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1.
J Transl Med ; 22(1): 840, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39267037

ABSTRACT

BACKGROUND: The tumor microenvironment (TME) exerts profound effects on tumor progression and therapeutic efficacy. In hepatocellular carcinoma (HCC), the TME is enriched with cancer-associated fibroblasts (CAFs), which secrete a plethora of cytokines, chemokines, and growth factors that facilitate tumor cell proliferation and invasion. However, the intricate architecture of the TME in HCC, as well as the mechanisms driving interactions between tumor cells and CAFs, remains largely enigmatic. METHODS: We analyzed 10 spatial transcriptomics and 12 single-cell transcriptomics samples sourced from public databases, complemented by 20 tumor tissue samples from liver cancer patients obtained in a clinical setting. RESULTS: Our findings reveal that tumor cells exhibiting high levels of SPP1 are preferentially localized adjacent to hepatic stellate cells (HSCs). The SPP1 secreted by these tumor cells interacts with the CD44 receptor on HSCs, thereby activating the PI3K/AKT signaling pathway, which promotes the differentiation of HSCs into CAFs. Notably, blockade of the CD44 receptor effectively abrogates this interaction. Furthermore, in vivo studies demonstrate that silencing SPP1 expression in tumor cells significantly impairs HSC differentiation into CAFs, leading to a reduction in tumor volume and collagen deposition within the tumor stroma. CONCLUSIONS: This study delineates the SPP1-CD44 signaling axis as a pivotal mechanism underpinning the interaction between tumor cells and CAFs. Targeting this pathway holds potential to mitigate liver fibrosis and offers novel therapeutic perspectives for liver cancer management.


Subject(s)
Carcinoma, Hepatocellular , Chemotaxis , Hepatic Stellate Cells , Liver Neoplasms , Transcriptome , Tumor Microenvironment , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Humans , Transcriptome/genetics , Hepatic Stellate Cells/metabolism , Hepatic Stellate Cells/pathology , Animals , Chemotaxis/genetics , Fibroblasts/metabolism , Fibroblasts/pathology , Cell Line, Tumor , Signal Transduction , Hyaluronan Receptors/metabolism , Cancer-Associated Fibroblasts/metabolism , Cancer-Associated Fibroblasts/pathology , Cell Differentiation , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Gene Expression Regulation, Neoplastic
2.
Ren Fail ; 46(2): 2365979, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39108141

ABSTRACT

BACKGROUND: To explore the risk factors of proteinuria in Omicron variant patients and to construct and verify the risk predictive model. METHODS: 1091 Omicron patients who were hospitalized from August 2022 to November 2022 at Tianjin First Central Hospital were defined as the derivation cohort. 306 Omicron patients who were hospitalized from January 2022 to March 2022 at the same hospital were defined as the validation cohort. The risk factors of proteinuria in derivation cohort were screened by univariate and multivariate logistic regression analysis, and proteinuria predicting scoring system was constructed and the receiver operating characteristic(ROC)curve was drawn to test the prediction ability. The proteinuria risk model was externally validated in validation cohort. RESULTS: 7 factors including comorbidities, blood urea nitrogen (BUN), serum sodium (Na), uric acid (UA), C reactive protein (CRP) and vaccine dosages were included to construct a risk predictive model. The score ranged from -5 to 16. The area under the ROC curve(AUC) of the model was 0.8326(95% CI 0.7816 to 0.8835, p < 0.0001). Similarly to that observed in derivation cohort, the AUC is 0.833(95% CI 0.7808 to 0.9002, p < 0.0001), which verified good prediction ability and diagnostic accuracy in validation cohort. CONCLUSIONS: The risk model of proteinuria after Omicron infection had better assessing efficiency which could provide reference for clinical prediction of the risk of proteinuria in Omicron patients.


