Cross-Protective Potential and Protection-Relevant Immune Mechanisms of Whole Inactivated Influenza Virus Vaccines Are Determined by Adjuvants and Route of Immunization.

Adjuvanted whole inactivated virus (WIV) influenza vaccines show promise as broadly protective influenza vaccine candidates. Using WIV as basis we assessed the relative efficacy of different adjuvants by carrying out a head-to-head comparison of the liposome-based adjuvants CAF01 and CAF09 and the protein-based adjuvants CTA1-DD and CTA1-3M2e-DD and evaluated whether one or more of the adjuvants could induce broadly protective immunity. Mice were immunized with WIV prepared from A/Puerto Rico/8/34 (H1N1) virus intramuscularly with or without CAF01 or intranasally with or without CAF09, CTA1-DD, or CTA1-3M2e-DD, followed by challenge with homologous, heterologous or heterosubtypic virus.

No significant HTLV seroprevalence in German people who inject drugs.

Background: Although human T-lymphotropic virus (HTLV) is transmitted via the same routes as human immunodeficiency virus (HIV), its worldwide seroprevalence differs drastically because HTLV is transmitted mainly via infected cells rather than free virus. The sharing of needles and other equipment places people who inject drugs (PWID) at particularly high-risk for such blood-borne diseases.

Methods: To validate the methodology used to process and analyze the dried blood spots (DBS) utilized in the study, dried serum spots (DSS) with dilutions of sera from known HTLV infected individuals were analyzed by ELISA and Western blot.

Evaluation of the immunogenicity and safety of different doses and formulations of a broad spectrum influenza vaccine (FLU-v) developed by SEEK: study protocol for a single-center, randomized, double-blind and placebo-controlled clinical phase IIb trial.

Background: Current influenza vaccines, based on antibodies against surface antigens, are unable to provide protection against newly emerging virus strains which differ from the vaccine strains. Therefore the population has to be re-vaccinated annually. It is thus important to develop vaccines which induce protective immunity to a broad spectrum of influenza viruses.

Evaluating the immunogenicity and safety of a BiondVax-developed universal influenza vaccine (Multimeric-001) either as a standalone vaccine or as a primer to H5N1 influenza vaccine: Phase IIb study protocol.

Introduction: Influenza is a major respiratory viral infection of humans with high mortality and morbidity rates and profound economic impact. Although influenza vaccines are generally updated yearly to match the viruses expected in the coming season, genetic mutation and reassortment can result in unexpected novel strains. Therefore, it is important to develop universal vaccines inducing protective immunity to such strains before they appear.

Development of an antigen-capture ELISA for the detection of the p27-CA protein of HERV-K(HML-2).

The detection or quantification of retroviruses is often achieved using an antigen-capture ELISA (AC-ELISA) that targets the Gag capsid (CA) protein. We report here the development of an AC-ELISA specific for the p27-CA protein of HERV-K(HML-2). A monoclonal p27-specific antibody is used for capture and a polyclonal anti-p27-CA immune serum generated in rabbits serves for detection.

Suppressing active replication of a live attenuated simian immunodeficiency virus vaccine does not abrogate protection from challenge.

Although safety concerns preclude the use of live attenuated HIV vaccines in humans, they provide a useful system for identifying the elusive correlates of protective immunity in the SIV/macaque animal model. However, a number of pieces of evidence suggest that protection may result from prior occupancy of susceptible target cells by the vaccine virus rather than the immune response. To address this, we developed a Nef-deletion variant of an RT-SHIV whose active replication could be shut off by treatment with RT-inhibitors.

Assessment of ambiguous base calls in HIV-1 pol population sequences as a biomarker for identification of recent infections in HIV-1 incidence studies.

An increase in the proportion of ambiguous base calls in HIV-1 pol population sequences during the course of infection has been demonstrated in different study populations, and sequence ambiguity thresholds to classify infections as recent or nonrecent have been suggested. The aim of our study was to evaluate sequence ambiguities as a candidate biomarker for use in an HIV-1 incidence assay using samples from antiretroviral treatment-naive seroconverters with known durations of infection (German HIV-1 Seroconverter Study). We used 2,203 HIV-1 pol population sequences derived from 1,334 seroconverters to assess the sequence ambiguity method (SAM).

Timed action of IL-27 protects from immunopathology while preserving defense in influenza.

Infection with influenza virus can result in massive pulmonary infiltration and potentially fatal immunopathology. Understanding the endogenous mechanisms that control immunopathology could provide a key to novel adjunct therapies for this disease. Here we show that the cytokine IL-27 plays a crucial role in protection from exaggerated inflammation during influenza virus infection.

A novel small animal model to study the replication of simian foamy virus in vivo.

Preclinical evaluation in a small animal model would help the development of gene therapies and vaccines based on foamy virus vectors. The establishment of persistent, non-pathogenic infection with the prototype foamy virus in mice and rabbits has been described previously. To extend this spectrum of available animal models, hamsters were inoculated with infectious cell supernatant or bioballistically with a foamy virus plasmid.

