Discovery of multiple lead compounds as M2 inhibitors through the focused screening of a small primary amine library.

The discovery of new anti-influenza drugs is urgent, particularly considering the recent threat of swine flu. In this study, the influenza virus M2 protein was expressed in HEK293 cells and shown to have selective ion channel activity for monovalent ions. The anti-influenza virus drug amantadine hydrochloride significantly attenuated the inward current induced by hyperpolarization of HEK293 cell membranes. Although adamantine derivatives are the only M2 drugs for influenza virus A, their use is limited in the US due to drug resistance. Here we report the discovery of multiple M2 inhibitor lead compounds that were rapidly generated through focused screening of a small primary amine library. The screen was designed using a scaffold-hopping strategy based on amantadine. This study suggests that an antiviral compound directed against a conserved motif may be more useful than amantadine in inhibiting viral replication

2004 Roster

2004 Women\u27s Softball Roster, George Fox College

Seroprevalence of Neutralizing Antibodies to Human Adenovirus Type 4 and 7 in Healthy Populations From Southern China

Human adenoviruses type 4 (HAdV4) and 7 (HAdV7) are two major respiratory pathogens and sporadically cause outbreaks of acute respiratory diseases. The neutralizing antibody (nAb) response to these two adenoviruses in civilian populations, which is important for dissecting previous circulations and predicting potential outbreaks, remains largely unknown. In this study, we generated replication-competent HAdV4 and HAdV7 reporter viruses expressing secreted-alkaline-phosphatase (SEAP), and established neutralization assays to investigate the seroprevalence of pre-existing nAb in healthy volunteers from Hunan Province, southern China. The seropositivity rates are 58.4 and 63.8% for anti-HAdV4 nAb and anti-HAdV7 nAb, respectively. High nAb titers (> 1000) were frequently detected in HAdV4-seropositive individuals, whereas most HAdV7-seropositive volunteers had moderate nAb titers (201–1000). The seropositivity rates of anti-HAdV4 nAb and anti-HAdV7 nAb increase with age, with individuals younger than 20 exhibiting the lowest seropositivity rates. Both seropositivity rates and nAb titers are comparable between different sex groups. Notably, HAdV4-seropositive individuals tend to be HAdV7-seropositive and vice versa. Because HAdV4 antisera showed no neutralizing activity to HAdV7 whereas HAdV7 antisera cannot neutralize HAdV4, a subgroup of individuals might be susceptible to infection by HAdV4 and HAdV7 and thus generate nAb to both of them. These results revealed the continuous circulation of HAdV4 and HAdV7 and the lack of protective immunity in more than 35% of people, which emphasized the surveillance of these two HAdVs and the development of prophylactic vaccines

Differential Spectral Normalization (DSN) for PDE Discovery

Partial differential equations (PDEs) play a prominent role in many disciplines for describing the governing systems of interest. Traditionally, PDEs are derived based on first principles. In the era of big data, the needs of uncovering PDEs from massive data-set are emerging and become essential. One of the latest advance in PDE discovery models is PDE-Net, which has shown promising predictive power with its moment-constrained convolutional filters, but may suffer from noisy data and numerical instability intrinsic in numerical differentiation. We propose a novel and robust regularization method tailored for moment-constrained convolutional filters, namely, Differential Spectral Normalization (DSN), to allow accurate estimation of coefficient functions and stable prediction of dynamics in a long time horizon. We investigated the effectiveness of DSN against batch normalization, dropout, spectral normalization, weight decay, weight normalization, jacobian regularization and orthonormal regularization and supported with empirical evidence that DSN owns the highest effectiveness by learning the convolutional filters in a robust manner. Numerical experiments further reveal that with DSN there is a substantial potential to uncover the hidden PDEs in a scarce data setting and predict the dynamical behavior for a long time horizon, even in a noisy environment where all data samples are contaminated with noise

Generation of Replication-Competent Recombinant Influenza A Viruses Carrying a Reporter Gene Harbored in the Neuraminidase Segment▿

Replication-competent influenza viruses carrying reporter genes are of great use for basic research, screening of antiviral drugs, and neutralizing of antibodies. In this study, two recombinant influenza A viruses with a neuraminidase (NA) segment harboring enhanced green fluorescent protein (EGFP) in the background of A/PR/8/34 (PR8) were generated. The viral RNA (vRNA)-specific packaging signals for NA were largely retained for efficient packaging. An “autocleave” 2A peptide sequence, which was inserted at the N terminus or the COOH terminus of NA to link with EGFP, enabled NA and EGFP to be expressed monocistronically. Further analysis demonstrated that both viruses, named rPR8-EGFP+NA and rPR8-NA+EGPF, although with some characteristic differences in growth and EGFP expression, could replicate in noncomplementary cells and propagate to large quantities while maintaining genome stability after multiple passages in embryonated eggs. These replication-competent influenza viruses carrying reporter genes are a great addition to the tool set for developing antiviral therapeutics and vaccines and for in vivo studies of viral dissemination and pathogenicity

Regulation of SIV antigen-specific CD4+ T cellular immunity via autophagosome-mediated MHC II molecule-targeting antigen presentation in mice.

