Project 1, entitled Immunogen Design and Selection, plays the major role of generating the HIV envelope glycoprotein-based candidate vaccine immunogens to be analyzed in this HIVRAD.
In Aim 1, we will design novel trimeric immunogens based upon three distinct strategies. Initially, we will utilize recent mapping data performed in our collaborative group on CD4 binding-site (CD4bs) directed neutralizing antibodies (nAbs) isolated from non-human primates (NHPs) immunized with HIV Env trimeric immunogens. We compared the NHP CD4bs nAbs to the known, more broadly nAbs isolated from HIV-1-infected human subjects t)y alanine scanning mutagenesis ofthe HlV-1 gpl 20. Using the alanine scan information, we generated divergent mAb footprint patterns between the NHP CD4bs Mabs and the structurally defined footprint ofthe human bNabs. Armed with this information, we will design stabilized trimers that preferentially present neutralizing epitopes to activate VH genes associated with the infection-elicited bNabs and to elicit neutralizing antibody responses by vaccination. In the 2nd approach, we will assess the ability of loop-deleted, conformationally stabilized trimers, which more rapidly elicit CD4bs-directed in rabbits, to do so in NHPs. Improved versions will be assessed for their capacity to elicit CD4bs Mabs or to synergize with full-length trimers to elicit CD4bs-directed B cell responses.
In Aim 2, we will generate sFVs of our isolated NHP CD4bs Abs (GE148 or GE136) and perform yeast cell-surface display, random mutagenesis and selection with conformationally stabilized Env core antigens to determine if we can evolve these non-broadly neutralizing CD4bs mAbs to become more broadly neutralizing and the levels of mutation required to achieve such a capacity. Finally, in Aim 3, we will select novel Env trimeric immunogens using directed evolution as a complementary approach to rational Env design. Env trimers, stabilized in the context of infectious virus using selection criteria established by Dr. Michael Zwick, will be assessed for their ability to elicit B cell responses in NHPs. In addition, HIV-1 Env trimers will be selected in the Zwick laboratory for recognition by NHP germline equivalents of CD4bs bNabs (e.g. VH1-02) or PG9 or PGT128 by iterative affinity-selection of viral mutants.

Public Health Relevance

The major objective of Project 1 is to generate novel HIV Env immunogens, an undertaking which is essential forthe overall goal ofthe HIVRAD to elicit broadly neutralizing antibodies to the human pathogen HIV-1. The successful elicitation of such antibodies would be a large step forward toward the goal of generating a broadly effective HlV-1 vaccine and would have a substantial impact on improving human public health.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program Projects (P01)
Project #
5P01AI104722-04
Application #
9235216
Study Section
Special Emphasis Panel (ZAI1)
Project Start
Project End
Budget Start
2017-04-01
Budget End
2018-03-31
Support Year
4
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Scripps Research Institute
Department
Type
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Khan, Salar N; Sok, Devin; Tran, Karen et al. (2018) Targeting the HIV-1 Spike and Coreceptor with Bi- and Trispecific Antibodies for Single-Component Broad Inhibition of Entry. J Virol 92:
Sarkar, Anita; Bale, Shridhar; Behrens, Anna-Janina et al. (2018) Structure of a cleavage-independent HIV Env recapitulates the glycoprotein architecture of the native cleaved trimer. Nat Commun 9:1956
Yang, Lifei; Sharma, Shailendra Kumar; Cottrell, Christopher et al. (2018) Structure-Guided Redesign Improves NFL HIV Env Trimer Integrity and Identifies an Inter-Protomer Disulfide Permitting Post-Expression Cleavage. Front Immunol 9:1631
Bale, Shridhar; Martiné, Alexandra; Wilson, Richard et al. (2018) Cleavage-Independent HIV-1 Trimers From CHO Cell Lines Elicit Robust Autologous Tier 2 Neutralizing Antibodies. Front Immunol 9:1116
Singh, Rajendra; Stoneham, Charlotte; Lim, Christopher et al. (2018) Phosphoserine acidic cluster motifs bind distinct basic regions on the ? subunits of clathrin adaptor protein complexes. J Biol Chem 293:15678-15690
Cale, Evan M; Gorman, Jason; Radakovich, Nathan A et al. (2017) Virus-like Particles Identify an HIV V1V2 Apex-Binding Neutralizing Antibody that Lacks a Protruding Loop. Immunity 46:777-791.e10
Karlsson Hedestam, Gunilla B; Guenaga, Javier; Corcoran, Martin et al. (2017) Evolution of B cell analysis and Env trimer redesign. Immunol Rev 275:183-202
Dubrovskaya, Viktoriya; Guenaga, Javier; de Val, Natalia et al. (2017) Targeted N-glycan deletion at the receptor-binding site retains HIV Env NFL trimer integrity and accelerates the elicited antibody response. PLoS Pathog 13:e1006614
Voss, James E; Andrabi, Raiees; McCoy, Laura E et al. (2017) Elicitation of Neutralizing Antibodies Targeting the V2 Apex of the HIV Envelope Trimer in a Wild-Type Animal Model. Cell Rep 21:222-235
Kwong, Peter D; Chuang, Gwo-Yu; DeKosky, Brandon J et al. (2017) Antibodyomics: bioinformatics technologies for understanding B-cell immunity to HIV-1. Immunol Rev 275:108-128

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