第8卷，第1期

ABO blood group-incompatible (ABOi) transplantation has been developed to overcome the serious problem of donor organ shortage. However, antibody-mediated rejection (ABMR) remains as the main limitation to successful ABOi transplantation. Introduction of desensitization treatment improved the outcomes of ABOi transplantation by suppressing ABMR; however, this strong, nonspecific immunosuppression also increases infectious complications. Recently, chimeric antigen receptor regulatory T cells (CAR Tregs) were developed to improve the antigen specificity, viability, and suppressive activity of Tregs. C4d deposition is a marker of ABMR and is also found in most ABOi allograft tissues. Based on these findings, we developed anti-C4d CAR Tregs to suppress ABMR in ABOi allografts. Anti-C4d CAR Tregs prepared by retroviral transduction of CAR into CD62L⁺CD4⁺CD25⁺ Tregs, expressed forkhead box P3 (Foxp3), CD25, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), latency-associated peptide (LAP), and glucocorticoid-induced tumor necrosis factor receptorrelated protein (GITR) to similar extents as nontransduced Tregs. Anti-C4d CAR Tregs were activated by specific binding to C4d and suppressed in vitro T cell proliferation as well as non-transduced Tregs. Furthermore, adoptive transfer of anti-C4d CAR Tregs significantly prolonged mouse ABOi heart allograft survival (P < 0.05).

1370

Cancer patients are at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mortality. Like other viruses in the SARS family, SARS-CoV-2 employs two host proteins, angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), for viral entry. Recent studies showed that many of the host proteins identified as potential targets for developing COVID therapies are dysregulated in cancer, prompting us to investigate whether human cancer cells are susceptible to SARS-CoV-2 infection, and whether chemotherapy could modulate a cancer patient's risk for infection.

1374

Interleukin-26 (IL-26), originally called AK155, is one of the cytokines of the IL-10 cytokine family, and its gene is located in human chromosome region 12q15. IL-26 signals through the receptors IL-20R1 and IL-10R2, which form a heterodimer, targets specific cells and induces activation of the JAK-STAT pathway, allowing the rapid phosphorylation of STAT1 and STAT3 and the initiation of their effects. This signaling plays an important role in the regulation of host defense and inflammatory diseases. However, whether the role of IL-26 in the progression of hepatocellular carcinoma (HCC) occurs via autophagy remains unclear. Here, we analyzed the association between IL-26 levels and the clinicopathological characteristics of 115 patients with HCC and found that IL-26 levels were particularly associated with tumor stage and survival. We found that IL-26 levels were associated with the prognosis of HCC patients. Furthermore, we found that increased autophagy by IL-26 was dependenton the JAK-STAT3 signaling pathway, which could result in the inhibition of the migration and invasion abilities of these HCC cells. These findings suggest that the levels of IL-26 may be a useful prognostic marker for HCC patients and may offer insights into the clinical application of IL-26 in the future.

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To defense harmful stimuli or maintain the immune homeostasis, the body produces and recruits a superfamily of cytokines such as interleukins, interferons, chemokines etc. Among them, chemokines act as crucial regulators in defense systems. CCL5/CCR5 combination is known for facilitating inflammatory responses, as well as inducing the adhesion and migration of different T cell subsets in immune responses. In addition, recent studies have shown that the interaction between CCL5 and CCR5 is involved in various pathological processes including inflammation, chronic diseases, cancers as well as the infection of COVID-19. This review focuses on how CCL5/CCR5 axis participates in the pathological processes of different diseases and their relevant signaling pathways for the regulation of the axis. Moreover, we highlighted the gene therapy and chemotherapy studies for treating CCR5-related diseases, including the ongoing clinical trials. The barriers and perspectives for future application and translational research were also summarized.

