on the adjuvant function and mechanism of polysaccharide nanoparticles for understanding their superior adjuvant property and effectively utilizing them as potent immune adjuvants in vaccine development.

As the intricate interplay between microbiota and the host garners increasing research attention, a significant parallel surge has emerged in the investigation of intestinal bacterial extracellular vesicles (BEVs). Most intestinal bacteria secrete BEVs, which harbor specific cargo molecules and exhibit diverse functions, encompassing interactions among bacteria themselves and between bacteria and the host. These interactions can either bolster host health or contribute to various pathologies. By integrating the characteristics of BEVs, we summarized the current research landscape, delving into the intricate interplay between BEVs and different diseases. Furthermore, we offer a succinct overview of the challenges faced in BEVs-based research, encompassing separation, detection, engineering for drug purposes, clinical diagnostics, safety, and future study. In essence, these summaries may serve as invaluable guides for BEVs as communication tools between the gut microbiome and host, ultimately propelling the discovery of novel studies and drug discovery.

Tumor metastasis is the leading cause of high mortality in most cancers, and numerous studies have demonstrated that the malignant crosstalk of multiple components in the tumor microenvironment (TME) together promotes tumor metastasis. Cancer-associated fibroblasts (CAFs) are the major stromal cells and crosstalk centers in the TME of various kinds of tumors, such as breast cancer, pancreatic cancer, and prostate cancer. Recently, the CAF-induced pro-tumor metastatic TME has gained wide attention, being considered as one of the effective targets for tumor therapy. With in-depth research, CAFs have been found to promote tumor metastasis through multiple mechanisms, such as inducing epithelial–mesenchymal transition in tumor cells, remodeling the extracellular matrix, protecting circulating tumor cells, and facilitating the formation of a pre-metastatic niche. To enhance the anti-tumor metastasis effect, therapeutic strategies designed by combining nano-drug delivery systems with CAF modulation are undoubtedly a desirable choice, as evidenced by the research over the past decades. Herein, we introduce the physiological properties of CAFs, detail the possible mechanisms whereby CAFs promote tumor metastasis, categorize CAFs-based nano-drug delivery strategies according to their anti-metastasis functions and discuss the current challenges, possible solutions, as well as the future directions in order to provide a theoretical basis and reference for the utilization of CAFs-based nano-drug delivery strategies to promote tumor metastasis therapy.

Cancer immunotherapy has emerged as a promising strategy. However, low response rates and immune-related side effects have plagued immunotherapy. Metallic nanoparticles, utilizing metals as their framework, are gaining prominence in cancer immunotherapy. Metal ions have shown the ability to modulate immune status by activating the cGAS–STING pathway and inducing immunogenic cell death (ICD), thereby enabling multidimensional activation of immunotherapy. Metallic nanoparticles offer significant advantages in cancer immunotherapy, leading to their increasing use in enhancing therapeutic outcomes. In view of the ever-increasing research on metallic nanoparticles, this review presents the construction, characterization, and enhanced cancer immunotherapeutic effects of different types of metal nanosystems from the perspective of the immunoregulatory mechanisms of metal ions. We delve into the current limitations and future directions of metallic nanoparticles in this rapidly evolving field. To the best of our knowledge, this review offers the most up-to-date and systematic analysis of metallic nanoparticles in immunotherapeutic applications. It is anticipated that this review of metallic nanoparticles will inspire a more refined and intelligent design of metallic nanoparticles for future research, paving the way for advancing their clinical applications.

Fifty whitespotted bamboo sharks (Chiloscyllium playgiosum) of both sexes were used to establish a large capacity variable domain of the new antigen receptor (VNAR) library with a total capacity of over 10⁹ colony-forming units (CFU). It was applied to screen VNARs against human serum albumin (HSA) and human transcription factor EB (TFEB), respectively. Meanwhile, VNAR libraries specific to HSA and TFEB with capacities above 10⁸ CFU were obtained following conventional immunization. These two approaches were systematically studied in terms of VNAR yield and composition. By comparing the VNAR sequences obtained from naïve and antigen-immunized libraries, we found that the complementary-determining region 3 (CDR3) of the former differs in composition from that of the latter. It shares a higher degree of homology with the naïve library. Meanwhile, the binding efficiency assessed by ELISA is also different between the naïve and antigen-immunized libraries. The binding of VNARs from the TFEB-immunized library appeared to surpass that observed with the naïve libraries, whereas the performance of VNARs from the HSA-immunized library indicated that both the immunized and naïve libraries for HSA had positive binding responses in polyclonal and monoclonal ELISA. The results are useful to develop novel diagnostic and therapeutic products based on shark VNARs.

