Development of SARS-CoV-2 animal vaccines using a stable and efficient NDV expression system.

With the continuation of the coronavirus disease 2019 pandemic and the emergence of new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants, the control of the spread of the virus remains urgent. Various animals, including cats, ferrets, hamsters, nonhuman primates, minks, tree shrews, fruit bats, and rabbits, are susceptible to SARS-CoV-2 infection naturally or experimentally. Therefore, to avoid animals from becoming mixing vessels of the virus, vaccination of animals should be considered. In the present study, we report the establishment of an efficient and stable system using Newcastle disease virus (NDV) as a vector to express SARS-CoV-2 spike protein/subunit for the rapid generation of vaccines against SARS-CoV-2 in animals. Our data showed that the S and S1 protein was sufficiently expressed in rNDV-S and rNDV-S1-infected cells, respectively. The S protein was incorporated into and displayed on the surface of rNDV-S viral particles. Intramuscular immunization with rNDV-S was found to induce the highest level of binding and neutralizing antibodies, as well as strong S-specific T-cell response in mice. Intranasal immunization with rNDV-S1 provoked a robust T-cell response but barely any detectable antibodies. Overall, the NDV-vectored vaccine candidates were able to induce profound humoral and cellular immunity, which will provide a good system for developing vaccines targeting both T-cell and antibody responses.

Virus infection pattern imprinted and diversified the differentiation of T-cell memory in transcription and function.

Introduction: Memory T (Tm) cells are a subpopulation of immune cells with great heterogeneity. Part of this diversity came from T cells that were primed with different viruses. Understanding the differences among different viral-specific Tms will help develop new therapeutic strategies for viral infections. Methods: In this study, we compared the transcriptome of Tm cells that primed with CMV, EBV and SARS-CoV-2 with single-cell sequencing and studied the similarities and differences in terms of subpopulation composition, activation, metabolism and transcriptional regulation. Results: We found that CMV is marked by plentiful cytotoxic Temra cells, while EBV is more abundant in functional Tem cells. More importantly, we found that CD28 and CTLA4 can be used as continuous indicators to interrogate the antiviral ability of T cells. Furthermore, we proposed that REL is a main regulatory factor for CMV-specific T cells producing cytokines and plays an antiviral role. Discussion: Our data gives deep insight into molecular characteristics of Tm subsets from different viral infection, which is important to understand T cell immunization. Furthermore, our results provide basic background knowledges for T cell based vaccine development in future.

The establishment of a cytomegalovirus -specific CD8+ T-cell threshold by kinetic modeling for the prediction of post-hemopoietic stem cell transplant reactivation.

The dynamic interaction between the CMV virus and host immune response remains obscure, thus hindering the diagnosis and therapeutic management of patients with HSCT. The current diagnosis of CMV viremia depends on viral load estimation. Medical intervention based on viral load, can be unnecessary or poorly timed for many patients. Here we examined the clinical features and blood samples of patients with HSCT and assessed the CMV reactivation kinetics and corresponding CMV antigen-specific T-cell response in individual patients based on a peptide pool stimulation T-cell assay, which showed that CMV-specific CD8+ T cells were more suitable to be a diagnosis indicator for suppressing CMV reactivation. Using ROC analysis, we defined and verified a CMV-specific CD8+ T-cell counts threshold (925 cells/106 PBMCs) as an indicator of CMV reactivation post-HSCT, and suggested that use of this threshold would provide more accurate guidance for prompt medication and better management of CMV infection post-HSCT.

Pellino2 accelerate inflammation and pyroptosis via the ubiquitination and activation of NLRP3 inflammation in model of pediatric pneumonia.

