Immunogenicity and protective efficacy of a Vero cell culture-derived whole-virus H7N9 vaccine in mice and guinea pigs.

Background: A novel avian H7N9 virus with a high case fatality rate in humans emerged in China in 2013. We evaluated the immunogenicity and protective efficacy of a candidate Vero cell culture-derived whole-virus H7N9 vaccine in small animal models.

Methods: Antibody responses induced in immunized DBA/2J mice and guinea pigs were evaluated by hemagglutination inhibition (HI), microneutralization (MN), and neuraminidase inhibition (NAi) assays.

MVA vectors expressing conserved influenza proteins protect mice against lethal challenge with H5N1, H9N2 and H7N1 viruses.

Background: The availability of a universal influenza vaccine able to induce broad cross-reactive immune responses against diverse influenza viruses would provide an alternative to currently available strain-specific vaccines. We evaluated the ability of vectors based on modified vaccinia virus Ankara (MVA) expressing conserved influenza proteins to protect mice against lethal challenge with multiple influenza subtypes.

Methods: Mice were immunized with MVA vectors expressing H5N1-derived nucleoprotein (NP), the stem region of hemagglutinin (HA), matrix proteins 1 and 2 (M1 and M2), the viral polymerase basic protein 1 (PB1), or the HA stem fused to a quadrivalent matrix protein 2 extracellular domain (M2e).

Evaluation of OspA vaccination-induced serological correlates of protection against Lyme borreliosis in a mouse model.

Background: For clinical development of a novel multivalent OspA vaccine against Lyme borreliosis, serological assays are required which can be used to establish immune correlates of protection against infection with Borrelia.

Methods: Four assays (an OspA IgG ELISA, a competitive inhibition (CI) ELISA, a Borrelia surface-binding (SB) assay and a Borrelia killing assay) were used to evaluate the correlation between immune responses induced by rOspA 1/2 (a chimeric immunogen containing protective epitopes from OspA serotypes 1 and 2), and protective immunity against infection by B. burgdorferi s.

Preclinical evaluation of Vaxfectin-adjuvanted Vero cell-derived seasonal split and pandemic whole virus influenza vaccines.

Increasing the potency and supply of seasonal and pandemic influenza vaccines remains an important unmet medical need which may be effectively accomplished with adjuvanted egg- or cell culture-derived vaccines. Vaxfectin, a cationic lipid-based adjuvant with a favorable safety profile in phase 1 plasmid DNA vaccines trials, was tested in combination with seasonal split, trivalent and pandemic whole virus, monovalent influenza vaccines produced in Vero cell cultures. Comparison of hemagglutination inhibition (HI) antibody titers in Vaxfectin-adjuvanted to nonadjuvanted vaccinated mice and guinea pigs revealed 3- to 20-fold increases in antibody titers against each of the trivalent influenza virus vaccine strains and 2- to 8-fold increases in antibody titers against the monovalent H5N1 influenza virus vaccine strain.

A cell culture-derived whole-virus H5N1 vaccine induces long-lasting cross-clade protective immunity in mice which is augmented by a homologous or heterologous booster vaccination.

Background: Preparation for an H5N1 influenza pandemic in humans could include priming the population in the pre-pandemic period with a vaccine produced from an existing H5N1 vaccine strain, with the possibility of boosting with a pandemic virus vaccine when it becomes available. We investigated the longevity of the immune response after one or two priming immunizations with a whole-virus H5N1 vaccine and the extent to which this can be boosted by later immunization with either a homologous or heterologous vaccine.

Methods: Mice received one or two priming immunizations with a Vero cell culture-derived, whole-virus clade 1 H5N1 vaccine formulated to contain either 750 ng or 30 ng hemagglutinin.

A cell culture-derived whole-virus H9N2 vaccine induces high titer antibodies against hemagglutinin and neuraminidase and protects mice from severe lung pathology and weight loss after challenge with a highly virulent H9N2 isolate.

Background: Influenza viruses of subtype A/H9N2 are enzootic in poultry across Asia and the Middle East and are considered to have pandemic potential. The development of new vaccine manufacturing technologies is a cornerstone of influenza pandemic preparedness.

Methods: A non-adjuvanted whole-virus H9N2 vaccine was developed using Vero cell culture manufacturing technology.

Neutralization of macrophage migration inhibitory factor (MIF) by fully human antibodies correlates with their specificity for the β-sheet structure of MIF.

The macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that recently emerged as an attractive therapeutic target for a variety of diseases. A diverse panel of fully human anti-MIF antibodies was generated by selection from a phage display library and extensively analyzed in vitro. Epitope mapping studies identified antibodies specific for linear as well as structural epitopes.

H5N1 whole-virus vaccine induces neutralizing antibodies in humans which are protective in a mouse passive transfer model.

Background: Vero cell culture-derived whole-virus H5N1 vaccines have been extensively tested in clinical trials and consistently demonstrated to be safe and immunogenic; however, clinical efficacy is difficult to evaluate in the absence of wide-spread human disease. A lethal mouse model has been utilized which allows investigation of the protective efficacy of active vaccination or passive transfer of vaccine induced sera following lethal H5N1 challenge.

Methods: We used passive transfer of immune sera to investigate antibody-mediated protection elicited by a Vero cell-derived, non-adjuvanted inactivated whole-virus H5N1 vaccine.

Evaluation of an inactivated Ross River virus vaccine in active and passive mouse immunization models and establishment of a correlate of protection.

Ross River Virus has caused reported outbreaks of epidemic polyarthritis, a chronic debilitating disease associated with significant long-term morbidity in Australia and the Pacific region since the 1920s. To address this public health concern, a formalin- and UV-inactivated whole virus vaccine grown in animal protein-free cell culture was developed and tested in preclinical studies to evaluate immunogenicity and efficacy in animal models. After active immunizations, the vaccine dose-dependently induced antibodies and protected adult mice from viremia and interferon α/β receptor knock-out (IFN-α/βR(-/-)) mice from death and disease.

Vectors based on modified vaccinia Ankara expressing influenza H5N1 hemagglutinin induce substantial cross-clade protective immunity.

Background: New highly pathogenic H5N1 influenza viruses are continuing to evolve with a potential threat for an influenza pandemic. So far, the H5N1 influenza viruses have not widely circulated in humans and therefore constitute a high risk for the non immune population. The aim of this study was to evaluate the cross-protective potential of the hemagglutinins of five H5N1 strains of divergent clades using a live attenuated modified vaccinia Ankara (MVA) vector vaccine.

A new approach to a Lyme disease vaccine.

A single recombinant outer surface protein A (OspA) antigen designed to contain protective elements from 2 different OspA serotypes (1 and 2) is able to induce antibody responses that protect mice against infection with either Borrelia burgdorferi sensu stricto (OspA serotype-1) or Borrelia afzelii (OspA serotype-2). Protection against infection with B burgdorferi ss strain ZS7 was demonstrated in a needle-challenge model. Protection against B.

A pandemic influenza H1N1 live vaccine based on modified vaccinia Ankara is highly immunogenic and protects mice in active and passive immunizations.

Background: The development of novel influenza vaccines inducing a broad immune response is an important objective. The aim of this study was to evaluate live vaccines which induce both strong humoral and cell-mediated immune responses against the novel human pandemic H1N1 influenza virus, and to show protection in a lethal animal challenge model.

Methodology/principal Findings: For this purpose, the hemagglutinin (HA) and neuraminidase (NA) genes of the influenza A/California/07/2009 (H1N1) strain (CA/07) were inserted into the replication-deficient modified vaccinia Ankara (MVA) virus--a safe poxviral live vector--resulting in MVA-H1-Ca and MVA-N1-Ca vectors.

A whole virus pandemic influenza H1N1 vaccine is highly immunogenic and protective in active immunization and passive protection mouse models.

The recent emergence and rapid spread of a novel swine-derived H1N1 influenza virus has resulted in the first influenza pandemic of this century. Monovalent vaccines have undergone preclinical and clinical development prior to initiation of mass immunization campaigns. We have carried out a series of immunogenicity and protection studies following active immunization of mice, which indicate that a whole virus, nonadjuvanted vaccine is immunogenic at low doses and protects against live virus challenge.