The Janus kinase/signal transducers and activators of transcription (JAK–STAT) control natural killer (NK) cells development and cytotoxic functions, however, whether long non-coding RNAs (lncRNAs) are involved in this pathway remains unknown. We found that miR155HG was elevated in activated NK cells and promoted their proliferation and effector functions in both NK92 and induced-pluripotent stem cells (iPSCs)-derived NK (iPSC-NK) cells, without reliance on its derived miR-155 and micropeptide P155. Mechanistically, miR155HG bound to miR-6756 and relieved its repression of JAK3 expression, thereby promoting the JAK–STAT pathway and enhancing NK cell proliferation and function. Further investigations disclosed that upon cytokine stimulation, STAT3 directly interacts with miR155HG promoter and induces miR155HG transcription. Collectively, we identify a miR155HG-mediated positive feedback loop of the JAK–STAT signaling. Our study will also provide a power target regarding miR155HG for improving NK cell generation and effector function in the field of NK cell adoptive transfer therapy against cancer, especially iPSC-derived NK cells.

Colorectal cancer (CRC) poses a severe global health challenge with high incidence and mortality rates. USP37 has been identified as the bona fide deubiquitinase of SND1, playing a critical role in stabilizing SND1, thereby augmenting its oncogenic potential. The interaction between USP37 and SND1 was confirmed through extensive proteomics, ubiquitinomics, and interactomics, underscoring their synergistic effects on CRC proliferation and metastasis. Additionally, CDK1 has emerged as a pivotal regulator of USP37, phosphorylating it at threonine 631 rather than serine 628, enhancing its deubiquitinase activity, and consequently stabilizing SND1 to drive CRC malignancy further. Histological analyses of human CRC samples linked the upregulation of CDK1 and USP37 with increased SND1 levels and poor patient prognosis. High-throughput virtual screening and subsequent experimental validation identified Dacarbazine as a pharmacological inhibitor of USP37, and its inhibition disrupted SND1 stability, hindering CRC cell proliferation and metastasis. This study reveals a novel and promising molecular mechanism driving CRC progression through the CDK1–USP37–SND1 axis, highlighting the clinical importance of targeting this pathway to improve patient outcomes.

G protein-coupled receptor kinase 2 (GRK2) participates in the phosphorylation and desensitization of G protein-coupled receptor (GPCR), impacting various biological processes such as inflammation and cell proliferation. Dysregulated expression and activity of GRK2 have been reported in multiple cells in rheumatoid arthritis (RA). However, whether and how GRK2 regulates synovial hyperplasia and fibroblast-like synoviocytes (FLSs) proliferation is poorly understood. In this study, we investigated the regulation of GRK2 and its biological function in RA. We found that GRK2 transmembrane activity was increased in FLSs of RA patients and collagen-induced arthritis (CIA) rats. Additionally, we noted a positive correlation between high GRK2 expression on the cell membrane and serological markers associated with RA and CIA. Immunoprecipitation–mass spectrometry and pull-down analyses revealed tumor necrosis factor receptor-associated factor 2 (TRAF2) as a novel substrate of GRK2. Furthermore, surface plasmon resonance (SPR) and molecular docking assays determined that the C-terminus of GRK2 binds to the C-terminus of TRAF2 at the Gln340 residue. GRK2 knockdown and the GRK2 inhibitor CP-25 attenuated synovial hyperplasia and FLS proliferation in CIA both in vitro and in vivo by decreasing GRK2 membrane expression and activity. Mechanistically, increased GRK2 transmembrane activity contributed to the recruitment of TRAF2 on the cell membrane, promoting GRK2–TRAF2 interactions that facilitate the recruitment of the E3 ubiquitin ligase TRIM47 to TRAF2. This enhanced TRAF2 Lys63 polyubiquitylation and induced nuclear factor (NF)-κB activation, leading to synovial hyperplasia and abnormal proliferation of FLSs. Our study provides a mechanistic and preclinical rationale for further evaluation of GRK2 as a therapeutic target for RA.

