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Protective immunization in mice against group B streptococci using encapsulated C5a peptidase
American Journal of Obstetrics and Gynecology
  • Donna A Santillan, University of Iowa
  • M. E. Andracki
  • S. K. Hunter
Document Type
Peer Reviewed
Publication Date
NLM Title Abbreviation
Am J Obstet Gynecol
PubMed ID
DOI of Published Version
OBJECTIVE: The purpose of the study was to test whether C5a peptidase encapsulated within a biodegradable polymer can act as a vaccine and elicit an immune response to prevent group B streptococci (GBS) infection in mice and provide protection to pups. STUDY DESIGN: C5a peptidase was encapsulated in semipermeable microspheres of poly(lactide-co-glycolide). Female ICR mice were immunized with encapsulated C5a peptidase, free C5a peptidase, or empty microparticles. Booster doses were given at days 21 and 42. Antibody responses were measured by enzyme-linked immunosorbent assay. Challenge with GBS type III was performed 4 days after the final booster in the vaginal vault of adult mice and intraperitoneally 48 hours after the birth for pups. RESULTS: Encapsulated C5a peptidase elicited a systemic immunoglobulin (Ig) G antibody response after intramuscular and intranasal administration. Unencapsulated C5a peptidase elicited a smaller systemic response. In addition to the strong IgG response, a secretory IgA response was observed in the vaginal mucosa after intranasal vaccination. No evidence of GBS colonization was found in vaccinated mice. Eighty-seven percent and 81% of the pups from intramuscularly and intranasally vaccinated dams survived a 90% lethal dose (LD90) GBS challenge vs 9% born to nonvaccinated dams. CONCLUSION: Encapsulated C5a peptidase elicited significant immune responses and protection against GBS challenge. C5a peptidase microsphere encapsulation has potential as a GBS vaccine.
  • Adhesins,
  • Bacterial/pharmacology,
  • Animals,
  • Animals,
  • Newborn,
  • Disease Models,
  • Animal,
  • Endopeptidases/pharmacology,
  • Enzyme-Linked Immunosorbent Assay,
  • Female,
  • Immunity,
  • Mucosal,
  • Immunization/methods,
  • Mice,
  • Mice,
  • Inbred ICR,
  • Microspheres,
  • Pregnancy,
  • Pregnancy,
  • Animal,
  • Probability,
  • Sensitivity and Specificity,
  • Streptococcal Infections/immunology/prevention & control,
  • Streptococcal Vaccines/pharmacology,
  • Streptococcus agalactiae/immunology
Published Article/Book Citation
American Journal of Obstetrics and Gynecology, 198:1 (2008) pp.114.e1-114.e6.
Citation Information
Donna A Santillan, M. E. Andracki and S. K. Hunter. "Protective immunization in mice against group B streptococci using encapsulated C5a peptidase" American Journal of Obstetrics and Gynecology Vol. 198 Iss. 1 (2008) p. 114.e1 - 114.e6 ISSN: 1097-6868
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