Immunization of mice with combinations of pneumococcal virulence proteins elicits enhanced protection against challenge with Streptococcus pneumoniae.
The vaccine potential of a combination of three pneumococcal virulence proteins was evaluated in an active-immunization-intraperitoneal-challenge model in BALB/c mice, using very high challenge doses of Streptococcus pneumoniae. The proteins evaluated were a genetic toxoid derivative of pneumolysin (PdB), pneumococcal surface protein A (PspA), and a 37-kDa metal-binding lipoprotein referred to as PsaA. Mice immunized with individual proteins or combinations thereof were challenged with high doses of virulent type 2 or type 4 pneumococci. The median survival times for mice immunized with combinations of proteins, particularly PdB and PspA, were significantly longer than those for mice immunized with any of the antigens alone. A similar effect was seen in a passive protection model. Thus, combinations of pneumococcal proteins may provide the best non-serotype-dependent protection against S. pneumoniae.
Ogunniyi
A D
AD
Molecular Microbiology Unit, Women's and Children's Hospital, North Adelaide, SA 5006, Australia.
Folland
R L
RL
Briles
D E
DE
Hollingshead
S K
SK
Paton
J C
JC
D018829:Adhesins, Bacterial; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology* / Q000302:isolation & purification; D001426:Bacterial Proteins / Q000276:immunology* / Q000302:isolation & purification; D002352:Carrier Proteins / Q000276:immunology* / Q000302:isolation & purification; D007116:Immunization, Passive / Q000379:methods; D008074:Lipoproteins / Q000276:immunology* / Q000302:isolation & purification; D008297:Male; D026901:Membrane Transport Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D011008:Pneumococcal Infections / Q000517:prevention & control*; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000302:isolation & purification; D013296:Streptococcus pneumoniae / Q000276:immunology; D013301:Streptolysins / Q000276:immunology* / Q000302:isolation & purification; D014611:Vaccination / Q000379:methods; D014774:Virulence
D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D002352:Carrier Proteins; D008074:Lipoproteins; D026901:Membrane Transport Proteins; C085000:PsaA protein, Streptococcus; D011993:Recombinant Fusion Proteins; D013301:Streptolysins; C032290:plY protein, Streptococcus pneumoniae; C051592:pneumococcal surface protein A