Abstract
Complement component C3 covalently attaches to Ags following activation, where the C3d cleavage fragment can function as a molecular adjuvant to augment humoral immune responses. C3d is proposed to exert its adjuvant-like activities by targeting Ags to the C3d receptor (CD21/35) expressed by B cells and follicular dendritic cells. To directly assess the importance of CD21/35 in mediating the immunostimulatory effects of C3d, CD21/35-deficient (CD21/35 -/-) mice were immunized with streptavidin (SA), SA-C3dg tetramers, recombinant HIV gp120 (gp120), or gp120 fused with linear multimers of C3d. Remarkably, SA and gp 120-specific Ab responses were significantly augmented in CD21/35-/- mice when these Ags were complexed with C3d in comparison to Ag alone. In fact, primary and secondary Ab responses and Ab-forming cell responses of CD21/35-/- mice approached those of wild-type mice immunized with SA-C3dg and gp120-C3d. Thus, C3d can function as a molecular adjuvant in the absence of CD21/35 expression.
Original language | English (US) |
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Pages (from-to) | 5833-5837 |
Number of pages | 5 |
Journal | Journal of Immunology |
Volume | 172 |
Issue number | 10 |
DOIs | |
State | Published - May 15 2004 |
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology