Passive protection against lethal enterovirus 71 infection in newborn mice by neutralizing antibodies elicited by a synthetic peptide.
Enterovirus 71 (EV71) infections could lead to high mortalities and neither vaccine nor therapeutic treatment is available. We investigated vaccination with a synthetic peptide SP70 representing a neutralizing linear VP1 epitope of EV71 strain 41 (subgenogroup B4) and passive transfer of anti-SP70 antibodies to protect suckling Balb/c mice against EV71 infectivity. When the mouse anti-SP70 antisera with a neutralizing antibody titer of 1:32 were passively administered to one-day-old suckling mice which had been challenged with a lethal dose of 1000 TCID(50) per mouse, the neutralizing anti-SP70 antibodies were able to confer 80% in vivo protection. In contrast, suckling mice which did not receive any anti-SP70 antisera did not survive the viral challenge at day 21 postinfection. Histological examination and real-time RT-PCR assays revealed viral infiltration in small intestines of EV71-infected mice. Interestingly, anti-SP70 antibodies play a major role in the inhibition of EV71 replication in vivo and significantly reduced the viral titer. In conclusion, EV71-neutralizing antibodies elicited by the synthetic peptide SP70 were able to confer good in vivo passive protection against homologous and heterologous EV71 strains in suckling Balb/c mice.
Foo
Damian Guang Wei
DG
Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, MD4A, 5 Science Drive 2, Singapore 117597, Singapore.
Alonso
Sylvie
S
Chow
Vincent Tak Kwong
VT
Poh
Chit Laa
CL
D000818:Animals; D000914:Antibodies, Viral / Q000627:therapeutic use*; D029821:Enterovirus A, Human / Q000276:immunology*; D004769:Enterovirus Infections / Q000517:prevention & control*; D000939:Epitopes / Q000276:immunology; D007116:Immunization, Passive; D007421:Intestine, Small / Q000473:pathology / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests; D016133:Polymerase Chain Reaction; D016019:Survival Analysis; D014614:Vaccines, Synthetic / Q000276:immunology
D000914:Antibodies, Viral; D000939:Epitopes; D014614:Vaccines, Synthetic