Obesity is a significant risk factor for cancer and is associated with breast cancer metastasis. Nevertheless, the mechanism by which alterations in systemic metabolism affect tumor microenvironment (TME) and consequently influence tumor metastasis remains inadequately understood. Herein, we found that perturbations in circulating metabolites induced by obesity promote metastasis-like phenotypes in breast cancer. Oleoylcarnitine (OLCarn) concentrations were elevated in the serum of obese mice and humans. Administration of exogenous OLCarn induces metastasis-like characteristics in breast cancer cells. Mechanistically, OLCarn directly interacts with the Arg176 site of adenylate cyclase 10 (ADCY10), leading to the activation of ADCY10 and enhancement of cAMP production. Mutations at Arg176 prevent OLCarn from binding to ADCY10, disrupting the ADCY10-mediated activation of cyclic adenosine monophosphate (cAMP) signaling pathway. This activation promotes transcription factor 4 (TCF4)-dependent kinesin family member C1 (KIFC1) transcription, thereby driving breast cancer metastasis. Conversely, the neutralization of both ADCY10 and KIFC1 through knockdown or pharmacological inhibition abrogates the oncogenic effects mediated by OLCarn. Hence, obesity-induced systemic environmental changes lead to the aberrant accumulation of OLCarn within the TME, making it a potential therapeutic target and biomarker for breast cancer.

Most cancers are currently incurable, partly due to abnormal post-translational modifications (PTMs). In this study, we initially used multiple myeloma (MM) as a working model and found that SUMOylation activating enzyme subunit 1 (SAE1) promotes the malignancy of MM. Through proteome microarray analysis, SAE1 was identified as a potential target for bioactive colcemid or its derivative colchicine. Elevated levels of SAE1 were associated with poor clinical survival and increased MM proliferation in vitro and in vivo. Additionally, SAE1 directly SUMOylated and upregulated the total protein expression of p27, leading to LLPS-mediated nuclear export of p27. Our study also demonstrated the involvement of SAE1 in other types of cancer cells, and provided the first monomer crystal structure of SAE1 and its key binding model with colchicine. Colchicine also showed promising results in the Patient-Derived Tumor Xenograft (PDX) model. Furthermore, a controlled clinical trial with 56 MM patients demonstrated the clinical efficacy of colchicine. Our findings reveal a novel mechanism by which tumor cells evade p27-induced cellular growth arrest through p27 SUMOylation-mediated nuclear export. SAE1 may serve as a promising therapeutic target, and colchicine may be a potential treatment option for multiple types of cancer in clinical settings.

Glioma is difficult to treat due to the unique tumor microenvironment and blood–brain barrier. (13aS)-3-Hydroxyl-6,7-dimethoxyphenanthro[9,10-b] indolizidine (PF403), a phenanthroindolizidine alkaloid, has been identified as a promising therapeutic agent for the treatment of glioma. However, the anti-glioma mechanism of PF403 in vivo has not been conclusively verified and must be further elucidated. Hence, a strategy without chemical modification was applied to identify the target of PF403. In this study, we identified nicotinamide phosphoribosyl transferase (NAMPT) as the target of PF403 by using thermal proteome profiling (TPP). Moreover, microscale thermophoresis (MST), surface plasmon resonance (SPR), and isothermal titration calorimetry (ITC) experiments confirmed that NAMPT exhibits good affinity for PF403. Direct and indirect enzyme activity assays revealed that PF403 inhibited the catalytic activity of NAMPT, leading to a decrease in the concentration of nicotinamide adenine dinucleotide (NAD⁺) in U87 cells. X-ray diffraction and amino acid spot mutation experiments revealed that PF403 primarily relies on the formation of pi–pi interactions with residue Tyr188 to maintain binding with NAMPT (PDB code 8Y55). After NAMPT was knocked down with lentivirus, PF403 lost or partially lost its antitumor activity at the cellular and animal levels. These findings suggest that PF403 exerts antitumor activity by directly targeting NAMPT.