2999

The goal this review is to clarify the effects of the fat mass and obesity-associated protein (FTO) in lipid metabolism regulation and related underlying mechanisms through the FTO-mediated demethylation of m⁶A modification. FTO catalyzes the demethylation of m⁶A to alter the processing, maturation and translation of the mRNAs of lipid-related genes. FTO overexpression in the liver promotes lipogenesis and lipid droplet (LD) enlargement and suppresses CPT-1emediated fatty acid oxidation via the SREBP1c pathway, promoting excessive lipid storage and nonalcoholic fatty liver diseases (NAFLD). FTO enhances preadipocyte differentiation through the C/EBPb pathway, and facilitates adipogenesis and fat deposition by altering the alternative splicing of RUNX1T1, the expression of PPARg and ANGPTL4, and the phosphorylation of PLIN1, whereas it inhibits lipolysis by inhibiting IRX3 expression and the leptin pathway, causing the occurrence and development of obesity. Suppression of the PPARb/d and AMPK pathways by FTO-mediated m⁶A demethylation damages lipid utilization in skeletal muscles, leading to the occurrence of diabetic hyperlipidemia. m⁶A demethylation by FTO inhibits macrophage lipid influx by downregulating PPARg protein expression and accelerates cholesterol efflux by phosphorylating AMPK, thereby impeding foam cell formation and atherosclerosis development. In summary, FTO-mediated m⁶A demethylation modulates the expression of lipid-related genes to regulate lipid metabolism and lipid disorder diseases.

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Age-related macular degeneration (AMD) is a complex eye disorder and is the leading cause of incurable blindness worldwide in the elderly. Clinically, AMD initially affects the central area of retina known as the macula and it is classified as early stage to late stage (advanced AMD). The advanced AMD is classified into the nonexudative or atrophic form (dry AMD) and the exudative or neovascular form (wet AMD). More severe vision loss is typically associated with the wet form. Multiple genetic factors, lipid metabolism, oxidative stress and aging, play a role in the etiology of AMD. Dysregulation in genetic to AMD is established to 46%-71% of disease contribution, with CFH and ARMS2/HTRA1 to be the two most notable risk loci among the 103 identified AMD associated loci so far. Chronic cigarette smoking is the most proven consistently risk living habits for AMD. Deep learning algorithm has been developed based on image recognition to distinguish wet AMD and normal macula with high accuracy. Currently, anti-vascular endothelial growth factor (VEGF) therapy is highly effective at treating wet AMD. Several new generation AMD drugs and iPSC-derived RPE cell therapy are in the clinical trial stage and are promising to improve AMD treatment in the near future.

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Infections caused by viruses are one of the foremost causes of morbidity and mortality in the world. Although a number of antiviral drugs are currently used for treatment of various kinds of viral infection diseases, there is still no available therapeutic agent for most of the viruses in clinical practice. Coumarin is a chemical compound which is found naturally in a variety of plants, it can also be synthetically produced possessing diverse biological effects. More recently, reports have highlighted the potential role of coumarin derivatives as antiviral agents. This review outlines the advances in coumarin-based compounds against various viruses including human immunodeficiency virus, hepatitis virus, herpes simplex virus, Chikungunya virus and Enterovirus 71, as well as the structure activity relationship and the possible mechanism of action of the most potent coumarin derivatives.

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Glioblastoma (GBM) is one of the most aggressive (grade IV) gliomas characterized by a high rate of recurrence, resistance to therapy and a grim survival prognosis. The long-awaited improvement in GBM patients'survival rates essentially depends on advances in the development of new therapeutic approaches. Recent preclinical studies show that nanoscale materials could greatlycontributetotheimprovementofdiagnosisandmanagementofbraincancers. Inthecurrent review, we will discuss how specific features of glioma pathobiology can be employed for designing efficient targeting approaches. Moreover, we will summarize the main evidence for the potential of the IL-13R alpha 2 receptor (IL13a2R) targeting in GBM early diagnosis and experimental therapy.