BACKGROUND: Mycoplasma pneumoniae pneumonia (MPP) is a common and frequently-occurring disease in pediatrics. This study aims to via unveiling the novel effects and mechanisms of Pellino2 in model of pediatric pneumonia. MATERIALS AND METHODS: Male infancy C57BL/6 mice were injected with 2 mg/kg of LPS (Sigma-Aldrich Merck KGaA). THP-1 cells were induced with LPS and ATP. RESULTS: The expression of Pellino2 mRNA and protein in patients with pediatric pneumonia or mice with pediatric pneumonia were reduced. Pellino2 accelerated lung injury and expanded inflammation and pyroptosis in lung tissue of pediatric pneumonia in vivo and vitro model. Furthermore, the inhibition of Pellino2 reduced lung injury and weakened inflammation and pyroptosis in lung tissue of pediatric pneumonia in vivo and vitro model. Pellino2 protein catenated NLRP3 protein, and Pellino2 promoted ubiquitination and activation of NLRP3 inflammation in model of pediatric pneumonia. Pellino2 accelerate inflammation and pyroptosis in model of pediatric pneumonia by NLRP3. CONCLUSIONS: These results suggest that Pellino2 accelerate inflammation and pyroptosis via the induction of ubiquitination and activation of NLRP3 inflammation in model of pediatric pneumonia, Pellino2 may serve as a potential approach for the treatment of pediatric pneumonia and other inflammatory diseases.

Evodiamine Enhanced the Anti-Inflammation Effect of Clindamycin in the BEAS-2B Cells Infected with H5N1 and Pneumoniae D39 Through CREB-C/EBPß Signaling Pathway.

Pneumonia is a pulmonary disease among children. Evodiamine, a traditional Chinese medicine, is known for anti-inflammatory effect. This study aimed to investigate the impact of evodiamine on severe pneumonia-like cells and the underlying mechanism involved. H5N1 and pneumoniae D39 was used to induce severe pneumonia-like conditions in BEAS-2B cells. The cell viability in BEAS-2B cells after treatments with 0, 20, 40, 60, 80, and 100 µM evodiamine was examined using MTT assays. The protein concentrations of inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß, and Toll-like receptors (TLRs) were measured by enzyme-linked immunosorbent assay methods and the protein and mRNA changes in C/EBPß/CREB were measured using Real Time-quantitative polymerase chain reaction and Western blot methods. Our results revealed that Evodiamine significantly decreased TNF-α, IL-6, and IL-1ß in BEAS-2B cells. Moreover, evodiamine markedly reduced TLR2,3,4 protein expression and the phosphorylated protein of C/EBPß and CREB. Besides, evodiamine combined with clindamycin exerted more significant effects than clindamycin alone. Taken together, our results demonstrated that evodiamine enhanced the anti-inflammation effect of clindamycin in the BEAS-2B cells infected with H5N1 and pneumoniae D39 through CREB-C/EBPß signaling pathway.

Pellino1 promoted inflammation in lung injury model of sepsis by TRAF6/ NF-κB signal pathway.

BACKGROUND: This study was designed to investigate the role of Pellino1 in lung injury model of sepsis and its anti-inflammation mechanism. METHOD: C57BL/6 male mice (6-7 weeks old) and Pellino1-/- male mice were subjected to laparotomy followed by extracorporeal cecum mobilization and ligation. THP-1 cells were treated with 500 ng/ml of LPS for 4 h. Both mRNA and protein expression of Pellino1 was increased at time dependence in lung tissue of lung injury model of sepsis mice. Knockout of Pellino1 attenuated lung injury and inhibited inflammation of sepsis mice. While Pellino1 protein enhanced lung injury and increased inflammation of sepsis mice. Pellino1 promoted inflammation in in vitro model of lung injury by TRAF6/ NF-κB signal pathway. RESULT: TRAF6 inhibitor attenuated the effects of Pellino1 on inflammation and lung injury in mice of sepsis. Similarly, NF-κB inhibitor also suppressed the effects of Pellino1 on inflammation and lung injury in mice of sepsis. The activation of TRAF6 or induction of NF-κB attenuated the effects of Pellino1 on inflammation in in vitro model of sepsis. The inhibition of TRAF6 or suppression of NF-κB reduced the effects of Pellino1 on inflammation in in vitro model of sepsis. CONCLUSIONS: These results suggested that Pellino1 promoted inflammation in lung injury model of sepsis by TRAF6/ NF-κB signal pathway.

Complex Involvement of the Extracellular Matrix, Immune Effect, and Lipid Metabolism in the Development of Idiopathic Pulmonary Fibrosis.