CD4+ T cell-mediated immunity has increasingly received attention due to its contribution in the control of HIV viral replication; therefore, it is of great significance to improve CD4+ T cell responses to enhance the efficacy of HIV vaccines. Recent studies have suggested that macroautophagy plays a crucial role in modulating adaptive immune responses toward CD4+ T cells or CD8+ T cells. In the present study, a new strategy based on a macroautophagy degradation mechanism is investigated to enhance CD4+ T cell responses against the HIV/SIV gag antigen. Our results showed that when fused to the autophagosome-associated LC3b protein, SIVgag protein can be functionally targeted to autophagosomes, processed by autophagy-mediated degradation in autolysosomes/lysosomes, presented to MHC II compartments and elicit effective potential CD4 T cell responses in vitro. Importantly, compared with the SIVgag protein alone, SIVgag-LC3b fusion antigen can induce a stronger antigen-specific CD4+ T cell response in mice, which is characterized by an enhanced magnitude and polyfunctionality. This study provides insight for the immunological modulation between viral and mammalian cells via autophagy, and it also presents an alternative strategy for the design of new antigens in the development of effective HIV vaccines

Influenza Virus Carrying a Codon-Reprogrammed Neuraminidase Gene as a Strategy for Live Attenuated Vaccine

Live attenuated influenza vaccines offer broader and longer-lasting protection in comparison to inactivated influenza vaccines. The neuraminidase (NA) surface glycoprotein of influenza A virus is essential for the release and spread of progeny viral particles from infected cells. In this study, we de novo synthesized the NA gene, in which 62% of codons were synonymously changed based on mammalian codon bias usage. The codon-reprogrammed NA (repNA) gene failed to be packaged into the viral genome, which was achievable with partial restoration of wild-type NA sequence nucleotides at the 3′ and 5′ termini. Among a series of rescued recombinant viruses, we selected 20/13repNA, which contained 20 and 13 nucleotides of wild-type NA at the 3′ and 5′ termini of repNA, respectively, and evaluated its potential as a live attenuated influenza vaccine. The 20/13repNA is highly attenuated in mice, and the calculated LD50 was about 10,000-fold higher than that of the wild-type (WT) virus. Intranasal inoculation of the 20/13repNA virus in mice induced viral-specific humoral, cell-mediated, and mucosal immune responses. Mice vaccinated with the 20/13repNA virus were protected from the lethal challenge of both homologous and heterologous viruses. This strategy may provide a new method for the development of live, attenuated influenza vaccines for a better and more rapid response to influenza threats

Tibetan medicine Jiuwei Qingpeng San could inhibit influenza A virus induced lung injury via regulating the expression of IFN-γ and its signaling pathway

Introduction: The Tibetan formula Jiuwei Qingpeng San (JWQPS) has been applied for severe respiratory infection with a centuries-old history and contemporarily applied for influenza induced pneumonia. Although it is empirically effective, its antiviral efficacy and the underlying mechanisms against influenza A (IAV) virus induced lung injury have not been elucidated yet. Methods: The in vitro anti-viral activity of JWQPS against H1N1 was reflected by the detection of cell viability of PR8 infected BEAS-2B cells. A replication competent PR8 carrying Gaussia luciferase (PR8-Luci) was further utilized to infect BEAS-2B cells to determine the inhibitory activity of virus replication by detection of the intensity of bioluminescence that correlates with viral load. Transcriptome was utilized to analyze the differences of the gene expression profiles in BEAS-2B cell line between the groups with or without JWQPS treatment after PR8 infection. BALB/c mice were intranasally inoculated with 60 or 150 p.f.u. of PR8 and intragastric administered with JWQPS (400 mg/kg/day, 200 mg/kg/day, 100 mg/kg/day). The mice infected with lethal dosages of 60 p.f.u. were monitored and weighed daily for 14 days and the survival rates were calculated. Concentrations of Nucleoprotein (NP) of IAV in BALF that stand for viral load were determined at 3 or 6 d.p.i. by enzyme linked immunosorbent assay (ELISA). Interferons and lymphotactin in the BALF collected at 3 d.p.i. were detected with the corresponding ELISA kits. The level of pro-inflammatory cytokines in BALF collected at 6 d.p.i. were detected using Th1/Th2 Cytokine 11-Plex Mouse ProcartaPlex Panel. The numbers of leukocyte in BALF were counted by an automated blood cell counter. The lung tissues of mice that were not subjected to BALF collection were harvested at 6 d.p.i. to check lung lesions by hematoxylin-eosin staining and lung coefficient calculation. Results: JWQPS inhibited IAV replication in vitro, down regulated NP in BALF of H1N1 infected BALB/c mice and protected the mice from IAV caused death. The elevated level of lymphotactin, IFN-γ and lymphocytes in BALF were observed 3 days post infection after JWQPS administration. The improved lung lesions, the alleviated leukocytes infiltration, and the decreased pro-inflammatory levels were observed 6 days post infection. Transcriptomic analysis of H1N1 infected lung epithelial cell line revealed JWQPS treatment could dramatically regulate the genes involved in defense response to virus and interferon associated signaling pathways. Discussion: Our study indicated that JWQPS could promote the chemotactic effect of lymphocytes towards site of infection to eliminate the pathogen at early phase of infection and alleviate the development of inflammation thereafter by reducing the occurrence of neutrophils and lymphocytes into the pulmonary alveoli by a rather complicated regulatory network in immune responses