Subject(s)
COVID-19 , Proteinuria , SARS-CoV-2 , Humans , COVID-19/complications , Female , Male , Middle Aged , Retrospective Studies , Risk Factors , ROC Curve , Aged , Risk Assessment , Adult , China/epidemiology
3.
Int Immunopharmacol ; 141: 112955, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39163685

ABSTRACT

OBJECTIVES: Previous studies elucidated that capecitabine (CAP) works as an anti-tumor agent with putative immunosuppressive effects. However, the intricate mechanisms underpinning these effects remain to be elucidated. In this study, we aimed to unravel the molecular pathways by which CAP exerts its immunosuppressive effects to reduce allograft rejection. METHODS: Hearts were transplanted from male BALB/c donors to male C57BL/6 recipients and treated with CAP for seven days. The rejection of these heart transplants was assessed using a range of techniques, including H&E staining, immunohistochemistry, RNA sequencing, LS-MS/MS, and flow cytometry. In vitro, naïve CD4+ T cells were isolated and cultured under Th1 condition medium with varying treatments, flow cytometry, LS-MS/MS were employed to delineate the role of thymidine synthase (TYMS) during Th1 differentiation. RESULTS: CAP treatment significantly mitigated acute allograft rejection and enhanced graft survival by reducing graft damage, T cell infiltration, and levels of circulating pro-inflammatory cytokines. Additionally, it curtailed CD4+ T cell proliferation and the presence of Th1 cells in the spleen. RNA-seq showed that TYMS, the target of CAP, was robustly increased post-transplantation in splenocytes. In vitro, TYMS and its metabolic product dTMP were differentially expressed in Th0 and Th1, and were required after activation of CD4+ T cell and Th1 differentiation. TYMS-specific inhibitor, raltitrexed, and the metabolite of capecitabine, 5-fluorouracil, could inhibit the proliferation and differentiation of Th1. Finally, the combined use of CAP and the commonly used immunosuppressant rapamycin can induce long-term survival of allograft. CONCLUSION: CAP undergoes metabolism conversion to interfere pyrimidine metabolism, which targets TYMS-mediated differentiation of Th1, thereby playing a significant role in mitigating acute cardiac allograft rejection in murine models.


Subject(s)
Capecitabine , Cell Differentiation , Graft Rejection , Heart Transplantation , Immunosuppressive Agents , Mice, Inbred BALB C , Mice, Inbred C57BL , Th1 Cells , Animals , Graft Rejection/prevention & control , Graft Rejection/immunology , Graft Rejection/drug therapy , Male , Th1 Cells/immunology , Th1 Cells/drug effects , Cell Differentiation/drug effects , Mice , Capecitabine/therapeutic use , Capecitabine/pharmacology , Immunosuppressive Agents/pharmacology , Immunosuppressive Agents/therapeutic use , Graft Survival/drug effects , Graft Survival/immunology , Cytokines/metabolism , Cells, Cultured
4.
Hepatol Int ; 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39003652

ABSTRACT

BACKGROUND: The specific CT-related skeletal muscle parameters predictive of postoperative survival in liver transplant (LT) patients with hepatocellular carcinoma (HCC) remain unclear. There is increasing evidence supporting the role of fatty acids and their lipid intermediates in regulating skeletal muscle mass and function, the relationship between lipoprotein subfractions and body composition remains unclear. METHODS: Adult patients with HCC who underwent LT between January 2015 and September 2022 were retrospectively analyzed. CT parameters, including skeletal muscle index (SMI), psoas muscle index (PMI), skeletal muscle density (SMD), visceral and subcutaneous adipose tissue (VAT and SAT), and the VAT/SAT ratio at the L3 level, and lipid profiles, were assessed prior to LT. RESULTS: Of the 284 LT patients with HCC, 224 underwent CT (L3 level) within 3 months of LT, and 82 (37%) were diagnosed with myosteatosis. Patients with myosteatosis exhibited significantly lower 1- and 3-year survival rates (p = 0.002, p = 0.01), a trend persisting even beyond the Milan criteria (p = 0.004, p = 0.04). After adjusting for covariates, SMD demonstrated a significant negative correlation with post-transplant survival (HR: 0.90, [95% Confidence Interval(CI): 0.83-0.98], C-statistic: 0.78, p = 0.009). Pearson's correlation analysis revealed a positive correlation between high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A1(ApoA1) levels and SMD. Multivariate stepwise regression analysis demonstrated that every 10 Hounsfield unit decrease in SMD was associated with a 0.16 mmol/L decrease in HDL-C and a 0.18 g/L decrease in ApoA1. CONCLUSION: Routine abdominal CT scans for assessing skeletal muscle density before LT were significantly associated with post-transplant mortality. Furthermore, abnormal HDL-C and ApoA1 levels before LT were associated with myosteatosis.