Background and objective: Idiopathic pulmonary fibrosis (IPF) is an aggressive fibrotic pulmonary disease with spatially and temporally heterogeneous alveolar lesions. There are no early diagnostic biomarkers, limiting our understanding of IPF pathogenesis. Methods: Lung tissue from surgical lung biopsy of patients with early-stage IPF (n = 7), transplant-stage IPF (n = 2), and healthy controls (n = 6) were subjected to mRNA sequencing and verified by real-time quantitative PCR (RT-qPCR), immunohistochemistry, Western blot, and single-cell RNA sequencing (scRNA-Seq). Results: Three hundred eighty differentially expressed transcripts (DETs) were identified in IPF that were principally involved in extracellular matrix (ECM) remodeling, lipid metabolism, and immune effect. Of these DETs, 21 (DMD, MMP7, POSTN, ECM2, MMP13, FASN, FADS1, SDR16C5, ACAT2, ACSL1, CYP1A1, UGT1A6, CXCL13, CXCL5, CXCL14, IL5RA, TNFRSF19, CSF3R, S100A9, S100A8, and S100A12) were selected and verified by RT-qPCR. Differences in DMD, FASN, and MMP7 were also confirmed at a protein level. Analysis of scRNA-Seq was used to trace their cellular origin to determine which lung cells regulated them. The principal cell sources of DMD were ciliated cells, alveolar type I/II epithelial cells (AT cells), club cells, and alveolar macrophages (AMs); MMP7 derives from AT cells, club cells, and AMs, while FASN originates from AT cells, ciliated cells, and AMs. Conclusion: Our data revealed a comprehensive transcriptional mRNA profile of IPF and demonstrated that ECM remodeling, lipid metabolism, and immune effect were collaboratively involved in the early development of IPF.

The inhibition of enterovirus 71 induced apoptosis by Durvillaea antarctica through P53 and STAT1 signaling pathway.

The infection of enterovirus 71 (EV71) resulted in hand, foot, and mouth disease and may lead to severe nervous system damage and even fatalities. There are no effective drugs to treat the EV71 virus and it is crucial to find novel drugs against it. Polysaccharide isolated from Durvillaea antarctica green algae has an antiviral effect. In this study, D. antarctica polysaccharide (DAPP) inhibited the infection of EV71 was demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), reverse transcription polymerase chain reaction, flow cytometry, and western blot. MTT assay showed that DAPP had no toxicity on Vero cells at the concentration 250 µg/ml. Furthermore, DAPP significantly reduced the RNA level of EV71 in a dose-dependent manner. Moreover, DAPP inhibited the Vero cells apoptosis induced by EV71 via the P53 signaling pathway. Meanwhile, the expression of signal transducer and activator of transcription 1 and mammalian target of rapamycin were increased and the proinflammatory cytokines were significantly inhibited by DAPP. Taken together, these results suggested that DAPP could be a potential pharmaceutical against the infection of EV71 virus.

The Inhibition of H1N1 Influenza Virus-Induced Apoptosis by Surface Decoration of Selenium Nanoparticles with ß-Thujaplicin through Reactive Oxygen Species-Mediated AKT and p53 Signaling Pathways.

ß-Thujaplicin possess a variety of biological activities. The use of modified biological nanoparticles (NPs) to develop novel anti-influenza drugs has increased in recent years. Selenium nanoparticles (SeNPs) with antiviral activity have attracted increasing attention for biomedical intervention. Functionalized SeNPs by ß-thujaplicin (Se@TP) surface modified with superior antiviral activity were synthesized in this study. Compared to a virus group (43%), when treated with Se@TP (88%), the cell survival rate of MDCK cells was 45% higher. Se@TP could inhibit H1N1 from infecting Madin-Darby canine kidney (MDCK) cells and block chromatin condensation and DNA fragmentation. Se@TP obviously prevented MDCK cells from generating reactive oxygen species. Furthermore, Se@TP prevents lung injury in H1N1-infected mice through eosin staining and hematoxylin in vivo. Mechanistic investigation revealed that Se@TP inhibited H1N1 influenza virus from infecting MDCK cells through induction of apoptosis via suppressing AKT and p53 signaling pathways through immunohistochemical assay. Our results suggest that ß-thujaplicin-modified SeNPs as carriers are an efficient way to achieve an antiviral pharmaceutical candidate for H1N1 influenza.

