IAI FigSearch
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Test, S. T.
Right arrow Articles by Lucas, A. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Test, S. T.
Right arrow Articles by Lucas, A. H.

 Previous Article  |  Next Article 

Infection and Immunity, May 2001, p. 3031-3040, Vol. 69, No. 5
0019-9567/01/$04.00+0   DOI: 10.1128/IAI.69.5.3031-3040.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Increased Immunogenicity and Induction of Class Switching by Conjugation of Complement C3d to Pneumococcal Serotype 14 Capsular Polysaccharide

Samuel T. Test,* Joyce Mitsuyoshi, Charles C. Connolly, and Alexander H. Lucas

Children's Hospital Oakland Research Institute, Oakland, California 94609-1673

Received 24 August 2000/Returned for modification 11 October 2000/Accepted 20 February 2001

Previous studies have demonstrated an adjuvant effect for the C3d fragment of complement C3 when coupled to T-dependent protein antigens. In this study, we examined the antibody response to covalent conjugates of C3d and a T-independent antigen, the capsular polysaccharide of serotype 14 Streptococcus pneumoniae (PPS14). We prepared a conjugate of mouse C3d and PPS14 and compared its immunogenicity with that of a conjugate of PPS14 and ovalbumin (OVA). When BALB/c mice were immunized with PPS14-C3d, there was a significant increase in serum anti-PPS14 concentrations compared with either native PPS14 or control PPS14-glycine conjugates. This was accompanied by a switch in anti-PPS14 from predominantly immunoglobulin M (IgM) to IgG1 by day 25 following primary immunization. Following secondary immunization with PPS14-C3d, there was a marked booster response and a further increase in the ratio of IgG1 to IgM anti-PPS14. Although the primary antibody response to the PPS14-OVA conjugate exceeded that induced by immunization with PPS14-C3d, serum anti-PPS14 concentrations after a second injection of PPS14-C3d were nearly identical to those induced by secondary immunization with PPS14-OVA. Experiments with athymic nude mice suggested that T cells were not required for the adjuvant effect of C3d on the primary immune response to PPS14 but were necessary for enhancement of the memory response after a second injection of PPS14-C3d. These studies show that the adjuvant effects of C3d extend to T-independent antigens as well as T-dependent antigens. As a means of harnessing the adjuvant potential of the innate immune system, C3d conjugates may prove useful as a component of vaccines against encapsulated bacteria.

* Corresponding author. Mailing address: Children's Hospital Oakland Research Institute, 5700 Martin Luther King, Jr. Way, Oakland, CA 94609-1673. Phone: (510) 450-7630. Fax: (510) 450-7910. E-mail: stest{at}chori.org.

Infection and Immunity, May 2001, p. 3031-3040, Vol. 69, No. 5
0019-9567/01/$04.00+0   DOI: 10.1128/IAI.69.5.3031-3040.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 2001 by the American Society for Microbiology. All rights reserved.