Characterization of a monoclonal anti-capsid antibody that cross-reacts with three major primate lentivirus lineages.

Mouse monoclonal antibodies with varying specificities against the Gag capsid of simian and human immunodeficiency virus (SIV/HIV) were generated by immunizing mice with whole inactivated SIVagmTYO-1. Monoclonal antibody AG3.0 showed the broadest reactivity recognizing the Gag capsid protein (p24-27) and Gag precursors p38, p55, and p150 of HIV-1, HIV-2, SIVmac, and SIVagm.

Joint production of prime/boost pairs of Fowlpox Virus and Modified Vaccinia Ankara recombinants carrying the same transgene.

Pairs of recombinant MVA (Modified Vaccinia Ankara) and FPV (Fowlpox Virus) expressing the same transgene are reasonable candidates for prime/boost regimens, because cross-reacting immune responses between the two vectors, both non-replicative in mammalian hosts, are very limited. The acceptor virus FPD-Red, a derivative of FPV, carrying a red fluorescent protein gene flanked by the homology regions of MVA deletion III, was constructed. The same MVA Transfer Plasmid Green, designed to insert transgenes into the MVA deletion III locus, can therefore be used to transfer transgenes into both acceptor viruses MVA-Red and FPD-Red with the described recently Red-to-Green gene swapping method.

Vaccine protection against lethal homologous and heterologous challenge using recombinant AAV vectors expressing codon-optimized genes from pandemic swine origin influenza virus (SOIV).

The recent H1N1 influenza pandemic and the inevitable delay between identification of the virus and production of the specific vaccine have highlighted the urgent need for new generation influenza vaccines that can preemptively induce broad immunity to different strains of the virus. In this study we have produced AAV-based vectors expressing the A/Mexico/4603/2009 (H1N1) hemagglutinin (HA), nucleocapsid (NP) and the matrix protein M1 and have evaluated their ability to induce specific immune response and protect mice against homologous and heterologous challenge. Each of the vaccine vectors elicited potent cellular and humoral immune responses in mice.

SIVagm containing the SHIV89.6P Envelope gene replicates poorly and is non-pathogenic.

SIVagm does not induce disease in its African green monkey (AGM) host. In comparison, the hybrid simian-human immunodeficiency virus SHIV89.6P that carries the HIV env gene induces disease in rhesus macaques more rapidly than the SIVmac parent virus.

Enhanced T- and B-cell responses to simian immunodeficiency virus (SIV)agm, SIVmac and human immunodeficiency virus type 1 Gag DNA immunization and identification of novel T-cell epitopes in mice via codon optimization.

As a prelude to primate studies, the immunogenicity of wild-type and codon-optimized versions of simian immunodeficiency virus (SIV)agm Gag DNA, with and without co-administered granulocyte-macrophage colony-stimulating factor (GM-CSF) DNA, was directly compared in two strains of mice. Gag-specific T cells in the splenocytes of BALB/c and C57BL/6 mice immunized by gene gun were quantified by ELISpot using panels of overlapping synthetic peptides (15mers) spanning the entire capsid proteins of SIVagm, SIVmac and human immunodeficiency virus type 1. Specific antibodies were measured by ELISA.

Role of complement and antibodies in controlling infection with pathogenic simian immunodeficiency virus (SIV) in macaques vaccinated with replication-deficient viral vectors.

Background: We investigated the interplay between complement and antibodies upon priming with single-cycle replicating viral vectors (SCIV) encoding SIV antigens combined with Adeno5-SIV or SCIV pseudotyped with murine leukemia virus envelope boosting strategies. The vaccine was applied via spray-immunization to the tonsils of rhesus macaques and compared with systemic regimens.

Results: Independent of the application regimen or route, viral loads were significantly reduced after challenge with SIVmac239 (p < 0.

Accelerated prion replication in, but prolonged survival times of, prion-infected CXCR3-/- mice.

Prion diseases have a significant inflammatory component. Glia activation, which is associated with increased production of cytokines and chemokines, may play an important role in disease development. Among the chemokines upregulated highly and early upregulated during scrapie infections are ligands of CXCR3.

Characterization of a chemokine receptor CCR5-negative T cell line and its use in determining human immunodeficiency virus type 1 phenotype.

A human CD4-positive T cell line from a donor homozygous negative for the chemokine receptor CCR5 was established, characterized, and used for determining the coreceptor usage of human immunodeficiency virus type 1 (HIV-1) isolates. Clones of this IL-2 dependent human T-cell lymphotropic virus type 1 (HTLV-I) immortalized cell line, named IsnoR5 clones 1 and 2, are susceptible to infection by HIV-1 isolates that use CXCR4 as a coreceptor but resistant to infection by CCR5 tropic HIV-1 viruses. HIV-1 isolates whose replication is inhibited in IsnoR5 cells in the presence of the bicyclam AMD 3100, a CXCR4 specific inhibitor, utilize a coreceptor distinct from CCR5 and CXCR4.

