In vivo evolution of env in SHIV-AD8EO-infected rhesus macaques after AAV-vectored delivery of eCD4-Ig

Daniel O'Hagan; Siddhartha Shandilya; Lincoln J Hopkins; Patricia A Hahn; Sebastian P Fuchs; José M Martinez-Navio; Michael D Alpert; Mathew R Gardner; Ronald C Desrosiers; Guangping Gao; Jeffrey D Lifson; Michael Farzan; Amir Ardeshir; Mauricio A Martins

doi:10.1016/j.ymthe.2024.12.015

In vivo evolution of env in SHIV-AD8_EO-infected rhesus macaques after AAV-vectored delivery of eCD4-Ig

Mol Ther. 2024 Dec 12:S1525-0016(24)00814-1. doi: 10.1016/j.ymthe.2024.12.015. Online ahead of print.

Affiliations

¹ Department of Immunology and Microbiology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL 33458, USA.
² California National Primate Research Center, University of California, Davis, Davis, CA 95616, USA.
³ Department of Immunology and Microbiology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL 33458, USA; The Skaggs Graduate School, The Scripps Research Institute, Jupiter, FL 33458, USA.
⁴ University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
⁵ Emmune Inc., Juno Beach, FL 33408, USA.
⁶ Department of Medicine, Emory University, Atlanta, GA 30322, USA.
⁷ Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605, USA.
⁸ AIDS and Cancer Virus Program, Frederick National Laboratory, Frederick, MD 21702, USA.
⁹ Boston Children's Hospital, Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
¹⁰ Tulane National Primate Research Center, Tulane University, Covington, LA 70433, USA.
¹¹ Department of Immunology and Microbiology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL 33458, USA. Electronic address: mauricio.martins@ufl.edu.

PMID: 39673132
DOI: 10.1016/j.ymthe.2024.12.015

Abstract

eCD4-immunoglobulin (Ig) is an HIV entry inhibitor that mimics the engagement of both CD4 and CCR5 with the HIV envelope (Env) protein, a property that imbues it with remarkable potency and breadth. However, env is exceptionally genetically malleable and can evolve to escape a wide variety of entry inhibitors. Here we document the evolution of partial eCD4-Ig resistance in SHIV-AD8_EO-infected rhesus macaques (RMs) treated with adeno-associated virus vectors encoding eCD4-Ig. In one RM, setpoint viremia plateaued at 1,000 vRNA copies/mL, despite concomitant serum concentrations of eCD4-Ig in the 60-110 μg/mL range, implying that the virus had gained partial eCD4-Ig resistance. Env mutations occurring prominently in this animal were cloned and further characterized. Three of these mutations (R315G, A436T, and G471E) were sufficient to confer substantial resistance to eCD4-Ig-mediated neutralization onto the parental Env, accompanied by a marked loss of viral fitness. This resistance was not driven by decreased CD4 affinity, subverted sulfopeptide mimicry, changes to co-receptor tropism, or by a gain of CD4 independence. Rather, our data argue that the Env evolving in this animal attained eCD4-Ig resistance by decreasing triggerability, stabilizing the triggered state, and changing the nature of its relationship to the host CD4.

Keywords: AAV; HIV; SHIV; SIV; eCD4-Ig; env; mutations; resistance; rhesus macaques; therapy.