Induction of HIV-1 broad neutralizing antibodies in 2F5 knock-in mice: selection against membrane proximal external region-associated autoreactivity limits T-dependent responses.

Published

Journal Article

A goal of HIV-1 vaccine development is to elicit broadly neutralizing Abs (BnAbs). Using a knock-in (KI) model of 2F5, a human HIV-1 gp41 membrane proximal external region (MPER)-specific BnAb, we previously demonstrated that a key obstacle to BnAb induction is clonal deletion of BnAb-expressing B cells. In this study of this model, we provide a proof-of-principle that robust serum neutralizing IgG responses can be induced from pre-existing, residual, self-reactive BnAb-expressing B cells in vivo using a structurally compatible gp41 MPER immunogen. Furthermore, in CD40L-deficient 2F5 KI mice, we demonstrate that these BnAb responses are elicited via a type II T-independent pathway, coinciding with expansion and activation of transitional splenic B cells specific for 2F5's nominal gp41 MPER-binding epitope (containing the 2F5 neutralization domain ELDKWA). In contrast, constitutive production of nonneutralizing serum IgGs in 2F5 KI mice is T dependent and originates from a subset of splenic mature B2 cells that have lost their ability to bind 2F5's gp41 MPER epitope. These results suggest that residual, mature B cells expressing autoreactive BnAbs, like 2F5 as BCR, may be limited in their ability to participate in T-dependent responses by purifying selection that selectively eliminates reactivity for neutralization epitope-containing/mimicked host Ags.

Full Text

Duke Authors

Cited Authors

  • Verkoczy, L; Chen, Y; Zhang, J; Bouton-Verville, H; Newman, A; Lockwood, B; Scearce, RM; Montefiori, DC; Dennison, SM; Xia, S-M; Hwang, K-K; Liao, H-X; Alam, SM; Haynes, BF

Published Date

  • September 1, 2013

Published In

Volume / Issue

  • 191 / 5

Start / End Page

  • 2538 - 2550

PubMed ID

  • 23918977

Pubmed Central ID

  • 23918977

Electronic International Standard Serial Number (EISSN)

  • 1550-6606

Digital Object Identifier (DOI)

  • 10.4049/jimmunol.1300971

Language

  • eng

Conference Location

  • United States