Although enteric glial cell (EGC) abnormal activation is reported to be involved in the pathogenesis of Parkinson's disease (PD), and inhibition of EGC gliosis alleviated gut and dopaminergic neuronal dysfunction was verified in our previous study, the potential role of gut microbiota on EGC function in PD still need to be addressed. In the present study, fecal microbiota transplantation revealed that EGC function was regulated by gut microbiota. By employing 16S rRNA and metabolomic analysis, we identified that 3-indolepropionic acid (IPA) was the most affected differential microbial metabolite that regulated EGC gliosis. The protective effects of IPA on PD were validated in rotenone-stimulated EGCs and rotenone (30 mg/kg i.g. for 4 weeks)-induced PD mice, as indicated by decreased inflammation, improved intestinal and brain barrier as well as dopaminergic neuronal function. Mechanistic study showed that IPA targeted pregnane X receptor (PXR) in EGCs, and inhibition of IL-13Rα1 involved cytokine–cytokine receptor interaction pathway, leading to inactivation of downstream JAK1–STAT6 pathway. Our data not only provided evidence that EGC gliosis was critical in spreading intestinal damage to brain, but also highlighted the potential role of microbial metabolite IPA in alleviating PD pathological damages through gut–brain axis.

Resistance to ferroptosis, a form of regulated cell death caused by disruptions in iron ion and intracellular redox homeostasis, is closely related to tumorigenesis and tumor drug resistance; therefore, targeting ferroptosis-related pathways has garnered attention as a potential antitumor therapeutic strategy. However, the molecular mechanisms underlying ferroptosis resistance in tumor cells remain unknown. Zinc-finger estrogen receptor interaction clone 6 (ZER6) consists of two isoforms with distinct N-termini, p52-ZER6 and p71-ZER6. ZER6 is upregulated in tumors and promotes tumorigenic potential; however, whether ZER6 is involved in tumor cell ferroptosis resistance remains unknown. Herein, we identified p52-ZER6 as a novel regulator of tumor cell ferroptosis resistance. p52-ZER6 promotes the transcriptional activity of DAZAP1, an RNA-binding protein. DAZAP1, in turn, enhances the stability of SLC7A11 mRNA by binding to its 3′-UTR region, thereby increasing SLC7A11 expression and cellular glutathione levels. This subsequently reduces lipid peroxide accumulation and enhances tumor cell ferroptosis resistance, eventually promoting tumorigenic potential. These findings reveal a new function of p52-ZER6 in regulating SLC7A11 mRNA stability via DAZAP1, ultimately leading to ferroptosis resistance and tumorigenic potential. Additionally, we also suggest targeting p52-ZER6 as a potential strategy to promote the efficacy of ferroptosis-based antitumor therapies.

Taxifolin (TAX) is a natural compound known for its liver protection effect, but the mechanism remains unknown. Phosphorylated proteomics analyses discovered that the phosphorylation level of NDRG1 at T328 was a key event of TAX-improved liver fibrosis. We established models with NDRG1 knockout (KO) in vivo and in vitro, demonstrating that NDRG1 KO attenuated the development of hepatocyte injury, and combining NDRG1 KO and TAX administration did not result in a reduction in protection against liver injury. Cellular thermal shift assay and surface plasma resonance analysis showed that TAX directly binds to NDRG1 rather than its upstream kinase, subsequently demonstrating that TAX regulated phosphorylation of NDRG1 at T328 through binding to its C289 site. NDRG1 T328A (phosphorylated mutation) and T328E (mimic phosphorylation) in vivo and in vitro confirmed that pNDRG1_T328 exacerbates hepatocyte injury along with DNA damage, inflammatory response, and apoptosis, thereby contributing to hepatic stellate cells (HSCs) activation. In contrast, TAX can inhibit the above pathological abnormalities and block hepatocyte injury-triggered HSCs activation and fibrosis. Overall, TAX is a potent liver protection drug primarily targeting NDRG1 and inhibiting pNDRG1_T328 in hepatocytes.

