Emerging delivery strategy for oncolytic virotherapy.

Oncolytic virotherapy represents a promising approach in cancer immunotherapy. The primary delivery method for oncolytic viruses (OVs) is intratumoral injection, which apparently limits their clinical application. For patients with advanced cancer with disseminated metastasis, systemic administration is considered the optimal approach. However, the direct delivery of naked viruses through intravenous injection presents challenges, including rapid clearance by the immune system, inadequate accumulation in tumors, and significant side effects. Consequently, the development of drug delivery strategies has led to the emergence of various bio-materials serving as viral vectors, thereby improving the anti-tumor efficacy of oncolytic virotherapy. This review provides an overview of innovative strategies for delivering OVs, with a focus on nanoparticle-based or cell-based delivery systems. Recent pre-clinical and clinical studies are examined to highlight the enhanced efficacy of systemic delivery using these novel platforms. In addition, prevalent challenges in current research are briefly discussed, and potential solutions are proposed.

Genome-wide profiling of histone acetylation enhancer of fatty liver hemorrhagic syndrome in laying hens.

Objective: Rare study of the non-coding and regulatory regions of the genome limits our ability to decode the mechanisms of fatty liver hemorrhage syndrome (FLHS) in chickens. Method: Herein, we constructed the HFD-induced FLHS chicken model to investigate the genome-wide active enhancers and transcriptome by H3K27ac target chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-Seq) profiles of normal and FLHS liver tissues. Concurrently, an integrative analysis combining ChIP-seq with RNA-Seq and a comparative analysis with chicken FLHS, rat Non-alcoholic fatty liver disease (NAFLD) and human NAFLD at the transcriptome level revealed the enhancer target genes and conservative genes involved in metabolic processes. Results: In total, 56 and 199 peak-genes were identified in upregulated peak-genes positively regulated by H3K27ac (Cor (peak-gene correlation) ≥ 0.5 & log2(FoldChange) ≥ 1) (PP) and downregulated peak-genes positively regulated by H3K27ac (Cor (peak-gene correlation) ≥ 0.5 & log2(FoldChange) ≤ -1)(PN), respectively; then we screened key regulatory targets mainly distributing in lipid metabolism (PCK1, APOA4, APOA1, INHBE) and apoptosis (KIT, NTRK2) together with MAPK and PPAR signaling pathway in FLHS. Intriguingly, PCK1 was also significantly covered in up-regulated super-enhancers (SEs), which further implied the vital role of PCK1 during the development of FLHS. Conclusion: Together, our studies provided new insights into the pathogenesis and potential therapy biomarkers of FLHS.

Loss of LBP triggers lipid metabolic disorder through H3K27 acetylation-mediated C/EBPß- SCD activation in non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is associated with mutations in lipopolysaccharide-binding protein ( LBP), but the underlying epigenetic mechanisms remain understudied. Herein, LBP -/- rats with NAFLD were established and used to conduct integrative targeting-active enhancer histone H3 lysine 27 acetylation (H3K27ac) chromatin immunoprecipitation coupled with high-throughput and transcriptomic sequencing analysis to explore the potential epigenetic pathomechanisms of active enhancers of NAFLD exacerbation upon LBP deficiency. Notably, LBP -/- reduced the inflammatory response but markedly aggravated high-fat diet (HFD)-induced NAFLD in rats, with pronounced alterations in the histone acetylome and regulatory transcriptome. In total, 1 128 differential enhancer-target genes significantly enriched in cholesterol and fatty acid metabolism were identified between wild-type (WT) and LBP -/- NAFLD rats. Based on integrative analysis, CCAAT/enhancer-binding protein ß (C/EBPß) was identified as a pivotal transcription factor (TF) and contributor to dysregulated histone acetylome H3K27ac, and the lipid metabolism gene SCD was identified as a downstream effector exacerbating NAFLD. This study not only broadens our understanding of the essential role of LBP in the pathogenesis of NAFLD from an epigenetics perspective but also identifies key TF C/EBPß and functional gene SCD as potential regulators and therapeutic targets.

Role of exosomes in metastasis and therapeutic resistance in esophageal cancer.

Esophageal cancer (EC) has a high incidence and mortality rate and is emerging as one of the most common health problems globally. Owing to the lack of sensitive detection methods, uncontrollable rapid metastasis, and pervasive treatment resistance, EC is often diagnosed in advanced stages and is susceptible to local recurrence. Exosomes are important components of intercellular communication and the exosome-mediated crosstalk between the cancer and surrounding cells within the tumor microenvironment plays a crucial role in the metastasis, progression, and therapeutic resistance of EC. Considering the critical role of exosomes in tumor pathogenesis, this review focused on elucidating the impact of exosomes on EC metastasis and therapeutic resistance. Here, we summarized the relevant signaling pathways involved in these processes. In addition, we discussed the potential clinical applications of exosomes for the early diagnosis, prognosis, and treatment of EC.

Development of cancer-associated fibroblast-related gene signature for predicting the survival and immunotherapy response in lung adenocarcinoma.

The present study aims to construct a predictive model for prognosis and immunotherapy response in lung adenocarcinoma (LUAD). Transcriptome data were extracted from the Cancer Genome Atlas (TCGA), GSE41271, and IMvigor210. The weighted gene correlation network analysis was utilized to identify the hub modules related to immune/stromal cells. Then, univariate, LASSO, and multivariate Cox regression analyses were employed to develop a predictive signature based on genes of the hub module. Moreover, the association between the predictive signature and immunotherapy response was also investigated. As a result, seven genes (FGF10, SERINE2, LSAMP, STXBP5, PDE5A, GLI2, FRMD6) were screened to develop the cancer associated fibroblasts (CAFs)-related risk signature (CAFRS). LUAD patients with high-risk score underwent shortened Overall survival (OS). A strong correlation was found between CAFRS and immune infiltrations/functions. The gene set variation analysis showed that G2/M checkpoint, epithelial-mesenchymal transition, hypoxia, glycolysis, and PI3K-Akt-mTOR pathways were greatly enriched in the high-risk subgroup. Moreover, patients with higher risk score were less likely to respond to immunotherapy. A nomogram based on CAFRS and Stage presented a stronger predictive performance for OS than the single indicator. In conclusion, the CAFRS exhibited a potent predictive value for OS and immunotherapy response in LUAD.

Live-attenuated Japanese encephalitis virus inhibits glioblastoma growth and elicits potent antitumor immunity.

Glioblastomas (GBMs) are highly aggressive brain tumors that have developed resistance to currently available conventional therapies, including surgery, radiation, and systemic chemotherapy. In this study, we investigated the safety of a live attenuated Japanese encephalitis vaccine strain (JEV-LAV) virus as an oncolytic virus for intracerebral injection in mice. We infected different GBM cell lines with JEV-LAV to investigate whether it had growth inhibitory effects on GBM cell lines in vitro. We used two models for evaluating the effect of JEV-LAV on GBM growth in mice. We investigated the antitumor immune mechanism of JEV-LAV through flow cytometry and immunohistochemistry. We explored the possibility of combining JEV-LAV with PD-L1 blocking therapy. This work suggested that JEV-LAV had oncolytic activity against GBM tumor cells in vitro and inhibited their growth in vivo. Mechanistically, JEV-LAV increased CD8+ T cell infiltration into tumor tissues and remodeled the immunosuppressive GBM microenvironment that is non-conducive to immunotherapy. Consequently, the results of combining JEV-LAV with immune checkpoint inhibitors indicated that JEV-LAV therapy improved the response of aPD-L1 blockade therapy against GBM. The safety of intracerebrally injected JEV-LAV in animals further supported the clinical use of JEV-LAV for GBM treatment.

Optimization of deposition process for a productive and cohesive bio-CaCO3 to repair concrete existing cracks.

