Previous Article | Next Article ![]()
Infection and Immunity, September 1999, p. 4862-4869, Vol. 67, No. 9
Department of
Pediatrics1 and Institute of
Pathology,
Received 31 March 1999/Returned for modification 12 May
1999/Accepted 2 July 1999
Conjugation of various serotypes of pneumococcal polysaccharide
(PnPS) to carrier protein enhances the magnitude of the
polysaccharide-specific antibody response, presumably by eliciting
T-cell help. However, variability in PnPS serotype-specific
immunogenicity has been observed. CBA/J mice immunized with either 6B
or 19F PnPS conjugated to the protein carrier Cross Reactive
Material197 (CRM197) produce a strong anti-PnPS
antibody response; however, when mice are immunized with 23F PnPS
conjugated to CRM197, they fail to produce a significant anti-PnPS response. In order to determine whether this difference was
related to alterations in antigen processing of the carrier protein and
the subsequent T-cell responses, we studied proliferation of
lymphocytes from CBA/J mice immunized with CRM197 alone or conjugated to 6B, 19F, or 23F PnPS. T-cell proliferative responses to
synthetic peptides demonstrated that lymph node cells elicited by the
poorly immunogenic conjugate 23F-CRM197 recognized many, but not all, of the epitopes recognized by lymph node cells elicited by
6B- and 19F-CRM197 as well as additional epitopes. Despite marked differences in PnPS-specific immunogenicity, all mice made high titers of CRM197 antibodies of the immunoglobulin
G1 isotype. Cells from mice immunized with any of the
conjugates yielded vigorous T-cell responses to whole antigen. We
conclude that the serotype of PnPS can alter the peptide specificities
of T-cell responses, but even a poorly immunogenic PnPS conjugate can
elicit a significant T-cell response. Thus, conjugation of PnPS to a
carrier protein that elicits carrier-specific T- and B-cell responses
does not necessarily enhance PnPS immunogenicity.
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
B- and T-Cell Immune Responses to Pneumococcal Conjugate
Vaccines: Divergence between Carrier- and
Polysaccharide-Specific Immunogenicity
*
Corresponding author. Mailing address for John R. Schreiber: Division of Infectious Diseases, Rainbow Babies and
Children's Hospital, 11100 Euclid Ave., Cleveland, OH 44106. Phone:
(216) 844-3645. Fax: (216) 844-8362. E-mail:
jrs3{at}po.cwru.edu. Mailing address for Neil S. Greenspan:
Institute of Pathology, Biomedical Research Building, Rm. 927, Case
Western Reserve University School of Medicine, 10900 Euclid Ave.,
Cleveland, OH 44106. Phone: (216) 368-1280. Fax: (216) 368-1300. E-mail: nsg{at}po.cwru.edu.
Infection and Immunity, September 1999, p. 4862-4869, Vol. 67, No. 9
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»