Bovine Herpesvirus Type 1 (BHV-1) UL49.5 Luminal Domain Residues 30 to 32 Are Critical for MHC-I Down-Regulation in Virus-Infected Cells

Bovine herpesvirus type 1 (BHV-1) UL49.5 inhibits transporter associated with antigen processing (TAP) and down-regulates cell-surface expression of major histocompatibility complex (MHC) class I molecules to promote immune evasion. We have constructed a BHV-1 UL49.5 cytoplasmic tail (CT) null and several UL49.5 luminal domain mutants in the backbone of wild-type BHV-1 or BHV-1 UL49.5 CT- null viruses and determined their relative TAP mediated peptide transport inhibition and MHC-1 down-regulation properties compared with BHV-1 wt. Based on our results, the UL49.5 luminal domain residues 30–32 and UL49.5 CT residues, together, promote efficient TAP inhibition and MHC-I down-regulation functions. In vitro, BHV-1 UL49.5 Δ30–32 CT-null virus growth property was similar to that of BHV-1 wt and like the wt UL49.5, the mutant UL49.5 was incorporated in the virion envelope and it formed a complex with gM in the infected cells

Immunogenicity and Protective Capacity of a Virosomal Respiratory Syncytial Virus Vaccine Adjuvanted with Monophosphoryl Lipid A in Mice

Respiratory Syncytial Virus (RSV) is a major cause of viral brochiolitis in infants and young children and is also a significant problem in elderly and immuno-compromised adults. To date there is no efficacious and safe RSV vaccine, partially because of the outcome of a clinical trial in the 1960s with a formalin-inactivated RSV vaccine (FI-RSV). This vaccine caused enhanced respiratory disease upon exposure to the live virus, leading to increased morbidity and the death of two children. Subsequent analyses of this incident showed that FI-RSV induces a Th2-skewed immune response together with poorly neutralizing antibodies. As a new approach, we used reconstituted RSV viral envelopes, i.e. virosomes, with incorporated monophosphoryl lipid A (MPLA) adjuvant to enhance immunogenicity and to skew the immune response towards a Th1 phenotype. Incorporation of MPLA stimulated the overall immunogenicity of the virosomes compared to non-adjuvanted virosomes in mice. Intramuscular administration of the vaccine led to the induction of RSV-specific IgG2a levels similar to those induced by inoculation of the animals with live RSV. These antibodies were able to neutralize RSV in vitro. Furthermore, MPLA-adjuvanted RSV virosomes induced high amounts of IFNγ and low amounts of IL5 in both spleens and lungs of immunized and subsequently challenged animals, compared to levels of these cytokines in animals vaccinated with FI-RSV, indicating a Th1-skewed response. Mice vaccinated with RSV-MPLA virosomes were protected from live RSV challenge, clearing the inoculated virus without showing signs of lung pathology. Taken together, these data demonstrate that RSV-MPLA virosomes represent a safe and efficacious vaccine candidate which warrants further evaluation

DNA vaccination for prostate cancer: key concepts and considerations

While locally confined prostate cancer is associated with a low five year mortality rate, advanced or metastatic disease remains a major challenge for healthcare professionals to treat and is usually terminal. As such, there is a need for the development of new, efficacious therapies for prostate cancer. Immunotherapy represents a promising approach where the host’s immune system is harnessed to mount an anti-tumour effect, and the licensing of the first prostate cancer specific immunotherapy in 2010 has opened the door for other immunotherapies to gain regulatory approval. Among these strategies DNA vaccines are an attractive option in terms of their ability to elicit a highly specific, potent and wide-sweeping immune response. Several DNA vaccines have been tested for prostate cancer and while they have demonstrated a good safety profile they have faced problems with low efficacy and immunogenicity compared to other immunotherapeutic approaches. This review focuses on the positive aspects of DNA vaccines for prostate cancer that have been assessed in preclinical and clinical trials thus far and examines the key considerations that must be employed to improve the efficacy and immunogenicity of these vaccines

Nucleoprotein Nanostructures Combined with Adjuvants Adapted to the Neonatal Immune Context: A Candidate Mucosal RSV Vaccine

BACKGROUND: The human respiratory syncytial virus (hRSV) is the leading cause of severe bronchiolitis in infants worldwide. The most severe RSV diseases occur between 2 and 6 months-of-age, so pediatric vaccination will have to be started within the first weeks after birth, when the immune system is prone to Th2 responses that may turn deleterious upon exposure to the virus. So far, the high risk to prime for immunopathological responses in infants has hampered the development of vaccine. In the present study we investigated the safety and efficacy of ring-nanostructures formed by the recombinant nucleoprotein N of hRSV (N(SRS)) as a mucosal vaccine candidate against RSV in BALB/c neonates, which are highly sensitive to immunopathological Th2 imprinting. METHODOLOGY AND PRINCIPAL FINDINGS: A single intranasal administration of N(SRS) with detoxified E. coli enterotoxin LT(R192G) to 5-7 day old neonates provided a significant reduction of the viral load after an RSV challenge at five weeks of age. However, neonatal vaccination also generated an enhanced lung infiltration by neutrophils and eosinophils following the RSV challenge. Analysis of antibody subclasses and cytokines produced after an RSV challenge or a boost administration of the vaccine suggested that neonatal vaccination induced a Th2 biased local immune memory. This Th2 bias and the eosinophilic reaction could be prevented by adding CpG to the vaccine formulation, which, however did not prevent pulmonary inflammation and neutrophil infiltration upon viral challenge. CONCLUSIONS/SIGNIFICANCE: In conclusion, protective vaccination against RSV can be achieved in neonates but requires an appropriate combination of adjuvants to prevent harmful Th2 imprinting