Microbial-induced carbonate precipitation (MICP) is being investigated to repair concrete cracks because of its good durability and compatibility with cementitious matrix. However, during the in-situ application, the repairing often lasts weeks, even months. And the strength regain is quite low. The repairing time is largely determined by the CaCO3 yield, and the strength regain after the repair is closely related to the cohesion and bonding strength of CaCO3 itself. Thus, the purpose of this paper is to obtain an efficient precipitation of bio-CaCO3 with both high yield and good cohesion to improve the in-situ repairing efficiency. Firstly, the most influential factors on urease activity were screened and the precipitation kinetics were detailly investigated. The results show that the CaCO3 with the largest yield and cohesion was obtained when the bacterial concentration was 107 cells/mL and the concentration of urea and calcium was both 0.5 M at 20 °C. This weight loss of bio-CaCO3 was 9.24% under ultrasonic attack. Secondly, two models were established to quantify or semi-quantify the relationship between the most influential factors and the yield and cohesion of precipitates, respectively. The results showed the order of contribution for bio-CaCO3 precipitation was calcium ions concentration > bacterial concentration > urea concentration > temperature > initial pH. According to these models, the required yield and cohesion of CaCO3 by engineering could be obtained by adjusting affecting factors. Models were proposed for guiding the application of MICP in practical engineering. KEY POINTS: • Screened the most affecting factors on urease activity and investigated the precipitation kinetics. • Obtained optimal conditions of bio-CaCO. • Established two models in order to give some guidance for practical civil engineering.

Comparative physiological and soil microbial community structural analysis revealed that selenium alleviates cadmium stress in Perilla frutescens.

Cadmium (Cd) toxicity not only affects plant growth and development, but also affects human health through the food chain. Several studies have demonstrated that Selenium (Se) alleviates Cd stress in plants; however, whether and how Se-alleviated Cd stress by regulating the structure of soil microbial community remain largely unclear. Here, we investigated the alleviating effects of exogenous applied Se (foliar spraying or root application) on plant growth under Cd stress in perilla (Perilla frutescens L.) by measuring the biomass, photosynthetic fluorescence parameters, root cell wall components and soil microbial community structure and diversity. Under Cd stress, perilla seedlings supplemented with Se increased chlorophyll content. Foliar spraying Se increased the levels of relative chlorophyll content (ΦII), photosynthetic system II (ΦPSII) and electron transport rate (ETR) in perilla leaves under Cd stress; while, root application of Se increased the levels of photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), water use efficiency (WUE) and stomatal limitation value (Ls) under Cd stress. Compared with Cd toxicity alone, root application of Se increased the contents of hemicellulosic 1 and hemicellulosic 2 in the cell wall of perilla roots. Cd toxicity or root application of Se did not affect soil bacterial community diversity. Root application of Se increased the relative abundance of Proteobacteria, Bacteroidetes, Fibrobacteres, Sphingomonas and Nitrosospira in Cd-contaminated soil, and thereby improving soil microbial community structure, finally promoting the growth of perilla seedlings.

In Situ Tumor Vaccine Expressing Anti-CD47 Antibody Enhances Antitumor Immunity.

In situ tumor vaccine is a potential cancer therapy due to their advantages in induction of antitumor immune responses. Oncolytic virotherapy utilizes natural or engineered oncolytic viruses to kill tumors selectively, representing a promising in situ tumor vaccine for cancer immunotherapy. In addition to direct oncolysis, oncolytic viruses elicit potent and durable antitumor immune responses by induction of immunogenic cell death of tumors. Membrane protein CD47 overexpressed on tumor cells engages in "don't eat me" signal that prevents macrophages from engulfing tumor cells. CD47-targeting agents have been tested via preclinical and clinical trials. As potential tumor vaccine vectors, oncolytic viruses can be engineered to express anti-CD47 antibodies to induce potentiated tumor killing. Therefore, we developed an adenovirus-based tumor vaccine loaded with a CD47-targeting nanobody fused with the IgG2a Fc protein. B16-F10 melanoma, A20 lymphoma, and 4T1 breast cancer models in immunocompetent mice were established to evaluated in vivo antitumor efficacy of in situ tumor vaccination. The tumor vaccine armed with a nanobody against CD47 induced durable suppression of the tumor and long-term survival of tumor-bearing mice, and also elevated the number of tumor-infiltrating immune cells with an activated immunophenotype, suggesting that it could remodel the tumor immune microenvironment. Systemic antitumor effects and immune memory were also observed in immunocompetent mice following in situ vaccination with the anti-CD47 tumor vaccines; tumorigenesis was completely inhibited in these mice after tumor re-challenge. The recombinant anti-CD47 tumor vaccine has an effectual antitumor activity and may be a promising antitumor agent.