Inhibition of Enterovirus 71 by Selenium Nanoparticles Loaded with siRNA through Bax Signaling Pathways.

Enterovirus 71 (EV71) is the principal pathogen leading to severe cases of hand, foot, and mouth disease (HFMD). Specific drugs for EV71 are not discovered currently. Small interfering RNA (siRNA) provides a promising antiviral treatment pathway, but it is difficult to cross cell membranes and is easy to degrade. Nanoparticles are promising for their carrying capacity currently. In this study, the siRNA targeting EV71 VP1 gene was loaded with selenium nanoparticles (SeNPs) and surface decorated with polyethylenimine (PEI) (Se@PEI@siRNA). Se@PEI@siRNA showed a remarkable interference efficiency in the nerve cell line SK-N-SH and prevented the cells to be infected. The mechanism study revealed that Se@PEI@siRNA could lighten the extent of SK-N-SH cells for staying in the sub-G1 phase. Activation of Bax apoptosis signaling was restrained either. Taken together, this study demonstrated that Se@PEI@siRNA is a promising drug against EV71 virus.

Silencing KLK12 expression via RGDfC-decorated selenium nanoparticles for the treatment of colorectal cancer in vitro and in vivo.

Short interfering RNA (siRNA) has been investigated as a promising modality of cancer treatment due to its capability to target specific target genes for downregulation. However, the successful application of this strategy depends on producing a safe and effective carrier system for delivering siRNA to the tumor. Thus, investigation of siRNA delivery carriers is a fundamental step in the field of siRNA-based therapeutics. In the current research, the surface of selenium nanoparticles (SeNPs) were modified with the tumor-targeted molecular RGDfC peptide with positive charge to synthetize the biocompatible siRNA carrier RGDfC-SeNPs. Subsequently, KLK12-siRNA was loaded onto the surface of RGDfC-SeNPs to create functionalized nanoparticles (RGDfC-Se@siRNA) that we tested for in vitro and in vivo antitumor efficacy. We measured significantly greater particle uptake in HT-29 colorectal cancer cells relative to HUVECs, providing evidence for the targeted delivery of RGDfC-Se@siRNA. We found that RGDfC-Se@siRNA could enter HT-29 cells primarily via clathrin-mediated endocytosis. Further, these particles experienced faster siRNA release in an acidic microenvironment compared to pH 7.4. The results from quantitative PCR and Western blot assays suggested that the target gene of KLK12 in HT-29 cells were obviously silenced by RGDfC-Se@siRNA. The further biological studies showed that treatment with RGDfC-Se@siRNA had ability to suppress the proliferation and migration/invasion of HT-29 cells, and triggered HT-29 cells apoptosis. RGDfC-Se@siRNA could induce the mitochondrial membrane potential (MMP) disruption and enhance the reactive oxygen species (ROS) generation in HT-29 cells, indicating that RGDfC-Se@siRNA induced the HT-29 cells apoptosis possibly by a ROS-mediated mitochondrial dysfunction pathway. Importantly, the in vivo antitumor study also verified that RGDfC-Se@siRNA could significantly suppress the growth of tumor in vivo. In addition, we did not observe any signs of systemic or tissue-specific toxicity after administration of RGDfC-Se@siRNA in mice. As a whole, these findings suggest that RGDfC-Se@siRNA has promising potential as a therapy for colorectal cancer.

Characterization of lymphocyte subsets in peripheral blood cells of children with EV71 infection.