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Melanoma is one of the most dangerous types of cutaneous neoplasms, which are pigment-producing cells of neuroectodermal origin found all over the body. A great deal of research is focused on the mechanisms of melanoma to promote better diagnostic and treatment options for melanoma in its advanced stages. The progression of melanoma involves alteration in different levels of gene expression. With the successful implementation of next-generation sequencing technology, an increasing number of long noncoding RNAs (lncRNAs) sequences have been discovered, and a significant number of them have phenotypic effects in both in vitro and in vivo studies, implying that they play an important role in the occurrence and progression of human cancers, particularly melanoma. A number of evidence indicated that lncRNAs are important regulators in tumor cell proliferation, invasion, apoptosis, immune escape, energy metabolism, drug resistance, epigenetic regulation. To better understand the role of lncRNAs in melanoma tumorigenesis, we categorize melanoma-associated lncRNAs according to their cellular functions and associations with gene expression and signaling pathways in this review. Based on the mechanisms of lncRNA, we discuss the possibility of lncRNA-target treatments, and the application of liquid biopsies to detect lncRNAs in melanoma diagnosis and prognosis.

1390

As key components of the ribosome and the most abundant RNA species, the rRNAs are modified during ribosome formation. N⁶-methyladenosine (m⁶A) is a conserved RNA modification occurring on different RNA species including rRNAs. Recently, it has been reported that ZCCHC4 and METTL5 are methyltransferases that mediate m⁶A modification of human 28S and 18S rRNA, respectively. The newly discovered biological functions of the two methyltransferases include regulation of mRNA translation, cell proliferation, cell differentiation, stress response, and other biological processes. Both of them, especially METTL5, have been proved to be associated with a variety of diseases such as intellectual disability, cancer, congenital dysplasia and have potential clinical application as biomarkers and therapeutic targets.

1288

Several types of modifications have been proven to participate in the metabolism and processing of different RNA types, including non-coding RNAs (ncRNAs). N-6-methyladenosine (m6A) is a dynamic and reversible RNA modification that is closely involved in the ncRNA homeostasis, and serves as a crucial regulator for multiple cancer-associated signaling pathways. The ncRNAs usually regulate the epigenetic modification, mRNA transcription and other biological processes, displaying enormous roles in human cancers. In this review, we summarized the significant implications of m6A-ncRNA interaction in various types of cancers. In particular, the interplay between m6A and ncRNAs in cancer pathogenesis and therapeutic resistance are being widely recognized. We also discussed the relevance of m6A-ncRNA interaction in immune regulation, followed by the interference on cancer immunotherapeutic procedures. In addition, we briefly highlighted the computation tools that could identify the accurate features of m6A methylome among ncRNAs. In summary, this review would pave the way for a better understanding of the biological functions of m6A-ncRNA crosstalk in cancer research and treatment.

1311

Chronic inflammation caused by persistent infections and metabolic disorders is thought to contribute to the increased cancer risk and the accelerated cancer progression. Oppositely, acute inflammation induced by bacteria-based vaccines or that is occurring after cancer selectively inhibits cancer progression and metastasis. However, the interaction between inflammation and cancer may be more complex than the current explanations for the relationship between chronic and acute inflammation and cancer. In this review, we described the impact of inflammation on cancer on the basis of three perspectives, including inflammation with different durations (chronic and acute inflammation), different scopes (systemic and local inflammation) and different occurrence sequences (inflammation occurring after and before cancer). In addition, we also introduced bacteria/virus-based cancer immunotherapies. We perceive that inflammation may be a double-edged sword with cancer-promoting and cancer-suppressing functions in certain cases. We expect to further improve the understanding of the relationship between inflammation and cancer and provide a theoretical basis for further research on their complex interaction.

1287

The mRNA polyadenylation plays essential function in regulation of mRNA metabolism. Mis-regulations of mRNA polyadenylation are frequently linked with aberrant gene expression and disease progression. Under the action of polyadenylate polymerase, poly (A) tail is synthesized after the polyadenylation signal (PAS) sites on the mRNAs. Alternative polyadenylation (APA) often occurs in mRNAs with multiple poly (A) sites, producing different 3′ ends for transcript variants, and therefore plays important functions in gene expression regulation. In this review, we first summarize the classical process of mRNA 3′-terminal formation and discuss the length control mechanisms of poly (A) in nucleus and cytoplasm. Then we review the research progress on alternative polyadenylation regulation and the APA site selection mechanism. Finally, we summarize the functional roles of APA in the regulation of gene expression and diseases including cancers.