Atraumatic oral spray immunization with replication-deficient viral vector vaccines.

The development of needle-free vaccines is one of the recently defined "grand challenges in global health" (H. Varmus, R. Klausner, R.

Sustained conservation of CD4+ T cells in multiprotein triple modality-immunized rhesus macaques after intrarectal challenge with simian immunodeficiency virus.

As part of a European multicenter study designed to determine the optimal combination and order of a mixed-modality vaccine against acquired immunodeficiency syndrome, rhesus monkeys received a combination of three different vectors, all expressing the same Simian Immunodeficiency Virus (SIV) genes followed by mucosal challenge with highly pathogenic SIV. In the study reported here, animals were primed with DNA followed by one booster immunization with Semliki Forest Virus (SFV) and two immunizations with modified Vaccinia Ankara (MVA). To address the relevance of mucosal immunization, we compared systemic versus a combination of systemic and mucosal antigen application.

Retroviral vectors for vaccine development: induction of HIV-1-specific humoral and cellular immune responses in rhesus macaques using a novel MLV(HIV-1) pseudotype vector.

Retroviral vectors have yet not been tested for their potential as vaccines despite their frequent utilization in gene therapy allowing for highly efficient gene transfer into a number of cell types and their suitability for large-scale production in biotechnology. To investigate MLV-based vectors suitability for inducing immune response against HIV-1-antigens, we generated a MLV(HIV-1) pseudotype vector enabling CD4-specific transduction of HIV-1 genes env, vpu, tat and rev originating from the pathogenic SHIV-89.6P.

Reduction of viral loads by multigenic DNA priming and adenovirus boosting in the SIVmac-macaque model.

In this study, we investigated the ability of a multigenic SIV DNA prime/replication-defective adenovirus serotype 5 (rAd/SIV) boost regimen to induce SIV-specific immune responses and protection against intrarectal challenge with SIVmac251 in rhesus macaques. Four rhesus macaques were immunized intramuscularly three times at 8-week intervals with SIV DNA vaccine and boosted once with rAd/SIV vaccine Four control macaques received the same amount of mock plasmid DNA and mock adenovirus vector. While the SIV DNA vaccine included plasmids expressing a mutated human IL-12 gene (IL-12N222L) as well as SIVmac239 structural and regulatory genes, the rAd/SIV vaccine contained rAd vectors expressing SIVmac239 genes only.

T-cell-mediated protective efficacy of a systemic vaccine approach in cynomolgus monkeys after SIV mucosal challenge.

The immunogenicity and the protective efficacy of a new polyvalent triple vector (DNA/SFV/MVA) based vaccine against mucosal challenge with pathogenic SIVmac251 were investigated. Cynomolgus monkeys (Macaca fascicularis) were primed intradermally with DNA, boosted twice subcutaneously with recombinant Semliki Forest virus (rSFV) and finally intramuscularly with recombinant Modified Vaccinia Virus Ankara strain (rMVA). Both DNA and recombinant viral vectors expressed SIV proteins (Gag, Pol, Tat, Rev, Nef and Env).

Protective efficacy of a multicomponent vector vaccine in cynomolgus monkeys after intrarectal simian immunodeficiency virus challenge.

We investigated the protective efficacy of a systemic triple vector (DNA/rSFV/rMVA)-based vaccine against mucosal challenge with pathogenic simian immunodeficiency virus (SIV) in cynomolgus monkeys. Animals were immunized at week 0 with DNA (intradermally), at weeks 8 and 16 with recombinant Semliki Forest virus (rSFV, subcutaneously) and finally, at week 24, with recombinant modified vaccinia virus Ankara strain (rMVA, intramuscularly). Both DNA and recombinant viral vectors expressed a wide range of SIV proteins (Gag, Pol, Tat, Rev, Env and Nef).

The role of the immune response during SIVagm infection of the African green monkey natural host.

The African green monkey (AGM) is one of many African species endemically infected with simian immunodeficiency virus (SIV). Like the other natural hosts, AGMs do not succumb to AIDS and understanding the basis for this resistance to disease progression would be of enormous theoretical and practical importance. Early efforts by our group that concentrated on identifying immune mechanisms presumed to keep the virus under control failed to find any obvious candidates.

PDZ Domain-mediated interaction of interleukin-16 precursor proteins with myosin phosphatase targeting subunits.

The cytokine interleukin-16 is generated by posttranscriptional cleavage by caspase-3 of two large precursor isoforms. The smaller protein of 67 kDa (pro-IL-16) is expressed in cells of the immune system and contains three PDZ (postsynaptic density/disc large/zona occludens-1) domains, whereas the larger 141-kDa neuronal variant (npro-IL-16) has two additional PDZ domains in its N-terminal extension that interact with neuronal ion channels. Using the yeast two-hybrid approach we have identified three closely related myosin phosphatase targeting subunits, MYPT1, MYPT2, and MBS85, as binding partners of the IL-16 precursor proteins.