Protective immunity to pseudomonas aeruginosa induced with a capsid-modified adenovirus expressing P. aeruginosa OprF.
This study focuses on the development of a new clinical vaccine candidate (AdOprF.RGD.Epi8) against Pseudomonas aeruginosa using an E1(-) E3(-) adenovirus (Ad) vector expressing OprF (AdOprF.RGD.Epi8) and modifications of the Ad genome providing two capsid changes: (i) modification of the Ad hexon gene to incorporate an immune-dominant OprF epitope (Epi8) into loop 1 of the hexon, enabling repeat administration to boost the anti-OprF immune response, and (ii) modification of the fiber gene to incorporate an integrin-binding RGD sequence to enhance gene delivery to antigen-presenting cells. Western analysis confirmed that AdOprF.RGD.Epi8 expresses OprF, contains Epi8 in the hexon protein, and enhances gene transfer to dendritic cells compared to AdOprF, a comparable Ad vector expressing OprF with an unmodified capsid. Intramuscular immunization of C57BL/6 mice with AdOprF.RGD.Epi8 resulted in the generation of anti-OprF antibodies at comparable levels to those induced following immunization with AdOprF, but immunization with AdOprF.RGD.Epi8 was associated with increased CD4 and CD8 gamma interferon T-cell responses against OprF as well as increased survival against lethal pulmonary challenge with agar-encapsulated P. aeruginosa. Importantly, repeat administration of AdOprF.RGD.Epi8 resulted in boosting of the humoral anti-OprF response as well as increased protection, whereas no boosting could be achieved with repeat administration of AdOprF. This suggests that the capsid-modified AdOprF.RGD.Epi8 vector is a more effective immunogen compared to a comparable wild-type Ad capsid, making it a good candidate for an anti-P. aeruginosa vaccine.
Worgall
Stefan
S
Department of Genetic Medicine, Weill Medical College of Cornell University, New York, New York 10021, USA. geneticmedicine@med.cornell.edu
Krause
Anja
A
Qiu
JianPing
J
Joh
Ju
J
Hackett
Neil R
NR
Crystal
Ronald G
RG
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002213:Capsid; D036022:Capsid Proteins / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D005260:Female; D005822:Genetic Vectors; D007114:Immunization; D051379:Mice; D008810:Mice, Inbred C57BL; D018272:Porins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D011552:Pseudomonas Infections / Q000276:immunology / Q000517:prevention & control; D011550:Pseudomonas aeruginosa / Q000276:immunology*
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D036022:Capsid Proteins; D018272:Porins