1330

With the transformation of modern lifestyles and population ageing, obesity has become a global epidemic, as one of the important threat to human health of chronic non-communicable diseases (NCD). Stem cell therapy seems promising as an alternative strategy for managing obesity and related metabolic problems. Adipose tissue-derived stem cells (ADSCs) have received widespread attention, which provides new ideas for the treatment of obesity and various metabolic-related diseases, due to their abundant reserves, easy acquisition, rapid expansion, and multi-directional differentiation potential, low immunogenicity and many other advantages. Accordingly, there seems to be a "shield and spear paradox" in the relationship between ADSCs and obesity. In this review, we emphatically summarized the role of ADSCs in the occurrence and development of obesity and related metabolic disease processes, in order to pave the way for clinical practice.

1414

Germline heterozygous gain-of-function (GOF) mutation of NFKBIA, encoding IκBa, would affect the activation of NF-κB pathway and cause an autosomal dominant (AD) form of anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID). Here we reported a Chinese patient with a heterozygous N-terminal truncation mutation of NFKBIA/IκBa. She presented recurrent fever, infectious pneumonia and chronic diarrhea with EDA-ID. Impaired NF-κB translocation and IL1R and TLR4 pathway activation were revealed in this patient. The findings suggested that the truncation mutation of IκBa caused medium impaired of activation of NF-κB but the early death. Furthermore, we reviewed all the reported patients with NFKBIA mutation to learn more about this disease.

1274

TSC renal cystic disease is poorly understood and has no approved treatment. In a new principal cell-targeted murine model of Tsc cystic disease, the renal cystic epithelium is mostly composed of type A intercalated cells with an intact Tsc2 gene confirmed by sequencing, although these cells exhibit a Tsc-mutant disease phenotype. We used a newly derived targeted murine model in lineage tracing and extracellular vesicle (EV) characterization experiments and a cell culture model in EV characterization and cellular induction experiments to understand TSC cystogenesis. Using lineage tracing experiments, we found principal cells undergo clonal expansion but contribute very few cells to the cyst. We determined that cystic kidneys contain more interstitial EVs than noncystic kidneys, excrete fewer EVs in urine, and contain EVs in cyst fluid. Moreover, the loss of Tsc2 gene in EV-producing cells greatly changes the effect of EVs on renal tubular epithelium, such that the epithelium develops increased secretory and proliferative pathway activity. We demonstate that the mTORC1 pathway activity is independent form the EV production, and that the EV effects for a single cell line can vary significantly. TSC cystogenesis involves significant contribution from genetically intact cells conscripted to the mutant phenotype by mutant cell derived EVs.

1245

Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disorder worldwide. Murine models of NAFLD have been widely used to explore its pathogenesis. In this study, we performed a systematic evaluation of hepatic genome-wide mRNA expression by RNA-Sequencing using three mouse models of NAFLD: leptin receptor deficient db/db mice, high-fat high-sugar diet (HSHF) -induced obese mice, and dexamethasone (DEX) -induced NAFLD mice. As a result, we found both distinct and common pathways in the regulation of lipid metabolism from transcriptomes of three mouse models. Moreover, only a total of 12 differentially expressed genes (DEGs) were commonly detected among all three mouse groups, indicating very little overlap among all three models. Therefore, our results suggest that NAFLD is a heterogeneous disease with highly variable molecular mechanisms.

1272

Nasopharyngeal carcinoma (NPC) is a common malignant carcinoma of the head and neck, and the biological mechanisms underlying the pathogenesis of NPC remain not fully understood. In the present study, we systematically analyzed four independent NPC transcriptomic datasets and focused on identifying the critical molecular networks and novel key hub genes implicated in NPC. We found totally 170 common overlapping differentially expressed genes (DEGs) in the four NPC datasets. GO and KEGG pathway analysis revealed that cell cycle dysregulation is a critical event in NPC. Protein-protein interaction (PPI) network analysis identified a 15 hub-gene core network with overexpressed kinesin family member 2C (KIF2C) as a central regulator. Loss-of-function study demonstrated that knockdown of KIF2C signif icantly inhibited cell growth and cell motility, and delayed cell cycle progression, accompanied with dramatic mitotic defects in spindle formation in NPC cells. RNA-seq analysis revealed that KIF2C knockdown led to deregulation of various downstream genes. KIF2C could also regulate the AKT/mTOR pathways, and enhance paclitaxel sensitivity in NPC cells. Taken together, our results suggest that cell cycle dysregulation is a critical event during NPC pathogenesis andKIF2C is a novel key mitotic hub gene with therapeutic potential in NPC.