5.
Crit Rev Anal Chem ; : 1-16, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38889541

ABSTRACT

Rapid, low-cost and high-specific diagnosis based on nucleic acid detection is pivotal in both detecting and controlling various infectious diseases, effectively curbing their spread. Moreover, the analysis of circulating DNA in whole blood has emerged as a promising noninvasive strategy for cancer diagnosis and monitoring. Although traditional nucleic acid detection methods are reliable, their time-consuming and intricate processes restrict their application in rapid field assays. Consequently, an urgent emphasis on point-of-care testing (POCT) of nucleic acids has arisen. POCT enables timely and efficient detection of specific sequences, acting as a deterrent against infection sources and potential tumor threats. To address this imperative need, it is essential to consolidate key aspects and chart future directions in POCT biosensors development. This review aims to provide an exhaustive and meticulous analysis of recent advancements in POCT devices for nucleic acid diagnosis. It will comprehensively compare these devices across crucial dimensions, encompassing their integrated structures, the synthesized nanomaterials harnessed, and the sophisticated detection principles employed. By conducting a rigorous evaluation of the current research landscape, this review will not only spotlight achievements but also identify limitations, offering valuable insights into the future trajectory of nucleic acid POCT biosensors. Through this comprehensive analysis, the review aspires to serve as an indispensable guide for fostering the development of more potent biosensors, consequently fostering precise and efficient POCT applications for nucleic acids.

6.
Int Immunopharmacol ; 138: 112533, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38924868

ABSTRACT

BACKGROUND: Hepatic ischemia-reperfusion (IR) injury is a major complication of liver transplantation and gravely affects patient prognosis. Icaritin (ICT), the primary plasma metabolite of icariin (ICA), plays a critical role in anti-inflammatory and immunomodulatory processes. However, the role of ICT in hepatic IR injury remains largely undefined. In this study, we aimed to elucidate the role of ICT in hepatic IR injury. METHODS: We established hepatic IR injury models in animals, as well as an oxygen-glucose deprivation/reperfusion (OGD/R) cell model. Liver injury in vivo was assessed by measuring serum alanine aminotransferase (ALT) levels, necrotic areas by liver histology and local hepatic inflammatory responses. For in vitro analyses, we implemented flow-cytometric and western blot analyses, transmission electron microscopy, and an mRFP-GFP-LC3 adenovirus reporter assay to assess the effects of ICT on OGD/R injury in AML12 and THLE-2 cell lines. Signaling pathways were explored in vitro and in vivo to identify possible mechanisms underlying ICT action in hepatic IR injury. RESULTS: Compared to the mouse model group, ICT preconditioning considerably protected the liver against IR stress, and diminished the levels of necrosis/apoptosis and inflammation-related cytokines. In additional studies, ICT treatment dramatically boosted the expression ratios of p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR proteins in hepatic cells following OGD/R damage. We also applied LY294002 (a PI3K inhibitor) and RAPA (rapamycin, an mTOR inhibitor), which blocked the protective effects of ICT in hepatocytes subjected to OGD/R. CONCLUSION: This study indicates that ICT attenuates ischemia-reperfusion injury by exerting anti-inflammation, anti-oxidative stress, and anti-autophagy effects, as demonstrated in mouse livers. We thus posit that ICT could have therapeutic potential for the treatment of hepatic IR injury.