Hepatic ischemia-reperfusion injury (HIRI) has been considered as an inevitable process of liver transplantation. Hepatocyte ferroptosis is a key factor in HIRI development, yet precise mechanism and potential therapies are still unclear. Here, we demonstrated a strong correlation between hepatocyte ferroptosis and the downregulation of poly(rC)-binding protein (PCBP2), which compromised the stability of antiporter system Xc^– (consisted of SL3A2/SLC7A11). Besides, inhibiting PCBP2 contributed to facilitating cofactor p300 to enhance the transcriptional activity of HIF1α, leading to the expression and secretion of HMGB1. Then, released HMGB1 from ferroptotic hepatocytes worsened M1 macrophage recruitment and immune response during HIRI. Additionally, acteoside (ACT) was shown to assist PCBP2 in stabilizing the mRNA stability of Slc3a2 and Slc7a11, as well as enhance the binding affinity of PCBP2–system Xc^–. Beyond that, ACT also supported PCBP2 to limit HMGB1-induced M1 macrophage recruitment through imposing restrictions on p300 and HIF1α. Furthermore, specific knockdown of PCBP2 in hepatocytes directly interposed the therapeutic efficacy of ACT on HIRI mice. In conclusion, ACT alleviated hepatocyte ferroptosis and HIRI via promoting PCBP2 to maintain the stability of system Xc^– and limit HIF1α/p300–HMGB1 signaling. These findings highlight the therapeutic benefits of ACT in treating HIRI and offer insights into innovative therapeutic strategies.

The elevated polyamines, amine-rich molecules with diverse functions in pathophysiology processes, are implicated in contributing to tumorigenesis and progression. Whether and how they affect the efficacy of chemotherapy is incompletely understood. Our screening assays reveal that the supplement with a low dose of spermidine (Spd), one of the polyamines, enhances ferroptosis in prostate cancer cells as evidenced by increased lipid peroxidation and intracellular Fe²⁺ levels in vitro. Combination treatment with Spd and a low dose of ferroptosis inducer erastin synergistically augments anti-tumor efficacy with undetectable toxicity in mice. Analysis of RNA-seq data indicates that heme oxygenase 1 (HMOX1), an enzyme that catalyzes the cleavage of heme to release Fe²⁺, is significantly upregulated in response to Spd and erastin cotreatment. Spd mediated the hypusine modification of the eukaryotic initiation factor 5A (EIF5A) promotes the translation of the nuclear factor erythroid 2-related factor 2 (NRF2), subsequently leading to elevation of HMOX1. Moreover, Spd and erastin significantly inhibit proteasome activity which results in a decrease in proteasomal degradation of NRF2, although many proteasome-related genes are induced either by Spd or Spd plus erastin. Thus, in addition to its pro-oncogenic activity, the supplement of Spd improves antitumor activity in combination with ferroptosis inducers and offers an optional approach to cancer treatment.

During liver injury, intrahepatic macrophage compartment is augmented by circulating monocytes that infiltrate the liver driven by C–C motif chemokine ligand/C–C motif chemokine receptor (CCL/CCR) axis including CCL1‒CCR8 axis, thereby contributing to liver inflammation. Numerous small molecular receptor antagonists, including R243, have been developed for targeting CCR8; however, these agents face challenges in clinical translation, potentially attributed to their poor pharmacokinetic profiles, lack of target specificity, and potential adverse effects. In this study, we designed four CCR8 antagonizing peptides (AP8i-AP8iv) and performed molecular characterization in silico and therapeutic investigation in vitro and in vivo. Based on in silico docking, molecular dynamic simulation using homology build model and in-vitro (competitive) binding studies, AP8ii (YEWRFYHG) evidenced highly favorable and selective interactions at the CCR8-active site. AP8ii inhibited CCL1-driven chemotaxis and LPS/IFNγ-induced pro-inflammatory activation of monocytes-macrophages in vitro. In a CCl₄-induced acute liver injury mouse model, AP8ii treatment decreased intrahepatic infiltration of circulating monocytes. Moreover, AP8ii reduced liver inflammation, as indicated by decreased F4/80, IL6 and iNOS expression, diminished ALT levels, and attenuated fibrosis, as indicated by reduced collagen-I expression. In conclusion, we report a novel CCR8-antagonizing peptide that inhibited CCL1-driven intrahepatic monocytes infiltration and differentiation into pro-inflammatory phenotype, consequently ameliorating liver inflammation and fibrogenesis in an acute liver injury mouse model.