1529

Despite the growing knowledge of T cell responses in COVID-19 patients, there is a lack of detailed characterizations for T cell-antigen interactions and T cell functions. Here, with a predicted peptide library from SARS-CoV-2 S and N proteins, we found that specific CD8⁺ T cell responses were identified in over 75% of COVID-19 convalescent patients (15/20) and an epitope from the N protein, N^361-369 (KTFPPTEPK), was the most dominant epitope from our selected peptide library. Importantly, we discovered 2 N^361-369-specific T cell receptors (TCRs) with high functional avidity that were independent of the CD8 co-receptor. These TCRs exhibited complementary cross-reactivity to several presently reported N^361-369 mutant variants, as to the wild-type epitope. Further, the natural functions of these TCRs in the cytotoxic immunity against SARS-CoV-2 were determined with dendritic cells (DCs) and the lung organoid model. We found that the N^361-369 epitope could be normally processed and endogenously presented by these different types of antigen presenting cells, to elicit successful activation and effective cytotoxicity of CD8⁺ T cells ex vivo. Our study evidenced potential mechanisms of cellular immunity to SARS-CoV-2, and illuminated potential ways of viral clearance in COVID-19 patients. These results indicate that utilizing CD8-independent TCRs against SARS-CoV-2-associated antigens may provide functional superiority that is beneficial for the adoptive cell immunotherapies based on natural or genetically engineered T cells. Additionally, this information is highly relevant for the development of the next-generation vaccines with protections against continuously emerged SARS-CoV-2 mutant strains.

1441

Filopodia, a finger-like structure and actin-rich plasma-membrane protrusion at the leading edge of the cell, has important roles in cell motility. However, the mechanisms of filopodia generation are not well-understood via the actin-related protein 2/3 (ARP2/3) complex in Non-Small Cell Lung Cancer (NSCLC) cells. We previously have demonstrated that PRR11 associates with the ARP2/3 complex to regulate cytoskeleton-nucleoskeleton assembly and chromatin remodeling. In this study, we further demonstrate that PRR11 involves in filopodia formation, focal adhesion turnover and cell motility through ARP2/3 complex. Cell phenotype assays revealed that the silencing of PRR11 increased cellular size and inhibited cell motility in NSCLC cells. Mechanistically, PRR11 recruited and co-localized with Arp2 at the membrane protrusion to promote filopodia formation but not lamellipodia formation. Notably, PRR11 mutant deletion of the proline-rich region 2 (amino acid residues 185-200) abrogated the effect of filopodia formation. In addition, PRR11-depletion inhibited filopodial actin filaments assembly and increased the level of active integrin b1 in the cell surface, whereas reduced the phosphorylation level of focal adhesion kinase (FAK^Y397) to repress focal adhesion turnover and cell motility in NSCLC cells. Taken together, our findings indicate that PRR11 has critical roles in controlling filopodia formation, focal adhesion turnover and cell motility by recruiting ARP2/ 3 complex, thus dysregualted expression of PRR11 potentially facilitates tumor metastasis in NSCLC cells.