Seasonal influenza vaccine elicits heterosubtypic immunity against H5N1 that can be further boosted by H5N1 vaccination.

Recent findings indicate that seasonal influenza vaccination or infection of healthy humans may contribute to heterosubtypic immunity against new influenza A subtypes, such as H5N1. Here, we investigated whether seasonal influenza vaccination in a mouse model could induce any immunity against the H5N1 subtype. It could be demonstrated that, largely due to the H1N1 component strain A/NewCaledonia/20/99, parenteral immunization of mice with a trivalent seasonal influenza vaccine elicited heterosubtype H5-reactive antibodies able to confer partial protection against H5N1 influenza virus infection.

Comparison of single, homologous prime-boost and heterologous prime-boost immunization strategies against H5N1 influenza virus in a mouse challenge model.

Preparation for an H5N1 influenza pandemic in humans may involve priming the population with a vaccine produced from an existing, available H5N1 strain. We have used a mouse challenge model to compare the immunogenicity and efficacy of inactivated, Vero cell-derived, whole virus H5N1 vaccines in single immunization and homologous or heterologous prime-boost regimes. A single immunization was sufficient to protect against a lethal challenge with strains from matched and unmatched H5N1 clades.

Nonreplicating vaccinia virus vectors expressing the H5 influenza virus hemagglutinin produced in modified Vero cells induce robust protection.

The timely development of safe and effective vaccines against avian influenza virus of the H5N1 subtype will be of the utmost importance in the event of a pandemic. Our aim was first to develop a safe live vaccine which induces both humoral and cell-mediated immune responses against human H5N1 influenza viruses and second, since the supply of embryonated eggs for traditional influenza vaccine production may be endangered in a pandemic, an egg-independent production procedure based on a permanent cell line. In the present article, the generation of a complementing Vero cell line suitable for the production of safe poxviral vaccines is described.

Cell culture (Vero) derived whole virus (H5N1) vaccine based on wild-type virus strain induces cross-protective immune responses.

The rapid spread and the transmission to humans of avian influenza virus (H5N1) have induced world-wide fears of a new pandemic and raised concerns over the ability of standard influenza vaccine production methods to rapidly supply sufficient amounts of an effective vaccine. We report here on a robust and flexible strategy which uses wild-type virus grown in a continuous cell culture (Vero) system to produce an inactivated whole virus vaccine. Candidate vaccines based on clade 1 and clade 2 influenza H5N1 strains were developed and demonstrated to be highly immunogenic in animal models.

The preclinical testing of a formaldehyde inactivated Ross River virus vaccine designed for use in humans.

Ross River virus was grown in industrial facilities in vaccine-certified Vero cells in the absence of serum, inactivated using standard formalin-inactivation protocols, treated with Benzonase to digest host cell DNA and purified on a sucrose gradient. Mice given two subcutaneous injections of 0.625 microg of this vaccine or two doses of 0.

In vitro and in vivo anti-retroviral activity of the substance purified from the aqueous extract of Chelidonium majus L.

We have isolated a substance with anti-retroviral activity from the freshly prepared crude extract of Chelidonium majus L. (greater celandine) by 9-aminoacridine precipitation method and ion exchange chromatography using Dowex-50W/H+ resin followed by the gel filtration on Sephadex-75 column. Elemental and phenol/sulfuric acid method analyses as well as the mass spectrometry of the purified substance indicated that it may represent a low-sulfated poly-glycosaminoglycan moiety with molecular weight of approximately 3800 Da.

The influence of oral L-arginine on fracture healing: an animal study.

Background: The known biological activities of nitric oxide suggest a role in bone healing. We hypothesized that L-arginine, a source of nitric oxide, expedites the healing process of stabilized diaphyseal defects.

Type Of Study: Prospective blinded animal study.

A double-inactivated whole virus candidate SARS coronavirus vaccine stimulates neutralising and protective antibody responses.

A double-inactivated, candidate whole virus vaccine against severe acute respiratory syndrome associated coronavirus (SARS-CoV) was developed and manufactured at large scale using fermenter cultures of serum protein free Vero cells. A two step inactivation procedure involving sequential formaldehyde and U.V.