Subject(s)
Anti-Inflammatory Agents , Autophagy , Flavonoids , Liver , Mice, Inbred C57BL , Oxidative Stress , Reperfusion Injury , Animals , Reperfusion Injury/drug therapy , Reperfusion Injury/metabolism , Flavonoids/pharmacology , Flavonoids/therapeutic use , Liver/pathology , Liver/drug effects , Liver/metabolism , Oxidative Stress/drug effects , Male , Mice , Autophagy/drug effects , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Cell Line , Disease Models, Animal , Humans , TOR Serine-Threonine Kinases/metabolism , Signal Transduction/drug effects , Hepatocytes/drug effects , Hepatocytes/metabolism
7.
J Zhejiang Univ Sci B ; 25(6): 451-470, 2024 Jun 15.
Article in English, Chinese | MEDLINE | ID: mdl-38910492

ABSTRACT

Interferon regulatory factor 1 (IRF-1) is a member of the IRF family. It is the first transcription factor to be identified that could bind to the interferon-stimulated response element (ISRE) on the target gene and displays crucial roles in the interferon-induced signals and pathways. IRF-1, as an important medium, has all of the advantages of full cell cycle regulation, cell death signaling transduction, and reinforcing immune surveillance, which are well documented. Current studies indicate that IRF-1 is of vital importance to the occurrence and evolution of multifarious liver diseases, including but not limited to inhibiting the replication of the hepatitis virus (A/B/C/E), alleviating the progression of liver fibrosis, and aggravating hepatic ischemia-reperfusion injury (HIRI). The tumor suppression of IRF-1 is related to the clinical characteristics of liver cancer patients, which makes it a potential indicator for predicting the prognosis and recurrence of liver cancer; additionally, the latest studies have revealed other effects of IRF-1 such as protection against alcoholic/non-alcoholic fatty liver disease (AFLD/NAFLD), cholangiocarcinoma suppression, and uncommon traits in other liver diseases that had previously received little attention. Intriguingly, several compounds and drugs have featured a protective function in specific liver disease models in which there is significant involvement of the IRF-1 signal. In this paper, we hope to propose a prospective research basis upon which to help decipher translational medicine applications of IRF-1 in liver disease treatment.


Subject(s)
Interferon Regulatory Factor-1 , Liver Diseases , Liver Neoplasms , Interferon Regulatory Factor-1/metabolism , Interferon Regulatory Factor-1/genetics , Humans , Liver Diseases/metabolism , Animals , Liver Neoplasms/metabolism , Signal Transduction , Liver Cirrhosis/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Reperfusion Injury , Cholangiocarcinoma/metabolism
8.
Cell Stem Cell ; 31(6): 850-865.e10, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38697109

ABSTRACT

Human pluripotent stem cell-derived ß cells (hPSC-ß cells) show the potential to restore euglycemia. However, the immature functionality of hPSC-ß cells has limited their efficacy in application. Here, by deciphering the continuous maturation process of hPSC-ß cells post transplantation via single-cell RNA sequencing (scRNA-seq) and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq), we show that functional maturation of hPSC-ß cells is an orderly multistep process during which cells sequentially undergo metabolic adaption, removal of negative regulators of cell function, and establishment of a more specialized transcriptome and epigenome. Importantly, remodeling lipid metabolism, especially downregulating the metabolic activity of ceramides, the central hub of sphingolipid metabolism, is critical for ß cell maturation. Limiting intracellular accumulation of ceramides in hPSC-ß cells remarkably enhanced their function, as indicated by improvements in insulin processing and glucose-stimulated insulin secretion. In summary, our findings provide insights into the maturation of human pancreatic ß cells and highlight the importance of ceramide homeostasis in function acquisition.


Subject(s)
Cell Differentiation , Ceramides , Homeostasis , Insulin-Secreting Cells , Pluripotent Stem Cells , Humans , Ceramides/metabolism , Insulin-Secreting Cells/metabolism , Insulin-Secreting Cells/cytology , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Animals
9.
J Leukoc Biol ; 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38513294