1322

It is increasingly aware that gut microbiota is closely associated with atherosclerosis. However, which and how specific gut bacteria regulate the progression of atherosclerosis is still poorly understood. In this study, modified linear discriminant analysis was performed in comparing the gut microbiota structures of atherosclerotic and non-atherosclerotic mice, and Desulfovibrio desulfuricans (D. desulfuricans) was found to be associated with atherosclerosis.D. desulfuricans-treated Apoe^-/-mice showed significantly aggravated atherosclerosis. The proatherogenic effect of D. desulfuricans was attributed to its ability to increase intestinal permeability and subsequent raise in the transit of lipopolysaccharide (LPS) from the intestine to the bloodstream. Excessive LPS in the blood can elicit local and systemic inflammation and activate Toll-like receptor 4 (TLR4) /nuclear factor-κB (NF-κB) signaling of endothelial cells. TAK-242, a specific inhibitor of TLR4, can ameliorate the development of D. desulfuricans-induced atherosclerosis by blocking the LPS-induced activation of TLR4/NF-κB signaling.

1351

SARS-CoV-2 virus is responsible for the current worldwide coronavirus disease 2019 (COVID-19) pandemic, infecting millions of people and causing hundreds of thousands of deaths. Understanding the antibody response to SARS-CoV-2 is crucial for the development of vaccines, therapeutics and public health interventions. However, lack of consistency in methods used to monitor antibody response to SARS-CoV-2 leaves some uncertainty in our fine understanding of the human antibody response mounted following SARS-CoV-2 infection. We developed a peptide-based enzyme-linked immunosorbent assay (ELISA) by selecting 7 synthetic peptides from the spike, membrane, and nucleocapsid protein sequences of SARS-CoV-2, which effectively detects the antibody response mounted by all COVID-19 convalescent tested. Strikingly, the assay shows a profound difference in antibody response among individual subjects, which may have a significant impact on disease severity. Together, our results define an efficient and specific serological assay to consistently measure the antibody response following SARS-CoV-2 infection, as well as help the design of vaccine and therapeuticals for prevention and treatment of COVID-19.

1585

Osteoporosis (OP) is a debilitating skeletal abnormality involving bone remodeling and bone cell homeostasis characterized by decreased bone strength and high fracture risk. A novel therapeutic intervention for OP by manipulating cellular autophagy-apoptosis processes to promote skeletal homeostasis is presented. Protective effects of the naturally occurring plant extract Liquiritigenin (LG) were demonstrated in an ovariectomy (OVX) -OP mouse model and preosteoblast MC3T3-E1 cells. Micro-CT and histological staining assessments of skeletal phenotype were applied alongside detection of autophagy activity in osteocytes and MC3T3-E1 cells by transmission electron microscopy (TEM). The effects of LG on chloroquine (CQ) -and the apoptosis-inducing TS-treated osteogenic differentiations and status of lysosomes within MC3T3-E1 cells were analyzed by Neutral red, Alizarin red S and alkaline phosphatase (ALP) staining and Western blot assays. Treatment with LG prevented bone loss, increased osteogenic differentiation in vivo and in vitro, and inhibited osteoclast formation to some extent. TEM analyses revealed that LG can improve auto-lysosomal degradation within osteocytes from OVX mice and MC3T3-E1 cells. The abnormal status of lysosomes associated with CQ and TS treatments was notably alleviated by LG which also reduced levels of apoptosis-induced inhibition of osteogenic differentiation and averted abnormal osteogenic differentiation as a consequence of a blockage in autolysosome degradation. Overall, LG stimulates bone growth in OVX mice through increased osteogenic differentiation and regulation of autophagy-apoptosis mechanisms, presenting an auspicious natural therapy for OP.

1449

After publication of the article, the authors recently noticed unintentional errors in Figure 6. Three pairs of sub figures contain misplaced and identical images due to unintentional errors during the preparation of the relevant Figures for publication: (1) Figure 3C, upper panel, lane 3 (CD79a, IgM-group) vs. Figure 6A, lower panel, lane 1 (CCND1, CD19-/IgM-group); (2) Figure 3C, upper panel, lane 6 (CD79a, IgM + group) vs. Figure 6B, lower panel, lane 3 (CCND1, CD19+/IgM + group); (3) Figure 6C (ii), upper panel, lane 4 (IgM) vs. lane 5 (Pax5). Nevertheless, the unintentional errors do not change the conclusion or discussion of the article. The authors apologize for any inconvenience caused by these unintentional errors.

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