title: Matrix-M™ adjuvation broadens protection induced by seasonal trivalent virosomal influenza vaccine.
abstract: BACKGROUND
  Influenza virus infections are responsible for significant morbidity worldwide and therefore it remains a high priority to develop more broadly protective vaccines. Adjuvation of current seasonal influenza vaccines has the potential to achieve this goal.
  
  
  METHODS
  To assess the immune potentiating properties of Matrix-M™, mice were immunized with virosomal trivalent seasonal vaccine adjuvated with Matrix-M™. Serum samples were isolated to determine the hemagglutination inhibiting (HAI) antibody titers against vaccine homologous and heterologous strains. Furthermore, we assess whether adjuvation with Matrix-M™ broadens the protective efficacy of the virosomal trivalent seasonal vaccine against vaccine homologous and heterologous influenza viruses.
  
  
  RESULTS
  Matrix-M™ adjuvation enhanced HAI antibody titers and protection against vaccine homologous strains. Interestingly, Matrix-M™ adjuvation also resulted in HAI antibody titers against heterologous influenza B strains, but not against the tested influenza A strains. Even though the protection against heterologous influenza A was induced by the adjuvated vaccine, in the absence of HAI titers the protection was accompanied by severe clinical scores and body weight loss. In contrast, in the presence of heterologous HAI titers full protection against the heterologous influenza B strain without any disease symptoms was obtained.
  
  
  CONCLUSIONS
  The results of this study emphasize the promising potential of a Matrix-M™-adjuvated seasonal trivalent virosomal influenza vaccine. Adjuvation of trivalent virosomal vaccine does not only enhance homologous protection, but in addition induces protection against heterologous strains and thus provides overall more potent and broad protective immunity.
authors.affiliation: Present Address: Infectious Diseases and Vaccines Therapeutic area, Janssen Research and Development, Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. FCox@its.jnj.com.
authors.forename: Freek
authors.initials: F
authors.lastname: Cox
authors.affiliation: Present Address: Infectious Diseases and Vaccines Therapeutic area, Janssen Research and Development, Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. Esaeland@its.jnj.com.
authors.forename: Eirikur
authors.initials: E
authors.lastname: Saeland
authors.affiliation: Present Address: Infectious Diseases and Vaccines Therapeutic area, Janssen Research and Development, Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. MBaart@its.jnj.com.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Baart
authors.affiliation: Present Address: Janssen Prevention Center, Center of Excellence of Janssen Research & Development, Janssen Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. MKoldijk@its.jnj.com.
authors.forename: Martin
authors.initials: M
authors.lastname: Koldijk
authors.affiliation: Present Address: Infectious Diseases and Vaccines Therapeutic area, Janssen Research and Development, Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. JTolboom@its.jnj.com.
authors.forename: Jeroen
authors.initials: J
authors.lastname: Tolboom
authors.affiliation: Present Address: Infectious Diseases and Vaccines Therapeutic area, Janssen Research and Development, Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. LDekking@its.jnj.com.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Dekking
authors.affiliation: Present Address: Janssen Prevention Center, Center of Excellence of Janssen Research & Development, Janssen Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. WKoudsta@its.jnj.com.
authors.forename: Wouter
authors.initials: W
authors.lastname: Koudstaal
authors.affiliation: Present Address: Novavax AB, Uppsala, Sweden. KLovgren@Novavax.com.
authors.forename: Karin
authors.initials: K
authors.lastname: Lövgren Bengtsson
authors.affiliation: Present Address: Janssen Prevention Center, Center of Excellence of Janssen Research & Development, Janssen Pharmaceutical companies of Johnson and Johnson, Leiden, The Netherlands. JGoudsmi@its.jnj.com.
authors.forename: Jaap
authors.initials: J
authors.lastname: Goudsmit
authors.affiliation: Present Address: Sanofi, Global Biotherapeutics, Vitry-sur-Seine, France. K_Radosevic@hotmail.com.
authors.forename: Katarina
authors.initials: K
authors.lastname: Radošević
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001835:Body Weight; D005260:Female; D006385:Hemagglutination Inhibition Tests; D064789:Immunity, Heterologous; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D008807:Mice, Inbred BALB C; D009975:Orthomyxoviridae / Q000235:genetics / Q000276:immunology*; D009976:Orthomyxoviridae Infections / Q000473:pathology / Q000517:prevention & control; D012720:Severity of Illness Index; D058425:Vaccines, Virus-Like Particle / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D007252:Influenza Vaccines; D058425:Vaccines, Virus-Like Particle