title: Higher memory responses in HIV-infected and kidney transplanted patients than in healthy subjects following priming with the pandemic vaccine.
abstract: BACKGROUND
  Memory responses require immune competence. We assessed the influence of priming with AS03-adjuvanted pandemic vaccine (Pandemrix®) on memory responses of HIV patients, kidney recipients (SOT) and healthy controls (HC).
  
  
  METHODS
  Participants (HIV: 197, SOT: 53; HC: 156) were enrolled in a prospective study and 390/406 (96%) completed it. All had been primed in 2009/2010 with 1 (HC) or 2 (patients) doses of Pandemrix®, and were boosted with the 2010/2011 seasonal influenza vaccine. Geometric mean titres and seroprotection rates were measured 12 months after priming and 4 weeks after boosting. Primary and memory responses were directly compared in 191 participants (HCW: 69, HIV: 71, SOT: 51) followed during 2 consecutive seasons.
  
  
  RESULTS
  Most participants (HC: 77.8%, HIV: 77.6%, SOT: 66%) remained seroprotected at 12 months post-priming. Persisting A/09/H1N1 titers were high in HIV (100.2) and HC (120.1), but lower in SOT (61.4) patients. Memory responses reached higher titers in HIV (507.8) than in HC (253.5) and SOT (136.9) patients. Increasing age and lack of HAART reduced persisting and memory responses, mainly influenced by residual antibody titers. Comparing 2009/2010 and 2010/2011 titers in 191 participants followed for 2 seasons indicated lower post-2010/2011 titers in HC (240.2 vs 313.9), but higher titers in HIV (435.7 vs 338.0) and SOT (136 vs 90.3) patients.
  
  
  CONCLUSIONS
  Priming with 2 doses of Pandemrix® elicited persistent antibody responses and even stronger memory responses to non-adjuvanted seasonal vaccine in HIV patients than 1 dose in healthy subjects. Adjuvanted influenza vaccines may improve memory responses of immunocompromised patients.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT01022905.
authors: Department of Pathology-Immunology and Paediatrics, Centre for Vaccinology, University Hospitals of Geneva and Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors: Claire-Anne
authors: CA
authors: Siegrist
authors: Christian
authors: C
authors: van Delden
authors: Michael
authors: M
authors: Bel
authors: Christophe
authors: C
authors: Combescure
authors: Cécile
authors: C
authors: Delhumeau
authors: Matthias
authors: M
authors: Cavassini
authors: Olivier
authors: O
authors: Clerc
authors: Sara
authors: S
authors: Meier
authors: Karine
authors: K
authors: Hadaya
authors: Paola M
authors: PM
authors: Soccal
authors: Sabine
authors: S
authors: Yerly
authors: Laurent
authors: L
authors: Kaiser
authors: Bernard
authors: B
authors: Hirschel
authors: Alexandra
authors: A
authors: Calmy
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000276:immunology*; D006801:Humans; D016867:Immunocompromised Host; D007156:Immunologic Memory / Q000187:drug effects*; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000097:blood / Q000276:immunology / Q000517:prevention & control*; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D058873:Pandemics
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines; C556153:pandemrix