BACKGROUND: Enterovirus 71 (EV71) is one of the major causative pathogens of hand, foot, and mouth disease (HFMD). Immune cells play a critical role in determining the outcomes of virus infection. We aimed to characterize the lymphocyte subsets and transcriptional levels of T lymphocytes-associated transcription factors in peripheral blood cells of children with EV71 infection. METHODS: Peripheral blood samples from 32 children with EV71 infection and 32 control subjects were included in this study. The frequencies of T-, B-lymphocytes, and their subsets were determined by flow cytometry. The expression of transcription factors, including T-bet, Gata3, ROR γ t, Foxp3, TCF-1, and BCL-6 in the whole blood cells were evaluated by real-time reverse-transcription quantitative polymerase chain reaction (RT-qPCR). RESULTS: The frequencies of T cells, helper T cells (Th), cytotoxic T cells (Tc), IFN-γ+ Th1, IFN-γ+ Tc1, and regulatory T (Treg) cells were significantly decreased (P < 0.01) in children with EV71 infection. As for IL-4+ Th2, IL-4+ Tc2, IL-17+ Th17, IL-17+ Tc17, follicular helper T cells (Tfh), CD3+CD8+IL-21+ T cells, CD19+ B cells, and CD19+IL-10+ B10 cells, their frequencies were significantly increased in the EV71 group (P < 0.01). The EV71 group had lower mRNA expressions of T-bet, Gata3, and Foxp3 than the control group (P < 0.05), whereas the expressions of ROR γ t, TCF-1, and BCL-6 showed no significant difference between two groups. CONCLUSIONS: EV71 infection in children caused a decreased frequency of total Th, Tc and Treg cells, and increased percentages of B cell, Th2 and Th17 cells in blood.

Heat shock protein 70 as a supplementary receptor facilitates enterovirus 71 infections in vitro.

As one of the major causative agents of hand, foot and mouth disease (HFMD), enterovirus 71 (EV71) is a small, non-enveloped positive stranded RNA virus. Children suffering EV71 infection may cause severe symptoms including neurological complications, pulmonary edema and aseptic meningitis. EV71 is a neurotropic virus and it can cause the damage of nervous cells, cytokine storm and toxic substance. Identifying the factors that mediate viral binding or entry to host cells is important to uncover the mechanisms which viruses utilize to cause diseases in human body. Heat shock protein 70 (HSP70) is induced during virus infection and facilitates proper protein folding during viral propagation. The role that HSP70 plays during EV71 infection is still unclear. In this study, siRNA interference technique and transgenic technique were used to investigate the interaction between HSP70 and EV71 virus. The result demonstrated that the cell surface HSP70 is not essential for EV71 infection but helps the initial binding of virus to host cells and that multiple receptors are involved during EV71 infection. In addition, HSP70 was upregulated in human neuroblastoma cells (SK-N-SH) infected with EV71.

Multifunctional selenium nanoparticles with Galangin-induced HepG2 cell apoptosis through p38 and AKT signalling pathway.

The morbidity and mortality of hepatocellular carcinoma, the most common cancer, are increasing continuously worldwide. Galangin (Ga) has been demonstrated to possess anti-cancer effect, but the efficacy of Ga was limited by its low permeability and poor solubility. To develop aqueous formulation and improve the anti-cancer activity of Ga, surface decoration of functionalized selenium nanoparticles with Ga (Se@Ga) was synthesized in the present study. The aim of this study was to evaluate the anti-cancer effect of Se@Ga and the mechanism on HepG2 cells. Se@Ga-induced HepG2 cell apoptosis was confirmed by depletion of mitochondrial membrane potential, translocation of phosphatidylserine and caspase-3 activation. Furthermore, Se@Ga enhanced the anti-cancer activity of HepG2 cells through ROS-mediated AKT and p38 signalling pathways. In summary, these results suggest that Se@Ga might be potential candidate chemotherapy for cancer.

Restriction of H1N1 influenza virus infection by selenium nanoparticles loaded with ribavirin via resisting caspase-3 apoptotic pathway.