ABSTRACT

Macropinocytosis is a large-scale endocytosis process that is primarily observed in phagocytes as part of their cellular function to ingest antigens. Once phagocytes encounter gram-negative bacteria, the receptor proteins identify lipopolysaccharides (LPSs), which trigger radical membrane ruffles that gradually change to cup-like structures. The open area of the cups closes to generate vesicles called macropinosomes. The target bacteria are isolated by the cups and engulfed by the cells as the cups close. In addition to its ingestion function, macropinocytosis also regulates the AKT pathway in macrophages. In the current study, we report that macropinocytic cups are critical for LPS-induced AKT phosphorylation (pAKT) and cytokine expression in macrophages. High-resolution scanning electron microscope (SEM) observations detailed the macropinocytic cup structures induced by LPS stimulation. Confocal microscopy revealed that AKT and the kinase molecule mTORC2 were localized in the cups. The biochemical analysis showed that macropinocytosis inhibition blocked LPS-induced pAKT. RNA-Seq, qPCR, and ELISA analyses revealed that the inhibition of macropinocytosis or the AKT pathway causes a decrease in the expression of pro-inflammatory cytokines IL-6 and IL-1α. Moreover, activation of the transcription factor NF-κB, which regulates the cytokine expression downstream of the AKT/IκB pathway, was hindered when macropinocytosis or AKT were inhibited. These results indicate that LPS-induced macropinocytic cups function as signal platforms for the AKT pathway to regulate the cytokine expression by modulating NF-κB activity in LPS-stimulated macrophages. Based on these findings, we propose that macropinocytosis may be a good therapeutic target for controlling cytokine expression.

10.
Transplantation ; 108(8): 1769-1775, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38419149

ABSTRACT

BACKGROUND: Optimizing the immunosuppressive regimen is essential to improve the long-term outcomes of pediatric liver transplant recipients. METHODS: We conducted a prospective, randomized, open-label study to compare the safety and efficacy of 2 treatment approaches during pediatric liver transplantation: tacrolimus monotherapy following basiliximab induction (the study group) and a dual regimen of tacrolimus plus steroids (the control group). A total of 150 patients were enrolled, with 75 patients allocated to each group. RESULTS: In both groups, recipients achieved graft and recipient overall survival rates exceeding 93%, with no statistically significant differences between them. However, the study group exhibited a significantly lower incidence of acute cellular rejection (ACR), delayed occurrence of ACR, and an improved ACR-free survival rate at 2 y compared with the control group. Notably, the study group also showed a significant reduction in the incidence of de novo donor-specific antibodies at 3-mo and 2-y posttransplant. Furthermore, 6 mo after the transplant, the study group demonstrated significant improvements in weight-for-age Z score and height-for-age Z score. No notable differences were observed in postoperative complications or the incidence of liver fibrosis between the 2 groups. CONCLUSIONS: Basiliximab induction combine with tacrolimus (TAC) monotherapy is a safe and effective immunosuppressive regimen to reduce the episodes of ACR without influencing the development of liver fibrosis and graft and recipient survival rate after pediatric liver transplantation.


Subject(s)
Basiliximab , Drug Therapy, Combination , Graft Rejection , Graft Survival , Immunosuppressive Agents , Liver Transplantation , Tacrolimus , Humans , Liver Transplantation/adverse effects , Liver Transplantation/mortality , Basiliximab/therapeutic use , Basiliximab/administration & dosage , Tacrolimus/administration & dosage , Tacrolimus/therapeutic use , Tacrolimus/adverse effects , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Male , Female , Graft Rejection/prevention & control , Graft Rejection/immunology , Child , Prospective Studies , Child, Preschool , Graft Survival/drug effects , Infant , Treatment Outcome , Time Factors , Adolescent , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/therapeutic use , Recombinant Fusion Proteins/adverse effects
12.
bioRxiv ; 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38260345

ABSTRACT

Circular dorsal ruffles (CDRs), large-scale rounded membrane ruffles, function as precursors of macropinocytosis. We recently reported that CDRs are exposed in the Hep3B hepatocellular carcinoma cell line, while not in other hepatocellular carcinoma cell lines, indicating that the CDRs in Hep3B are associated with malignant potential. In this study, we investigated the cellular function of CDRs in Hep3B cells by focusing on the molecular mechanisms of the GTPase-activating protein ARAP1. ARAP1 was localized to the CDRs, the sizes of which were reduced by deletion of this protein. High-resolution scanning electron micrographs revealed that CDRs comprise small vertical lamellipodia, the expression pattern of which was disrupted in ARAP1 KO cells. Extracellular solute uptake, rate of cell growth, and malignant potential were attenuated in the KO cells. ARAP1 is also localized in Hep3B cell mitochondria, although not in those of the Huh7 hepatocellular carcinoma cell line. On the basis of these findings, we propose that the aberrant expression of ARAP1 in Hep3B cells modulates CDRs, thereby resulting in an excess uptake of nutrients as an initial event in cancer development. SUMMARY STATEMENT: ARAP1 regulates circular dorsal ruffles (CDRs) in the Hep3B HCC cell line and deletion of this protein attenuates malignant potential, thereby indicating the involvement of CDRs in cancer development.