Alzheimer's disease (AD) is a common neurodegenerative disorder among the elderly, and BuChE has emerged as a potential therapeutic target. In this study, we reported the development of compound 8e, a selective reversible BuChE inhibitor (eqBuChE IC₅₀ = 0.049 μmol/L, huBuChE IC₅₀ = 0.066 μmol/L), identified through extensive virtual screening and lead optimization. Compound 8e demonstrated favorable blood–brain barrier permeability, good drug-likeness property and pronounced neuroprotective efficacy. Additionally, 8e exhibited significant therapeutic effects in zebrafish AD models and scopolamine-induced cognitive impairments in mice. Further, 8e significantly improved cognitive function in APP/PS1 transgenic mice. Proteomics analysis demonstrated that 8e markedly elevated the expression levels of very low-density lipoprotein receptor (VLDLR), offering valuable insights into its potential modulation of the Reelin-mediated signaling pathway. Thus, compound 8e emerges as a novel and potent BuChE inhibitor for the treatment of AD, with significant implications for further exploration into its mechanisms of action and therapeutic applications.

Membrane protein degradation is a cutting-edge field in targeted protein degradation (TPD). Herein, we developed glypican-3 (GPC3)-mediated lysosome-targeting chimeras (GLTACs) as a novel strategy for the targeted degradation of tumor-specific membrane proteins. GLTACs utilize tumor-specific expression and endocytosis properties of GPC3 to degrade membrane proteins. By conjugating a GPC3-targeting peptide with the ligand of protein of interest (POI), GLTACs induce the formation of a ternary complex that is internalized into lysosomes, leading to the degradation of the POI. The effectiveness and specificity of GLTACs were validated by designing PD-L1, c-Met, and FGFR1 degraders. In particular, GLTAC WP0 potently degraded PD-L1 and induced T-cell-mediated tumor killing against HepG2 cells, highlighting the potential therapeutic applications. The development of GLTAC technology expands the scope of TPD strategies and opens new avenues for discovering novel therapeutic modalities against challenging protein targets.

Interfering hepatitis B virus (HBV) capsid assembly holds promise as a therapeutic approach for chronic hepatitis B (CHB). Novel anti-HBV agents are urgently needed to overcome drug resistance challenges, with targeted protein degradation (TPD) emerging as a hopeful strategy. Herein, we report the first degradation of HBV core protein (HBC), a multifunctional structural protein, using small-molecule degraders developed by hydrophobic tagging (HyT) technology. Structure–activity relationship (SAR) analysis identified compound HyT-S7, featuring an adamantyl group, exhibiting potent inhibitory activity (EC₅₀ = 0.46 μmol/L, HepAD38 cells) and degradation ability (DC₅₀ = 3.02 ± 0.54 μmol/L) in a dose- and time-dependent manner. Mechanistic studies demonstrated that the autophagy–lysosome pathway was a potential driver of HyT-S7-induced HBC degradation. Remarkably, HyT-S7 effectively degraded 11 drug-resistant mutants, including highly resistant strains P25G and T33N, to Phase III drug GLS4. Furthermore, cellular thermal shift assay, surface plasmon resonance assay, and molecular dynamics simulations revealed the precise mode of HyT-S7 binding to HBC with the adamantyl group potentially mimicking protein misfolding to facilitate HBC degradation. This first proof-of-concept study highlights the potential of HyT-mediated TPD in HBC as a promising avenue for discovering novel HBV and other antiviral agents with favorable drug resistance profiles.

Due to the difficulty of overcoming the abnormal epidermal barriers and addressing S. aureus infections without disrupting indigenous skin microbiota, effective treatment of bacterial infection atopic dermatitis (AD) remains a significant clinical challenge. Skin microbiota-derived extracellular vesicles (EVs) shows protentional for skin disease treatment, but the lack of antimicrobial activity and limited skin penetration hamper their application in bacterial infection AD treatment. Here, we developed novel nanoantibiotics by loading Lev into S. epidermidis-derived EVs (Lev@SE-EVs), with supreme antimicrobial activity, regulating epidermal immune responses and enhanced epidermal barrier functionality. The nanoantibiotics were further integrated into hyaluronic acid-based microneedle (MN) for efficient transdermal delivery of therapeutic agents and effectively treating bacterial infection in AD. Upon insertion into the skin, the rapidly released Lev@SE-EVs from MN are uptake by S. aureus in a selective manner, fibroblasts, and surrounding immune cells to exert therapeutic effects in the infected dermal layer, resulting in mitigated skin inflammation, reduced S. aureus burden and increased dermis repair. Notably, Lev@SE-EVs induce IL-17A⁺ CD8⁺ T-cell accumulation in the skin in an unrelated inflammation manner, which may represent heterologous protection. This EVs-integrated MN assisted Lev@SE-EVs to alleviate skin inflammation, repair skin, and provide an effective and safe therapeutic approach for bacterial infection AD treatment.

