Anti-HFRS Human IgG Produced in Transchromosomic Bovines Has Potent Hantavirus Neutralizing Activity and Is Protective in Animal Models.

Casey C Perley,Eddie Sullivan,Melanie V Cohen,Jay W Hooper,Steven A Kwilas,Jerel B Vega,Padmanabh Chivukula,Priya P Karmali,Hua Wu,Lucia M Principe,Rebecca L Brocato,Joshua Shamblin,Christoph Bausch,Brandon Somerville

doi:10.3389/fmicb.2020.00832

Abstract

We explored an emerging technology to produce anti-Hantaan virus (HTNV) and anti-Puumala virus (PUUV) neutralizing antibodies for use as pre- or post-exposure prophylactics. The technology involves hyperimmunization of transchomosomic bovines (TcB) engineered to express human polyclonal IgG antibodies with HTNV and PUUV DNA vaccines encoding GnGc glycoproteins. For the anti-HTNV product, TcB was hyperimmunized with HTNV DNA plus adjuvant or HTNV DNA formulated using lipid nanoparticles (LNP). The LNP-formulated vaccine yielded fivefold higher neutralizing antibody titers using 10-fold less DNA. Human IgG purified from the LNP-formulated animal (SAB-159), had anti-HTNV neutralizing antibody titers >100,000. SAB-159 was capable of neutralizing pseudovirions with monoclonal antibody escape mutations in Gn and Gc demonstrating neutralization escape resistance. SAB-159 protected hamsters from HTNV infection when administered pre- or post-exposure, and limited HTNV infection in a marmoset model. An LNP-formulated PUUV DNA vaccine generated purified anti-PUUV IgG, SAB-159P, with a neutralizing antibody titer >600,000. As little as 0.33 mg/kg of SAB-159P protected hamsters against PUUV infection for pre-exposure and 10 mg/kg SAB-159P protected PUUV-infected hamsters post-exposure. These data demonstrate that DNA vaccines combined with the TcB-based manufacturing platform can be used to rapidly produce potent, human, polyclonal, escape-resistant anti-HTNV, and anti-PUUV neutralizing antibodies that are protective in animal models.

Highlights

MATERIALS AND METHODSHantaan virus (HTNV) and Puumala virus (PUUV) are zoonotic viruses, causing a disease known as hemorrhagic fever with renal syndrome (HFRS) (Elliot et al, 2013)
More recently we found that lipid nanoparticles (LNP) formulation increased the efficiency of DNA vaccine immunogenicity in multiple species, including transchomosomic bovines (TcB)
We initially compared the response elicited by a HTNV M segment based DNA vaccine using either SAB-adj-1 adjuvant or LNP formulation

Summary

MATERIALS AND METHODS

Hantaan virus (HTNV) and Puumala virus (PUUV) are zoonotic viruses, causing a disease known as hemorrhagic fever with renal syndrome (HFRS) (Elliot et al, 2013). TcB have been used to produce polyclonal neutralizing antibody products against numerous viruses including Zika virus, Ebola virus (EBOV), Venezuelan Equine Encephalitis and Middle East respiratory syndrome coronavirus, and two hantaviruses that cause hantavirus pulmonary syndrome, Andes virus (ANDV) and Sin Nombre virus (SNV) (Hooper et al, 2014a; Bounds et al, 2015; Dye et al, 2016; Luke et al, 2016; Gardner et al, 2017; Stein et al, 2017) For all of these viruses, passive transfer of TcB-derived IgG immediately prior to or post challenge prevented disease, elicited partial protection, or rapidly reduced viral titer (Hooper et al, 2014a; Bounds et al, 2015; Dye et al, 2016; Luke et al, 2016; Stein et al, 2017; Rosenke et al, 2018). We demonstrate that it is possible to combine DNA vaccine technology with the TcB platform to produce potent human polyclonal IgG for use as a pre- or post-exposure prophylactic for HFRS caused by HTNV and PUUV infection. MAbs 3D5 and HCO2 were obtained from the Joel Dalrymple collection at BEI Resources

Animal Procedures

RESULTS

DISCUSSION

ETHICS STATEMENT