Human Immunoglobulin Repertoire-Guided Immunogen Design Targeting HIV V2-Apex Broadly Neutralizing Antibody Precursors

ABSTRACT: Broadly neutralizing antibodies (bnAbs) to the HIV envelope (Env) V2-apex region are important leads for HIV vaccine design. Most V2-apex bnAbs engage Env with an uncommonly long heavy chain complementarity-determining region 3 (HCDR3), suggesting that rarity of bnAb precursors poses a challenge for vaccine priming. We created precursor sequence definitions for V2-apex HCDR3-dependent bnAbs and searched for related precursors in human antibody heavy chain ultradeep sequencing data from 14 HIV-unexposed donors. We found potential precursors in a majority of donors for only two long-HCDR3 V2-apex bnAbs, PCT64 and PG9, identifying these bnAbs as priority vaccine targets. We then engineered ApexGT Env trimers that bind inferred germlines for PCT64 and PG9 and have higher affinities for bnAbs; determined cryo-EM structures of ApexGT trimers bound to inferred germline and bnAb forms of PCT64 and PG9; and developed an mRNA-encoded cell-surface trimer for our lead ApexGT candidate. The methods and immunogens developed here have promise to assist the development of an HIV vaccine.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human) Human Immunodeficiency Virus

TISSUE(S): Epithelial Cell

SUBMITTER: Sabyasachi Baboo  

LAB HEAD: John R. Yates III

PROVIDER: PXD033766 | Pride | 2023-03-11

REPOSITORIES: Pride