Potent NK Cell-Mediated Elimination of HIV-1-Infected Cells Mobilized by a gp120-Bispecific and Hexavalent Broadly Neutralizing Fusion Protein.

TitlePotent NK Cell-Mediated Elimination of HIV-1-Infected Cells Mobilized by a gp120-Bispecific and Hexavalent Broadly Neutralizing Fusion Protein.
Publication TypeJournal Article
Year of Publication2017
AuthorsBardhi A, Wu Y, Chen W, Li W, Zhu Z, Zheng JHua, Wong H, Jeng E, Jones J, Ochsenbauer C, Kappes JC, Dimitrov DS, Ying T, Goldstein H
JournalJ Virol
Volume91
Issue20
Date Published2017 10 15
ISSN1098-5514
KeywordsAnimals, Antibodies, Bispecific, Antibodies, Neutralizing, Antibody-Dependent Cell Cytotoxicity, CD4 Antigens, Disease Models, Animal, HIV Envelope Protein gp120, HIV Infections, HIV-1, Killer Cells, Natural, Leukocytes, Mononuclear, Macaca mulatta, Mice, Recombinant Proteins, Simian Acquired Immunodeficiency Syndrome, Simian Immunodeficiency Virus, Virus Latency
Abstract

Antibodies bound to human immunodeficiency virus type 1 (HIV-1) envelope protein expressed by infected cells mobilize antibody-dependent cellular cytotoxicity (ADCC) to eliminate the HIV-1-infected cells and thereby suppress HIV-1 infection and delay disease progression. Studies treating HIV-1-infected individuals with latency reactivation agents to reduce their latent HIV-1 reservoirs indicated that their HIV-1-specific immune responses were insufficient to effectively eliminate the reactivated latent HIV-1-infected T cells. Mobilization of ADCC may facilitate elimination of reactivated latent HIV-1-infected cells to deplete the HIV-1 reservoir and contribute to a functional HIV-1 cure. The most effective antibodies for controlling and eradicating HIV-1 infection would likely have the dual capacities of potently neutralizing a broad range of HIV-1 isolates and effectively mobilizing HIV-1-specific ADCC to eliminate HIV-1-infected cells. For this purpose, we constructed LSEVh-LS-F, a broadly neutralizing, defucosylated hexavalent fusion protein specific for both the CD4 and coreceptor gp120-binding sites. LSEVh-LS-F potently inhibited HIV-1 and simian-human immunodeficiency virus (SHIV) infection in humanized mouse and macaque models, respectively, including neutralization of HIV-1 strains resistant to the broadly neutralizing antibodies VRC01 and 3BNC117. We developed a novel humanized mouse model to evaluate human NK cell-mediated elimination of HIV-1-infected cells by ADCC and utilized it to demonstrate that LSEVh-LS-F rapidly mobilized NK cells to eliminate >80% of HIV-1-infected cells 1 day after its administration. The capacity of LSEVh-LS-F to eliminate HIV-1-infected cells via ADCC combined with its broad neutralization activity supports its potential use as an immunotherapeutic agent to eliminate reactivated latent cells and deplete the HIV-1 reservoir. Mobilization of antibody-dependent cellular cytotoxicity (ADCC) to eliminate reactivated latent HIV-1-infected cells is a strategy which may contribute to depleting the HIV-1 reservoir and achieving a functional HIV-1 cure. To more effectively mobilize ADCC, we designed and constructed LSEVh-LS-F, a broadly neutralizing, defucosylated hexavalent fusion protein specific for both the CD4 and coreceptor gp120-binding sites. LSEVh-LS-F potently inhibited HIV-1 and SHIV infection in humanized mouse and macaque models, respectively, including neutralization of an HIV-1 strain resistant to the broadly neutralizing antibodies VRC01 and 3BNC117. Using a novel humanized mouse model, we demonstrated that LSEVh-LS-F rapidly mobilized NK cells to eliminate >80% of HIV-1-infected cells 1 day after its administration. The capacity of LSEVh-LS-F to eliminate HIV-1-infected cells via ADCC combined with its broad neutralization activity supports its potential use as an immunotherapeutic agent to eliminate reactivated latent cells and deplete the HIV-1 reservoir.

DOI10.1128/JVI.00937-17
Alternate JournalJ. Virol.
PubMed ID28794022
PubMed Central IDPMC5625480
Grant ListR01 DA033788 / DA / NIDA NIH HHS / United States
P30 AI124414 / AI / NIAID NIH HHS / United States
R01 DA036171 / DA / NIDA NIH HHS / United States
P30 CA013330 / CA / NCI NIH HHS / United States
UM1 AI126617 / AI / NIAID NIH HHS / United States