Sub-Nucleocapsid Nanoparticles: A Nasal Vaccine against Respiratory Syncytial Virus

Background: Bronchiolitis caused by the respiratory syncytial virus (RSV) in infants less than two years old is a growing public health concern worldwide, and there is currently no safe and effective vaccine. A major component of RSV nucleocapsid, the nucleoprotein (N), has been so far poorly explored as a potential vaccine antigen, even though it is a target of protective anti-viral T cell responses and is remarkably conserved between human RSV A and B serotypes. We recently reported a method to produce recombinant N assembling in homogenous rings composed of 10–11 N subunits enclosing a bacterial RNA. These nanoparticles were named sub-nucleocapsid ring structure (N SRS). Methodology and Principal Findings: The vaccine potential of N SRS was evaluated in a well-characterized and widely acknowledged mouse model of RSV infection. BALB/c adult mice were immunized intranasally with N SRS adjuvanted with the detoxified E. coli enterotoxin LT(R192G). Upon RSV challenge, vaccinated mice were largely protected against virus replication in the lungs, with a mild inflammatory lymphocytic and neutrophilic reaction in their airways. Mucosal immunization with N SRS elicited strong local and systemic immunity characterized by high titers of IgG1, IgG2a and IgA anti-N antibodies, antigen-specific CD8+ T cells and IFN-c-producing CD4+ T cells. Conclusions/Significance: This is the first report of using nanoparticles formed by the recombinant nucleocapsid protein as an efficient and safe intra-nasal vaccine against RSV

Calf health from birth to weaning. III. housing and management of calf pneumonia

Calfhood diseases have a major impact on the economic viability of cattle operations. A three part review series has been developed focusing on calf health from birth to weaning. In this paper, the last of the three part series, we review disease prevention and management with particular reference to pneumonia, focusing primarily on the pre-weaned calf. Pneumonia in recently weaned suckler calves is also considered, where the key risk factors are related to the time of weaning. Weaning of the suckler calf is often combined with additional stressors including a change in nutrition, environmental change, transport and painful husbandry procedures (castration, dehorning). The reduction of the cumulative effects of these multiple stressors around the time of weaning together with vaccination programmes (preconditioning) can reduce subsequent morbidity and mortality in the feedlot. In most studies, calves housed individually and calves housed outdoors with shelter, are associated with decreased risk of disease. Even though it poses greater management challenges, successful group housing of calves is possible. Special emphasis should be given to equal age groups and to keeping groups stable once they are formed. The management of pneumonia in calves is reliant on a sound understanding of aetiology, relevant risk factors, and of effective approaches to diagnosis and treatment. Early signs of pneumonia include increased respiratory rate and fever, followed by depression. The single most important factor determining the success of therapy in calves with pneumonia is early onset of treatment, and subsequent adequate duration of treatment. The efficacy and economical viability of vaccination against respiratory disease in calves remains unclear

Inhibition of bovine sperm-zona binding by bovine herpesvirus-1

The purpose of the present study was to identify a potential interference of bovine herpesvirus-1 (BoHV-1) with sperm-oocyte interactions during bovine in vitro fertilization. An inhibition of almost 70% of sperm-zona binding was observed when bovine cumulus-denuded oocytes were inseminated in the presence of 10(7) 50% tissue culture infective dose/ml BoHV-1. The inhibitory effect of BoHV-1 on sperm-zona binding was mediated by an interaction of the virus with spermatozoa, but not with oocytes. Treatment of spermatozoa with BoHV-1, however, did not affect sperm motility and acrosomal status. Antiserum against RoHV-1 prevented the virus-induced inhibition of sperm-zona binding, indicating that BoHV-1 itself affects the fertilization process. In order to investigate which BoHV-1 glycoprotein(s) are responsible for the virus-sperm interaction, BoHV-1 was treated with monoclonal antibodies against the viral glycoproteins gB, gC, gD and gH prior to insemination. Anti-gC completely prevented the inhibitory effect of BoHV-1 on sperm-zona binding, while anti-gD caused a reduction of this inhibition. Further evidence for the involvement of gC and gD in the virus-sperm interaction was provided by the fact that purified gC and gD decreased sperm-zona binding in a dose-dependent way with gC being more effective than gD. These results indicated that BoHV-1 inhibits bovine sperm-zona binding by interacting with spermatozoa. The binding of BoHV-1 to a spermatozoon is mediated by the viral glycoproteins gC and gD, and therefore seems to be comparable with the mechanisms of BoHV-1 attachment to its natural host cell