Probiotics are natural systems bridging synthetic biology, physical biotechnology, and immunology, initiating innate and adaptive anti-tumor immune activity. We previously constructed an all-in-one engineered food-grade probiotic Lactococcus lactis (FOLactis) which could boost the crosstalk among different immune cells such as dendritic cells (DCs), natural killer cells, and T cells. Herein, considering the limited clinical efficacy of naked personalized neoantigen peptide vaccines, we decorate FOLactis with tumor antigens by employing a Plug-and-Display system comprising membrane-inserted peptides. Intranodal injection of FOLactis coated with neoantigen peptides (Ag-FOLactis) induces robust DCs presentation and neoantigen-specific cellular immunity. Notably, Ag-FOLactis not only triggers a 45-fold rise in the quantity of locally reactive neoantigen-specific T cells but also induces epitope spreading in both subcutaneous and metastatic tumor-bearing models, leading to potent inhibition of tumor growth. These findings imply that Ag-FOLactis represents a powerful platform to rapidly and easily display antigens, facilitating the development of a bio-activated platform for personalized therapy.

Among tumor microenvironment (TME), the entire metabolic characteristics of tumor-resident cells are reprogrammed to benefit the expansion of tumor cells, which count on glutamine in large part to fuel the tricarboxylic acid cycle for energy generation and anabolic metabolism support. Endothelial cells that are abducted by tumor cells to form a pathological tumor vascular network for constructing the hypoxic immunosuppressive TME, also rely on glutaminolysis as the “engine” of angiogenesis. Additionally, the glutamine metabolic preference benefits the polarization of TAMs towards pro-tumoral M2 phenotype as well. Herein, we developed a type of siRNA micelleplexes (MH@siGLS1) to reverse immunosuppressive TME by targeting glutaminolysis within tumor-resident cells for tumor vasculature normalization- and TAMs repolarization-enhanced photo-immunotherapy. Tumor cell starvation and antioxidant system destruction achieved by MH@siGLS1-mediated glutaminolysis inhibition could promote photodynamic therapy efficacy, which was available to trigger immunogenic cell death for adaptive antitumor immune responses. Meanwhile, glutaminolysis inhibition of tumor endothelial cells and TAMs could realize tumor vascular normalization and TAMs repolarization for antitumor immunity amplification. This study provides a unique perspective on cancer treatments by focusing on the interrelations of metabolic characteristics and the biofunctions of various cell types within TME.

Dendrobium moniliforme (D. moniliforme) is a traditional medicinal herb widely cultivated in Asia. Flavonoids, one of the largest groups of secondary metabolites in plants, are significant medicinal components in Dendrobium species. Several subgroups of R2R3-MYB proteins have been validated to directly regulate flavonoid biosynthesis. Using PacBio sequencing technology, we assembled a high-quality chromosome-level D. moniliforme genome with a total length of 1.20 Gb and a contig N50 of 3.97 Mb. The BUSCO assessment of genome annotation was 91.4%. By integrating the genome and transcriptome, we identified biosynthesis pathway enzyme genes related to flavonoids, polysaccharides, carotenoids, and alkaloids. A total of 90 R2R3-MYBs were identified in D. moniliforme and classified into 21 subgroups. Studies on the functions of R2R3-MYB transcription factors revealed that R2R3-MYB in SG6 can up-regulate flavonoid biosynthesis. Various validation experiments, including subcellular localization, transient overexpression, UPLC–MS/MS, HPLC, yeast one-hybrid, and dual-luciferase assays, demonstrated that DMYB69 directly up-regulates the expression of enzyme genes involved in flavonoid biosynthesis, increasing the content of flavonoids such as anthocyanin, flavone, and flavonol. Additionally, DMYB44 was shown to directly up-regulate the expression of carotenoid biosynthesis enzyme genes, thereby increasing carotenoid content. This study provides an essential genome resource and theoretical basis for molecular breeding research in D. moniliforme.