INTRODUCTION: Ribavirin (RBV) is a broad-spectrum antiviral drug. Selenium nanoparticles (SeNPs) attract much attention in the biomedical field and are used as carriers of drugs in current research studies. In this study, SeNPs were decorated by RBV, and the novel nanoparticle system was well characterized. Madin-Darby Canine Kidney cells were infected with H1N1 influenza virus before treatment with RBV, SeNPs, and SeNPs loaded with RBV (Se@RBV). METHODS AND RESULTS: MTT assay showed that Se@RBV nanoparticles protect cells during H1N1 infection in vitro. Se@RBV depressed virus titer in the culture supernatant. Intracellular localization detection revealed that Se@RBV accumulated in lysosome and escaped to cytoplasm as time elapsed. Furthermore, activation of caspase-3 was resisted by Se@RBV. Expressions of proteins related to caspase-3, including cleaved poly-ADP-ribose polymerase, caspase-8, and Bax, were downregulated evidently after treatment with Se@RBV compared with the untreated infection group. In addition, phosphorylations of phosphorylated 38 (p38), JNK, and phosphorylated 53 (p53) were inhibited as well. In vivo experiments indicated that Se@RBV was found to prevent lung injury in H1N1-infected mice through hematoxylin and eosin staining. Tunel test of lung tissues present that DNA damage reached a high level but reduced substantially when treated with Se@RBV. Immunohistochemical test revealed an identical result with the in vitro experiment that activations of caspase-3 and proteins on the apoptosis pathway were restrained by Se@RBV treatment. CONCLUSION: Taken together, this study elaborates that Se@RBV is a novel promising agent against H1N1 influenza virus infection.

Inhibition of H1N1 influenza virus-induced apoptosis by functionalized selenium nanoparticles with amantadine through ROS-mediated AKT signaling pathways.

INTRODUCTION: As a therapeutic antiviral agent, the clinical application of amantadine (AM) is limited by the emergence of drug-resistant viruses. To overcome the drug-resistant viruses and meet the growing demand of clinical diagnosis, the use of biological nanoparticles (NPs) has increased in order to develop novel anti-influenza drugs. The antiviral activity of selenium NPs with low toxicity and excellent activities has attracted increasing attention for biomedical intervention in recent years. METHODS AND RESULTS: In the present study, surface decoration of selenium NPs by AM (Se@AM) was designed to reverse drug resistance caused by influenza virus infection. Se@ AM with less toxicity remarkably inhibited the ability of H1N1 influenza to infect host cells through suppression of the neuraminidase activity. Moreover, Se@AM could prevent H1N1 from infecting Madin Darby Canine Kidney cell line and causing cell apoptosis supported by DNA fragmentation and chromatin condensation. Furthermore, Se@AM obviously inhibited the generation of reactive oxygen species and activation of phosphorylation of AKT. CONCLUSION: These results demonstrate that Se@AM is a potentially efficient antiviral pharmaceutical agent for H1N1 influenza virus.

siRNA-loaded selenium nanoparticle modified with hyaluronic acid for enhanced hepatocellular carcinoma therapy.

BACKGROUND: Small interfering RNA (siRNA) as a new therapeutic modality holds promise for cancer treatment. However, the traditional viral carriers are prone to immunogenicity and risk of insertional mutagenesis. METHODS: In order to provide a tumor-targeted delivery carrier of siRNA in cancer therapy, the hyaluronic acid (HA)-selenium (Se)-polyethylenimine (PEI) nanoparticle (NP) was fabricated by decorating SeNP with HA as a tumor-targeting moiety and by linking the polycationic polymers polyethylenimine PEI onto the surface of SeNP. The siRNA was loaded to the surface of SeNP HA-Se-PEI via the electrostatic interaction between siRNA and PEI to prepare the functionalized SeNP HA-Se-PEI@siRNA. RESULTS: The HA-Se-PEI@siRNA was internalized into the HepG2 cell mainly in a clathrin-mediated endocytosis manner. Owing to the active tumor-targeted effect mediated by HA, HA-Se-PEI@siRNA achieved the obvious higher transfection efficiency, greater gene silencing ability, and stronger cytotoxicity in the HepG2 cell compared with the passive tumor-targeted NP Se-PEI@siRNA. The knockdown of hairy and enhancer of split 5 by HA-Se-PEI@siRNA induced the HepG2 cell cycle arrest at the G0/G1 phase and apoptosis. Furthermore, the treatment with HA-Se-PEI@siRNA resulted in greater antitumor efficacy compared with the Se-PEI@siRNA in vitro and in vivo. In addition, the HA-Se-PEI@siRNA was almost no toxic to the key organs of mice. CONCLUSION: These findings provided an alternative therapeutic route for targeted cancer treatments.