Identification of human LDHC4 as a potential target for anticancer drug discovery.

One of the distinct hallmarks of cancer cells is aerobic glycolysis (Warburg effect). Lactate dehydrogenase A (LDHA) is thought to play a key role in aerobic glycolysis and has been extensively studied, while lactate dehydrogenase C (LDHC), an isoform of LDHA, has received much less attention. Here we showed that human LDHC was significantly expressed in lung cancer tissues, overexpression of Ldhc in mice could promote tumor growth, and knock-down of LDHC could inhibit the proliferation of lung cancer A549 cells. We solved the first crystal structure of human LDHC4 and found that the active-site loop of LDHC4 adopted a distinct conformation compared to LDHA4 and lactate dehydrogenase B4 (LDHB4). Moreover, we found that (ethylamino) (oxo)acetic acid shows about 10 times selective inhibition against LDHC4 over LDHA4 and LDHB4. Our studies suggest that LDHC4 is a potential target for anticancer drug discovery and (ethylamino) (oxo)acetic acid provides a good start to develop lead compounds for selective drugs targeting LDHC4.

Long noncoding RNA RP11-241J12.3 targeting pyruvate carboxylase promotes hepatocellular carcinoma aggressiveness by disrupting pyruvate metabolism and the DNA mismatch repair system.

Accumulating evidence indicates that hepatitis B virus X protein (HBx) plays a key role in HBV-related hepatocellular carcinoma (HCC) aggressiveness; however, the underlying mechanisms are not entirely clear. Long non-coding RNAs (lncRNAs), which participate in the regulation of diverse biological processes, may be critical for the function of HBx. Our research indicated that HBx induced changes in the expression of numerous lncRNAs and implicated the novel lncRNA RP11-241J12.3 in HBx-mediated HCC aggressiveness. Although RP11-241J12.3 expression was downregulated in transient HBx-expressing HCC cells (similar to the early stage of HBV infection), its oncogenic properties remained. The results showed that RP11-241J12.3 not only accelerated DNA synthesis and upregulated the expression of pyruvate carboxylase (PC) and MSH3, which is a key protein in pyruvate metabolism and DNA mismatch repair (MMR), but also promoted tumor growth in vitro and in vivo, thus promoting HCC aggressiveness. More importantly, we revealed that RP11-241J12.3 may interact with PC and identified its location in the cytoplasm close to the nucleus using fluorescence in situ hybridization (FISH). We also observed RP11-241J12.3 expression was upregulated in HCC tissues compared with the paracarcinomatous tissues. Furthermore, RP11-241J12.3 expression levels showed a close relationship with clinical stage and tumor size and that low RP11-241J12.3 expression was significantly correlated with longer HCC patient survival. These results further our understanding of the lncRNAs regulated by HBx in HCC, and provide evidence that dysregulation of RP11-241J12.3 contributes to HCC aggressiveness.

Epigenetic association study uncovered H3K27 acetylation enhancers and dysregulated genes in high-fat-diet-induced nonalcoholic fatty liver disease in rats.

Aim: To evaluate the regulatory landscape underlying the active enhancer marked by H3K27ac in high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) in rats. Materials & methods: H3K27ac chromatin immunoprecipitation and high-throughput RNA sequencing to construct regulatory profiles and transcriptome of liver from NAFLD rat model induced by HFD. De novo motif analysis for differential H3K27ac peaks. Functional enrichment, Kyoto Encyclopedia of Genes and Genomes pathway and protein-protein interaction network were examined for differential peak-genes. The mechanism was further verified by western blot, chromatin immunoprecipitation-quantitative PCR and real-time PCR. Results: A total of 1831 differential H3K27ac peaks were identified significantly correlating with transcription factors and target genes (CYP8B1, PLA2G12B, SLC27A5, CYP7A1 and APOC3) involved in lipid and energy homeostasis. Conclusion: Altered acetylation induced by HFD leads to the dysregulation of gene expression, further elucidating the epigenetic mechanism in the etiology of NAFLD.

