Protective efficacy of DNA vaccines encoding outer membrane protein A and OmpK36 of Klebsiella pneumoniae in mice.
The immunogenicity of DNA vaccines expressing outer membrane proteins as antigens was evaluated in this study. DNA vaccines consisting of vector pVAX1 expressing either outer membrane protein A or OmpK36 were injected into mice by either the intradermal or the intramuscular route. Antibodies elicited were shown to be specifically reactive to OmpA and OmpK36 by immunoblotting. The immunoglobulin G (IgG) antibodies elicited by both vaccines included IgG1, IgG2a, IgG2b, and IgG3. Immunized mice exhibited a predominance of IgG1 over IgG2a, therefore indicating a stronger humoral response. Mice receiving either of the DNA vaccines produced high levels of interleukin-12 (IL-12) and IL-10 and low levels of gamma interferon, suggesting the induction of a mixed Th1 and Th2 response. Sera from DNA vaccine-immunized mice had significantly higher opsonic activity in opsonophagocytic assays than did sera from the control mice. The level of protection afforded by pOmpK36 DNA injected intradermally into mice was the highest. These results suggest that both OmpA and OmpK36 are excellent candidates for use in future studies of vaccination against infections caused by Klebsiella pneumoniae. This is the first study which established the efficacy of protection afforded by DNA vaccines based on outer membrane proteins against K. pneumoniae infections.
Department of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom.
Prathiba
P
Kurupati
N P
NP
Ramachandran
Chit Laa
CL
Poh
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000918:Antibody Specificity; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology*; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D005260:Female; D007114:Immunization; D007074:Immunoglobulin G / Q000097:blood; D007271:Injections, Intradermal; D007273:Injections, Intramuscular; D007710:Klebsiella Infections / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D007711:Klebsiella pneumoniae / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D018272:Porins / Q000235:genetics / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D007074:Immunoglobulin G; C092233:OmpK36 protein, Klebsiella pneumoniae; D018272:Porins; D019444:Vaccines, DNA; C078167:OMPA outer membrane proteins