title: Comparison of a novel microcrystalline tyrosine adjuvant with aluminium hydroxide for enhancing vaccination against seasonal influenza.
abstract: Vaccination against seasonal influenza strains is recommended for "high risk" patient groups such as infants, elderly and those with respiratory or circulatory diseases. However, efficacy of the trivalent influenza vaccine (TIV) is poor in many cases and in the event of an influenza pandemic, mono-valent vaccines have been rapidly developed and deployed. One of the main issues with use of vaccine in pandemic situations is the lack of a suitable quantity of vaccine early enough during the pandemic to exert a major influence on the transmission of virus and disease outcome. One approach is to use a dose-sparing regimen which inevitably involves enhancing the efficacy using adjuvants.
  
  
  
  In this study we compare the use of a novel microcrystalline tyrosine (MCT) adjuvant, which is currently used in a niche area of allergy immunotherapy, for its ability to enhance the efficacy of a seasonal TIV preparation. The efficacy of the MCT adjuvant formulation was compared to alum adjuvanted TIV and to TIV administered without adjuvant using a ferret challenge model to determine vaccine efficacy.
  
  
  
  The MCT was found to possess high protein-binding capacity. In the two groups where TIV was formulated with adjuvant, the immune response was found to be higher (as determined by HAI titre) than vaccine administered without adjuvant and especially so after challenge with a live influenza virus. Vaccinated animals exhibited lower viral loads (as determined using RT-PCR) than control animals where no vaccine was administered.
  
  
  
  The attributes of each adjuvant in stimulating single-dose protection against a poorly immunogenic vaccine was demonstrated. The properties of MCT that lead to the reported effectiveness warrants further exploration in this and other vaccine targets - particularly where appropriate immunogenic, biodegradable and stable alternative adjuvants are sought.
authors.affiliation: Allergy Therapeutics Ltd, Dominion Way, West Sussex, BN14 8SA, UK. matthew.heath@allergytherapeutics.com.
authors.forename: M D
authors.initials: MD
authors.lastname: Heath
authors.affiliation: Allergy Therapeutics Ltd, Dominion Way, West Sussex, BN14 8SA, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Swan
authors.affiliation: Public Health England, PHE Porton, Porton Down, Salisbury, SP4 0JG, UK.
authors.forename: A C
authors.initials: AC
authors.lastname: Marriott
authors.affiliation: Public Health England, PHE Porton, Porton Down, Salisbury, SP4 0JG, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Silman
authors.affiliation: Public Health England, PHE Porton, Porton Down, Salisbury, SP4 0JG, UK.
authors.forename: B
authors.initials: B
authors.lastname: Hallis
authors.affiliation: Public Health England, PHE Porton, Porton Down, Salisbury, SP4 0JG, UK.|Present address: Kings College, Guys Campus, London, SE1 3QD, UK.
authors.forename: C
authors.initials: C
authors.lastname: Prevosto
authors.affiliation: Public Health England, PHE Porton, Porton Down, Salisbury, SP4 0JG, UK.
authors.forename: K E
authors.initials: KE
authors.lastname: Gooch
authors.affiliation: Allergy Therapeutics Ltd, Dominion Way, West Sussex, BN14 8SA, UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Skinner
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000536:Aluminum Hydroxide / Q000008:administration & dosage*; D000818:Animals; D003460:Crystallization; D004285:Dogs; D004339:Drug Compounding; D004357:Drug Synergism; D005289:Ferrets; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage; D007251:Influenza, Human / Q000517:prevention & control*; D061985:Madin Darby Canine Kidney Cells; D008863:Microspheres; D009976:Orthomyxoviridae Infections / Q000517:prevention & control*; D012621:Seasons; D014443:Tyrosine / Q000008:administration & dosage* / Q000737:chemistry; D014611:Vaccination / Q000379:methods*
chemical_list: D000276:Adjuvants, Immunologic; D007252:Influenza Vaccines; D014443:Tyrosine; D000536:Aluminum Hydroxide
keywords: Adjuvant; Aluminum; Ferret; Influenza; Microcrystalline tyrosine; Vaccine