What is this summary about? Nonalcoholic fatty liver disease (NAFLD) is a typical metabolic disease, which is becoming the most common liver disease in the world. Despite its high prevalence and morbidity, there is currently no effective diagnostic or approved therapy, and the molecular mechanisms for NAFLD have not been fully clarified, especially for epigenetics. Herein, we focused on histone modification and investigated the impact of active enhancer to explore the epigenetic regulation of NAFLD, seeking new targets for the prevention and treatment of the disease. What were the results? We identified the alteration of H3K27 acetylation and differential gene expression, enriched potential transcription-factor binding motifs and highlighted the hub risk genes of CYP8B1, PLA2G12B, SLC27A5, CYP7A1 and APOC3 in a NAFLD rat model. What do the results mean? This work emphasized the vital roles of histone modification of H3K27ac in a high-fat-diet-induced NAFLD model, which could regulate the expression of key genes and transcription factor binding motifs, and H3K27ac induced the formation of NAFLD. Targeting the H3K27ac modification, dysregulated target genes and enriched pathways may be of great importance for NAFLD prediction and prevention, and serve as a valuable resource for genome-wide studies of epigenomic regulation in lipid metabolic disease.

High-dose VitC plus oncolytic adenoviruses enhance immunogenic tumor cell death and reprogram tumor immune microenvironment.

Preclinical and clinical studies have validated the antitumor effects of several oncolytic viruses (OVs). However, the efficacy of OVs is limited when they are administered as monotherapies. Combination therapy is a promising direction for oncolytic virotherapy in the future. A high dose of vitamin C (VitC) exerts anticancer effects by triggering the accretion of substantial amounts of reactive oxygen species (ROS). OVs can induce immunogenic tumor cell death and elicit an antitumor immune response. ROS play an important role in immunogenic cell death (ICD). This study aimed to explore whether high-dose VitC in combination with oncolytic adenoviruses (oAds) exhibited a synergistic antitumor effect. High-dose VitC synergized with oAds against tumor by enhancing immunogenic tumor cell death. Combination therapy with high-dose VitC and oAds significantly increased the number of T cells in the tumor microenvironment (TME) and promoted the activation of T cells. Furthermore, the antitumor effect of the combination therapy was CD8+ T cell dependent. In addition, combination therapy with high-dose VitC and oAds reprogramed the immunosuppressive TME. Our study provides a new strategy for combination therapy of OVs.

Antifibrotic Therapy Augments the Antitumor Effects of Vesicular Stomatitis Virus Via Reprogramming Tumor Microenvironment.

Solid tumors are characterized by abundant extracellular matrix originating from cancer-associated fibroblasts (CAFs). High collagen content can trigger the collapse of vascular system in the tumor and form physical barrier that eventually impedes the penetration of drug particles and cytotoxic immune cells. Moreover, CAFs is able to promote the enrichment of tumor-associated macrophages (TAMs) and differentiation of myeloid-derived suppressor cells (MDSCs) that work in concert to develop a highly immunosuppressive tumor microenvironment (TME). In this study, we investigated if halofuginone, an antifibrotic drug, can augment the therapeutic effects of oncolytic vesicular stomatitis virus (VSV). The results revealed that halofuginone significantly disrupts the collagen network in tumors and promotes the distribution of VSV and infiltration of CD8+ T cells (p < 0.0001). Combined treatment of VSV and halofuginone also modulates the immunosuppressive TME via deletion of TAM, MDSCs, and regulatory T cells (Tregs). Collectively, the combination therapy remarkably inhibits the tumor growth in multiple murine models and prolongs survival of mice. The results demonstrate the clinical potential of halofuginone in combination with oncolytic virus.

Oncolytic adenovirus inhibits malignant ascites of advanced ovarian cancer by reprogramming the ascitic immune microenvironment.