13.
Nature ; 625(7993): 148-156, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37993710

ABSTRACT

The continuing emergence of SARS-CoV-2 variants highlights the need to update COVID-19 vaccine compositions. However, immune imprinting induced by vaccination based on the ancestral (hereafter referred to as WT) strain would compromise the antibody response to Omicron-based boosters1-5. Vaccination strategies to counter immune imprinting are critically needed. Here we investigated the degree and dynamics of immune imprinting in mouse models and human cohorts, especially focusing on the role of repeated Omicron stimulation. In mice, the efficacy of single Omicron boosting is heavily limited when using variants that are antigenically distinct from WT-such as the XBB variant-and this concerning situation could be mitigated by a second Omicron booster. Similarly, in humans, repeated Omicron infections could alleviate WT vaccination-induced immune imprinting and generate broad neutralization responses in both plasma and nasal mucosa. Notably, deep mutational scanning-based epitope characterization of 781 receptor-binding domain (RBD)-targeting monoclonal antibodies isolated from repeated Omicron infection revealed that double Omicron exposure could induce a large proportion of matured Omicron-specific antibodies that have distinct RBD epitopes to WT-induced antibodies. Consequently, immune imprinting was largely mitigated, and the bias towards non-neutralizing epitopes observed in single Omicron exposures was restored. On the basis of the deep mutational scanning profiles, we identified evolution hotspots of XBB.1.5 RBD and demonstrated that these mutations could further boost the immune-evasion capability of XBB.1.5 while maintaining high ACE2-binding affinity. Our findings suggest that the WT component should be abandoned when updating COVID-19 vaccines, and individuals without prior Omicron exposure should receive two updated vaccine boosters.


Subject(s)
Antibodies, Viral , COVID-19 Vaccines , COVID-19 , Immunization, Secondary , Immunologic Memory , SARS-CoV-2 , Animals , Humans , Mice , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Epitopes, B-Lymphocyte/immunology , Immunologic Memory/immunology , SARS-CoV-2/classification , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Mutation
14.
PLoS Pathog ; 19(12): e1011868, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38117863

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) XBB lineages have achieved dominance worldwide and keep on evolving. Convergent evolution of XBB lineages on the receptor-binding domain (RBD) L455F and F456L is observed, resulting in variants with substantial growth advantages, such as EG.5, FL.1.5.1, XBB.1.5.70, and HK.3. Here, we show that neutralizing antibody (NAb) evasion drives the convergent evolution of F456L, while the epistatic shift caused by F456L enables the subsequent convergence of L455F through ACE2 binding enhancement and further immune evasion. L455F and F456L evade RBD-targeting Class 1 public NAbs, reducing the neutralization efficacy of XBB breakthrough infection (BTI) and reinfection convalescent plasma. Importantly, L455F single substitution significantly dampens receptor binding; however, the combination of L455F and F456L forms an adjacent residue flipping, which leads to enhanced NAbs resistance and ACE2 binding affinity. The perturbed receptor-binding mode leads to the exceptional ACE2 binding and NAb evasion, as revealed by structural analyses. Our results indicate the evolution flexibility contributed by epistasis cannot be underestimated, and the evolution potential of SARS-CoV-2 RBD remains high.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Humans , Angiotensin-Converting Enzyme 2/genetics , SARS-CoV-2/genetics , COVID-19/genetics , COVID-19 Serotherapy , Antibodies, Neutralizing
15.
Int Immunopharmacol ; 124(Pt A): 110809, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37690240

