Cross-protective immunity of mice induced by oral immunization with pneumococcal surface adhesin a encapsulated in microspheres.
The global use of a capsular polysaccharide-based pneumococcal vaccine has been limited because of serotype-specific protection and poor effectiveness in individuals with low immunocompetency. The mucosal immune system develops earlier in infants and lasts longer in the elderly than does the systemic immune system. Furthermore, mucosal immunization is beneficial for AIDS patients, because human immunodeficiency virus-infected subjects can develop normal mucosal antibody responses even in late clinical phases. For these reasons, we evaluated recombinant pneumococcal surface adhesin A (rPsaA) of Streptococcus pneumoniae in terms of cross-protective immune responses after oral delivery. Encapsulated rPsaA provided higher immunogenicity than naked rPsaA. Coencapsulation or codelivery of the cholera toxin (CT) B subunit (CTB) and CT also increased the immunogenicity of rPsaA. Cross-protective immunities against five strains of S. pneumoniae (types 4, 6B, 14, 19F, and 23F) were induced after oral immunization with microencapsulated rPsaA. Lung colonization and septicemia caused by the five serotypes were significantly inhibited by oral immunization with microencapsulated rPsaA. These results suggest that rPsaA coencapsulated with CTB can be used as an oral vaccine to induce cross-protective immunity for the prevention of pneumococcal infection.
Seo
Jun-Young
JY
Biomedical Research Center, Korea Institute of Science and Technology, Seoul 136-791, Korea.
Seong
Seung Yong
SY
Ahn
Byung-Yoon
BY
Kwon
Ick Chan
IC
Chung
Hesson
H
Jeong
Seo Young
SY
D018829:Adhesins, Bacterial / Q000235:genetics / Q000627:therapeutic use*; D000284:Administration, Oral; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000918:Antibody Specificity; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000235:genetics / Q000627:therapeutic use*; D003429:Cross Reactions; D004339:Drug Compounding; D005260:Female; D008074:Lipoproteins / Q000235:genetics / Q000627:therapeutic use*; D026901:Membrane Transport Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D022242:Pneumococcal Vaccines / Q000235:genetics / Q000627:therapeutic use*; D011018:Pneumonia, Pneumococcal / Q000517:prevention & control*; D011994:Recombinant Proteins / Q000627:therapeutic use; D014611:Vaccination / Q000379:methods*; D014614:Vaccines, Synthetic / Q000627:therapeutic use
D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D002352:Carrier Proteins; D008074:Lipoproteins; D026901:Membrane Transport Proteins; D022242:Pneumococcal Vaccines; C085000:PsaA protein, Streptococcus; D011994:Recombinant Proteins; D014614:Vaccines, Synthetic