Malignant ascites frequently occur in patients with advanced ovarian cancer at initial diagnosis, and in almost all cases of relapse, they are closely related to poor prognosis, chemoresistance, and metastasis. To date, effective management strategies have been limited. In this study, we aimed to investigate the effects of oncolytic adenovirus (OV) on malignant ascites in a mouse model of advanced ovarian cancer. The results suggested that OV conferred an effective ability to reduce ascites development and prolong overall survival. Further analysis of the ascitic immune microenvironment revealed that OV treatment promoted T cell infiltration, activation, and differentiation into the effector phenotype; reprogrammed macrophages toward the M1-like phenotype; and increased the ratios of both CD8+ T cells to CD4+ T cells and M1 to M2 macrophages. However, immunosuppressive factors such as PD-1, LAG-3, and Tregs emerged after treatment. Combination therapy including OV, CSF-1R inhibitor PLX3397, and anti-PD-1 remarkably delayed the progression of ascites, and combination therapy induced a greater extent of T cell infiltration, proliferation, and activation. This study provides experimental and theoretical evidence for oncolytic virus-based treatment of malignant ascites, which may further contribute to advanced ovarian cancer therapy.

Engineered exosome-like nanovesicles suppress tumor growth by reprogramming tumor microenvironment and promoting tumor ferroptosis.

Tumor vaccines that induce effective and sustained antitumor immunity are highly promising for cancer therapy. However, the antitumor potential of these vaccines is weakened due to the immunosuppressive characteristics of the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are the most abundant stromal cells within the TME; they play an important role in tumor growth, metastasis, immunosuppression, and drug resistance. Fibroblast activation protein-α (FAP) is overexpressed in CAFs in more than 90% of human tumor tissues. Further, FAP+CAFs are an ideal interstitial target for the immunotherapy of solid tumors. Exosomes derived from tumor cells contain many tumor antigens, which can be used as the basis of tumor vaccines that elicit strong antitumor immunity. Almost all exosome-based cancer vaccines have been designed and developed for tumor parenchymal cells. Moreover, the exosome production is very low and the purification is very difficult, limiting their clinical application as tumor vaccines. In this study, we developed FAP gene-engineered tumor cell-derived exosome-like nanovesicles (eNVs-FAP) as a tumor vaccine that can be prepared easily and in large quantities. The eNVs-FAP vaccine inhibited tumor growth by inducing strong and specific cytotoxic T lymphocyte (CTL) immune responses against tumor cells and FAP+CAFs and reprogramming the immunosuppressive TME in the colon, melanoma, lung, and breast cancer models. Moreover, eNVs-FAP vaccine-activated cellular immune responses could promote tumor ferroptosis by releasing interferon-gamma (IFN-γ) from CTLs and depleting FAP+CAFs. Thus, eNVs-FAP is a candidate tumor vaccine targeting both the tumor parenchyma and the stroma. STATEMENT OF SIGNIFICANCE: Nanovaccines can activate immune cells and promote an antitumor immune response. In this study, we developed the fibroblast activation protein-α (FAP) gene-engineered tumor cell-derived exosome-like vesicle vaccines (eNVs-FAP). A large number of eNVs-FAP were obtained by continuously squeezing FAP gene-engineered tumor cells. eNVs-FAP showed excellent antitumor effects in a variety of tumor-bearing mouse models. The mechanistic analysis showed that eNVs-FAP promoted the maturation of dendritic cells (DCs), increased the infiltration of effector T cells into target tumor cells and FAP-positive cancer-associated fibroblasts (FAP+CAFs), and reduced the proportion of immunosuppressive cells, including M2-like tumor-associated macrophages (M2-TAMs), myeloid-derived suppressor cells (MDSCs), and regulatory T cells (Tregs), in the tumor microenvironment (TME). Moreover, the clearance of FAP+CAFs helped enhance interferon-gamma-induced tumor cell ferroptosis.

The Effect of Residual Triton X-100 on Structural Stability and Infection Activity of Adenovirus Particles.

To ensure the high purity and biological activity of the adenovirus vector to be used for clinical applications, a stable and linearly scalable preparation method is highly imperative. During the adenovirus-harvesting process, the Triton X-100-based lysis method possesses the advantages of higher efficiency as well as easier linearization and amplification. Most Triton X-100 can be removed from the adenovirus sample by chromatographic purification. However, there is no report that a small amount of residual Triton X-100, present in adenovirus sample, can affect the particle integrity, infectivity, and structure of adenoviruses. Here, we found that although residual Triton X-100 affected the short-term stability, purity, infectivity, and structure of adenoviruses at 37°C, it did not hamper these properties of adenoviruses at 4°C. This study suggests that although the Triton X-100-based lysis method is a simple, efficient, and easy-to-scale process for lysing host cells to release the adenovirus, the storage conditions of adenovirus products must be taken into consideration.

The leaf extract of crofton weed (Eupatorium adenophorum) inhibits primary root growth by inducing cell death in maize root border cells.

The extract of crofton weed (Eupatorium adenophorum) inhibits seed germination and weed growth; however, the physiological mechanisms underlying the effect of crofton weed extract on the modulation of seedling growth and root system development remain largely unclear. In this study, we investigated the effects of the leaf extract of crofton weed (LECW) on primary root (PR) growth in maize seedlings. Treatment with LECW markedly inhibited seed germination and seedling growth in a dose-dependent manner. Physiological analysis indicated that the LECW induced reactive oxygen species (ROS) accumulation in root tips, thereby leading to cell swelling and deformation both in the root cap and elongation zone of root tips, finally leading to cell death in root border cells (RBCs) and PR growth inhibition. The LECW also inhibited pectin methyl esterase (PME) activity, thereby decreasing the RBC number. Taken together, our results indicated that the LECW inhibited PR growth by inducing ROS accumulation and subsequent cell death in RBCs. The present study provides a better understanding of how the LECW modifies root system development and provides insight for evaluating the toxicity of crofton weed extracts in plants.

A novel method to purify adenovirus based on increasing salt concentrations in buffer.

With the rapid development of gene therapy, gene-based medicine with adenovirus as vectors has become a new method for disease treatment. However, there are still enormous challenges in the large-scale production of adenoviruses for clinical use. Recent reports show that ion-exchange chromatography (IEC) is an effective tool for the isolation and purification of adenovirus. However, during the separation and purification, host cell protein and DNA, as well as serum from the culture medium, can non-specifically occupy numerous binding sites of the chromatography packings, thereby reducing the binding between the adenovirus and packing media. We here report a novel method for highly efficient purification of adenoviruses by increasing the salt concentrations of the samples to be ultrafiltrated by tangential flow filtration, the diafiltration buffer, and the samples for IEC purification. This method could significantly remove a large amount of serum proteins and host cell proteins, increase the amount of sample loaded on the IEC column, and improve the binding of the adenovirus samples to the packing media. A purity of > 95% could be obtained after one chromatography operation, and the number of purification steps and the amount of used packing media were reduced. The method is simple, economical, and efficient, and has excellent applications.

Mechanisms for enhanced antitumor immune responses induced by irradiated hepatocellular carcinoma cells engineered to express hepatitis B virus X protein.

Tumor associated antigen (TAA) induces both humoral immunity and cellular immunity. The T cell-mediated immune response has an important role in the immune response induced by TAA. The hepatitis B virus X protein (HBx) sequence is mapped with Custer of differentiation (CD)8+ T cell (CTL) epitopes, while a large number of studies have indicated that HBx may enhance the autophagy. In our previous study, a novel hepatocellular carcinoma vaccine was designed that was an irradiated HBx modified hepatocellular carcinoma cell vaccine in autophagic form, which significantly induced antitumor immune responses in vivo. However, the mechanism by which this vaccine contributes to enhancing antitumor immune responses have yet to be fully elucidated. In the present study, we examined how autophagy was induced by this vaccine's influence on the generation of the 'danger signal' by hepatoma tumor cells and the subsequent activation of the immunoresponse. The data showed that the vaccine induced phenotypic maturation of DCs, which leads to efficient cross-presentation and a specific response. Both CD8+ and CD4+ T lymphocytes were involved in the antitumor immune response, as reflected by IFN-γ secretion. In addition, damage-associated molecular pattern molecules (DAMPs) were significantly elevated in the vaccine, and the elevation of DAMPs was autophagy-dependent. Furthermore, the antitumor activity was achieved by adoptive transfer of lymphocytes but not serum. The present findings indicated that this vaccine enhanced antitumor immune responses, which was in accordance with our previous study.