ABSTRACT

Hepatic ischemia reperfusion injury (IRI) is a risk factor for early graft nonfunction and graft rejection after liver transplantation (LT). The process of liver IRI involves inflammatory response, oxidative stress, apoptosis and other pathophysiological processes. So far, there is still a lack of effective drugs to ameliorate liver IRI. Trans-anethole (TA) is an aromatic compound. Many medications as well as natural foods contain TA. TA has multiple effects such as anti-inflammation, anti-oxidative stress and anti-apoptosis. However, the mechanism of TA pretreatment in liver IRI is unclear. The mice hepatic IRI model was constructed after gavage pretreatment with TA (10 mg/kg, 20 mg/kg, 40 mg/kg) for 7 consecutive days. Our study confirmed that TA pretreatment significantly improve liver function and reduce serum AST, ALT in hepatic IRI. HE staining showed that TA pretreatment alleviated liver injury. Meanwhile, TA (20 mg/kg) pretreatment attenuated hepatocyte apoptosis in hepatic IRI. In addition, TA (20 mg/kg) pretreatment reduced the inflammatory factors TNF-α, IL-6 and infiltration of CD11b positive cells in liver tissues during hepatic IRI in mice. TA pretreatment also alleviated oxidative stress in mice hepatic IRI. Our study further indicated that TA pretreatment attenuated mice hepatic IRI through inhibiting NLRP3 inflammasome activation via regulation of soluble epoxide hydrolase (sEH). This study provides a novel and effective potential drug with few side effects for easing liver IRI.

17.
Int Immunopharmacol ; 124(Pt A): 110810, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37625370

ABSTRACT

Liver transplantation is one of the most effective treatments for hepatocellular carcinoma (HCC). The balance between inhibiting immune rejection and preventing tumor recurrence after liver transplantation is the key to determining the long-term prognosis of patients with HCC after liver transplantation. In our previous study, we found that capecitabine (CAP), an effective drug for the treatment of HCC, could exert an immunosuppressive effect after liver transplantation by inducing T cell ferroptosis. Recent studies have shown that ferroptosis is highly associated with autophagy. In this study, we confirmed that the autophagy inducer rapamycin (RAPA) combined with metronomic capecitabine (mCAP) inhibits glutathione peroxidase 4 (GPX4) and promotes ferroptosis in CD4+ T cells to exert immunosuppressive effects after rat liver transplantation. Compared with RAPA or mCAP alone, the combination of RAPA and mCAP could adequately reduce liver injury in rats with acute rejection after transplantation. The CD4+ T cell counts in peripheral blood, spleen, and transplanted liver of recipient rats significantly decreased, and the oxidative stress level and ferrous ion concentration of CD4+ T cells significantly increased in the combination group. In vitro, the combination of drugs significantly promoted autophagy, decreased GPX4 protein expression, and induced ferroptosis in CD4+ T cells. In conclusion, the autophagy inducer RAPA improved the mCAP-induced ferroptosis in CD4+ T cells. Our results support the concept of ferroptosis as an autophagy-dependent cell death and suggest that the combination of ferroptosis inducers and autophagy inducers is a new research direction for improving immunosuppressive regimens after liver transplantation.


Subject(s)
Carcinoma, Hepatocellular , Ferroptosis , Liver Neoplasms , Liver Transplantation , Humans , Rats , Animals , Sirolimus/therapeutic use , Sirolimus/pharmacology , T-Lymphocytes , Capecitabine/pharmacology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/surgery , Liver Neoplasms/drug therapy , Liver Neoplasms/surgery , Neoplasm Recurrence, Local , CD4-Positive T-Lymphocytes
18.
Transplantation ; 107(9): 1999-2008, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37607014