Novel functionalized nanoparticles for tumor-targeting co-delivery of doxorubicin and siRNA to enhance cancer therapy.

Human homeobox protein (Nanog) is highly expressed in most cancer cells and has gradually emerged as an excellent target in cancer therapy, owing to its regulation of cancer cell proliferation, metastasis and apoptosis. In this study, we prepared tumor-targeting functionalized selenium nanoparticles (RGDfC-SeNPs) to load chemotherapeutic doxorubicin (DOX) and Nanog siRNA. Herein, RGDfC peptide was used as a tumor-targeting moiety which could specifically bind to αvß3 integrins overexpressed on various cancer cells. The sizes of RGDfC-SeNPs@DOX nanoparticles (~12 nm) were confirmed by both dynamic light scattering and transmission electron microscopy. The chemical structure of RGDfC-SeNPs@DOX was characterized via Fourier-transform infrared spectroscopy. The RGDfC-SeNPs@DOX was compacted with siRNA (anti-Nanog) by electrostatic interaction to fabricate the RGDfC-SeNPs@DOX/siRNA complex. The RGDfC-SeNPs@DOX/siRNA complex nanoparticles could efficiently enter into HepG2 cells via clathrin-associated endocytosis, and showed high gene transfection efficiency that resulted in enhanced gene silencing. The in vivo biodistribution experiment indicated that RGDfC-SeNPs@DOX/siRNA nanoparticles were capable of specifically accumulating in the tumor site. Furthermore, treatment with RGDfC-SeNPs@DOX/siRNA resulted in a more significant anticancer activity than the free DOX, RGDfC-SeNPs@DOX or RGDfC-SeNPs/siRNA in vitro and in vivo. In summary, this study shows a novel type of DOX and siRNA co-delivery system, thereby providing an alternative route for cancer treatment.

Targeted delivery of HES5-siRNA with novel polypeptide-modified nanoparticles for hepatocellular carcinoma therapy.

For actively targeted delivery of small interfering RNA (siRNA) to solid tumors, we fabricated functionalized selenium nanoparticles (SeNPs) decorated with the polypeptide RGDfC. Herein, RGDfC was used as tumor-targeted moiety and installed onto the surface of SeNPs to enhance the cellular uptake. RGDfC-SeNPs@siRNA were internalized into the HepG2 cell mainly through clathrin-mediated endocytosis. The active efficacy of the RGDfC-SeNPs@siRNA was confirmed via gene silencing assay, MTT assay and flow cytometry analysis. Owing to the tumor-targeting effect of RGDfC, RGDfC-SeNPs@siRNA achieved an obvious improvement in gene silencing ability, which led to significant growth inhibition of HepG2 cells. Furthermore, treatment with RGDfC-SeNPs@siRNA resulted in greater antitumor efficacy than lipofectamine 2000@siRNA in vitro and in vivo. In addition, the RGDfC-SeNPs@siRNA was almost non-toxic to the key organs of mice. In sum, these findings provide an alternative therapeutic route for targeted cancer treatments.

Inhibitory activity of selenium nanoparticles functionalized with oseltamivir on H1N1 influenza virus.

As an effective antiviral agent, the clinical application of oseltamivir (OTV) is limited by the appearance of drug-resistant viruses. Due to their low toxicity and excellent activity, the antiviral capabilities of selenium nanoparticles (SeNPs) has attracted increasing attention in recent years. To overcome the limitation of drug resistance, the use of modified NPs with biologics to explore novel anti-influenza drugs is developing rapidly. In this study, OTV surface-modified SeNPs with superior antiviral properties and restriction on drug resistance were synthesized. OTV decoration of SeNPs (Se@OTV) obviously inhibited H1N1 infection and had less toxicity. Se@OTV interfered with the H1N1 influenza virus to host cells through inhibiting the activity of hemagglutinin and neuraminidase. The mechanism was that Se@OTV was able to prevent H1N1 from infecting MDCK cells and block chromatin condensation and DNA fragmentation. Furthermore, Se@OTV inhibited the generation of reactive oxygen species and activation of p53 phosphorylation and Akt. These results demonstrate that Se@OTV is a promising efficient antiviral pharmaceutical for H1N1.