title: Systemic antibody response to nano-size calcium phospate biocompatible adjuvant adsorbed HEV-71 killed vaccine.
abstract: OBJECTIVE
  Since 1980s, human enterovirus-71 virus (HEV-71) is one of the common infectious disease in Asian Pacific region since late 1970s without effective commercial antiviral or protective vaccine is unavailable yet. The work examines the role of vaccine adjuvant particle size and the route of administration on postvaccination antibody response towards HEV-71 vaccine adsorbed to calcium phosphate (CaP) adjuvant.
  
  
  METHODS
  First, CaP nano-particles were compared to a commercial micro-size and vaccine alone. Secondly, intradermal reduced dosage was compared to the conventional intramuscular immunization. Killed HEV-71 vaccines adsorbed to CaP nano-size (73 nm) and commercial one of micro-size (1.7 µm) were administered through intradermal, intramuscular, rabbits received vaccine alone and unvaccinated animals.
  
  
  RESULTS
  CaP nano-particles adsorbed HEV-71 vaccine displayed higher antibody than the micro-size or unadsorbed vaccine alone, through both parenteral immunization routes. Moreover, the intradermal route (0.5 µg/mL) of 0.1-mL volume per vaccine dose induced equal IgG antibody level to 1.0-mL intramuscular route (0.5 µg/mL).
  
  
  CONCLUSIONS
  The intradermal vaccine adsorbed CaP nano-adjuvant showed safer and significant antibody response after one-tenth reduced dose quantity (0.5 µg/mL) of only 0.1-mL volume as the most suitable protective, cost effective and affordable formulation not only for HEV-71; but also for developing further effective vaccines toward other human pathogens.
authors: Department of Microbiology and Parasitology, University of Putra Malaysia, Medical Faculty, Serdang, Malaysia.
authors: Mohamed Ibrahim
authors: 0000-0002-3530-1351
authors: MI
authors: Saeed
authors: University of Putra Malaysia, Institute of Biosciences, Serdang, Malaysia.
authors: Abd Rahaman
authors: 0000-0001-7379-0507
authors: AR
authors: Omar
authors: University of Putra Malaysia, Institute of Advanced Technology, Serdang, Malaysia.
authors: Mohd Zobir
authors: 0000-0002-0741-261X
authors: MZ
authors: Hussein
authors: Department of Microbiology and Parasitology, University of Khartoum, Faculty of Medicine, Sudan, Malaysia.
authors: Isam Mohamed
authors: 0000-0003-1451-235X
authors: IM
authors: Elkhidir
authors: Department of Microbiology and Parasitology, University of Putra Malaysia, Medical Faculty, Serdang, Malaysia.
authors: Zamberi
authors: 0000-0001-1755-2013
authors: Z
authors: Sekawi
keywords: Adjuvanted vaccine; Calcium phosphate; Human enterovirus 71; Intradermal injections; Nanoparticles
references: Epidemiol Infect. 2010 Aug;138(8):1071-89
references: 20056019
references: J Clin Microbiol. 2009 Nov;47(11):3653-62
references: 19776232
references: PLoS Negl Trop Dis. 2012;6(8):e1737
references: 22953003
references: J Gen Virol. 2010 Aug;91(Pt 8):1949-58
references: 20375223
references: J Clin Microbiol. 2009 Jul;47(7):2351-2
references: 19439545
references: Vaccine. 2011 Jun 10;29(26):4362-72
references: 21501643
references: Expert Rev Vaccines. 2007 Oct;6(5):797-808
references: 17931159
references: Virus Res. 2008 Feb;131(2):250-9
references: 18036697
references: J Virol. 1982 Jan;41(1):340-4
references: 6283126
references: Expert Rev Vaccines. 2010 Feb;9(2):149-56
references: 20109026
references: Vaccine. 2008 Mar 28;26(15):1855-62
references: 18329759
references: Virus Res. 2007 Apr;125(1):61-8
references: 17222936
references: BMC Infect Dis. 2011 Jul 18;11:197
references: 21767352
references: Expert Opin Drug Saf. 2003 May;2(3):225-31
references: 12904102
references: Infect Genet Evol. 2010 Apr;10(3):404-12
references: 19465162
references: Vaccine. 2012 Jan 17;30(4):703-11
references: 22142585
references: Virol J. 2011 Jun 16;8:306
references: 21679417
references: FEMS Microbiol Rev. 2002 Mar;26(1):91-107
references: 12007645
references: Vaccine. 2006 Apr 5;24(15):2944-51
references: 16448730
references: Arch Virol. 2011 Jun;156(6):945-53
references: 21305327
references: Vaccine. 2001 Dec 12;20(5-6):895-904
references: 11738755
references: J Infect Dis. 1997 Jan;175(1):16-25
references: 8985191
references: Vaccine. 2011 Jun 24;29(29-30):4829-38
references: 21550375
references: J Infect Dis. 2003 May 15;187(10):1562-70
references: 12721936
references: Scand J Infect Dis. 2012 Apr;44(4):297-305
references: 22176514