ABSTRACT

BACKGROUND: This study aimed to explore whether serum CXCL8 concentration can be used as a noninvasive marker of subclinical rejection (SCR) after pediatric liver transplantation (pLT). METHODS: Firstly, RNA sequencing (RNA-seq) was performed on 22 protocol liver biopsy samples. Secondly, several experimental methods were used to verify the RNA-seq results. Finally, the clinical data and serum samples of 520 LT patients in the Department of Pediatric Transplantation of Tianjin First Central Hospital from January 2018 to December 2019 were collected. RESULTS: RNA-seq results indicated that CXCL8 was significantly increased in the SCR group. The results of the 3 experimental methods were consistent with RNA-seq results. According to the 1:2 propensity score matching, 138 patients were divided into the SCR (n = 46) and non-SCR (n = 92) groups. Serological test results indicated that there was no difference in preoperative CXCL8 concentration between the SCR and non-SCR groups ( P > 0.05). However, during protocol biopsy, CXCL8 in the SCR group was significantly higher than in the non-SCR group ( P < 0.001). In diagnosing SCR, receiver operating characteristic curve analysis showed that the area under the curve of CXCL8 was 0.966 (95% confidence interval, 0.938-0.995), sensitivity was 95%, and specificity was 94.6%. In differentiating nonborderline from borderline rejection, the area under the curve of CXCL8 was 0.853 (95% confidence interval, 0.718-0.988), sensitivity was 86.7%, and specificity was 94.6%. CONCLUSIONS: This study demonstrates that serum CXCL8 concentration has high accuracy for the diagnosis and disease stratification of SCR after pLT.


Subject(s)
Liver Transplantation , Humans , Child , Liver Transplantation/adverse effects , Biopsy , Hospitals , Propensity Score , ROC Curve
19.
Bioact Mater ; 30: 98-115, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37560200

ABSTRACT

Peripheral nerve injuries may result in severe long-gap interruptions that are challenging to repair. Autografting is the gold standard surgical approach for repairing long-gap nerve injuries but can result in prominent donor-site complications. Instead, imitating the native neural microarchitecture using synthetic conduits is expected to offer an alternative strategy for improving nerve regeneration. Here, we designed nerve conduits composed of high-resolution anisotropic microfiber grid-cordes with randomly organized nanofiber sheaths to interrogate the positive effects of these biomimetic structures on peripheral nerve regeneration. Anisotropic microfiber-grids demonstrated the capacity to directionally guide Schwann cells and neurites. Nanofiber sheaths conveyed adequate elasticity and permeability, whilst exhibiting a barrier function against the infiltration of fibroblasts. We then used the composite nerve conduits bridge 30-mm long sciatic nerve defects in canine models. At 12 months post-implant, the morphometric and histological recovery, gait recovery, electrophysiological function, and degree of muscle atrophy were assessed. The newly regenerated nerve tissue that formed within the composite nerve conduits showed restored neurological functions that were superior compared to sheaths-only scaffolds and Neurolac nerve conduit controls. Our findings demonstrate the feasibility of using synthetic biophysical cues to effectively bridge long-gap peripheral nerve injuries and indicates the promising clinical application prospects of biomimetic composite nerve conduits.

20.
Polymers (Basel) ; 15(13)2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37447441

ABSTRACT

Continuous in vivo monitoring (CIVM) of pH value is essential for personalized medicine, as many diseases are closely related to acid-base imbalances. However, conventional pH meters are limited in their ability to perform CIVM due to excessive blood consumption, large device volume, frequent calibration, and inadequate real-time monitoring. There is thus an urgent need for a portable method for CIVM of pH value. To address this need, we propose a minimally invasive, continuous monitoring solution in the form of an implantable pH microneedle sensor (MNS) in this study. The MNS is based on the integration of an acupuncture needle (AN) and a Ag/AgCl reference electrode. We fabricate the sensor by electrochemically depositing platinum black and gold nanoparticles onto the AN and further modifying it with polyaniline to increase its sensitivity to hydrogen ions. The pH value is obtained by calculating the open circuit voltage between the modified AN and the reference electrode. The resulting MNS demonstrates excellent selectivity and a high nernstian response to pH (-57.4 mV per pH) over a broad range (pH = 4.0 to pH = 9.0). Both in vitro and in vivo experiments have verified the performance of the sensor, showcasing its potential for biomedical research and clinical practice. The MNS provides an alternative to conventional pH meters, offering a less invasive and more convenient way to perform CIVM of pH value. Moreover, this electrochemical implantable sensor based on AN and silver wires provides a simple and sensitive method for continuous in vivo detection of other biomarkers.

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