Development and structural characterization of a two-MAb cocktail for delayed treatment of enterovirus D68 infections

Abstract

Enterovirus D68 (EV-D68) is an emerging pathogen associated with respiratory diseases and/or acute flaccid myelitis. Here, two MAbs, 2H12 and 8F12, raised against EV-D68 virus-like particle (VLP), showed distinct preference in binding VLP and virion and in neutralizing different strains. The 2H12/8F12 cocktail exhibited balanced and potent neutralization effects and conferred broader protection in mice than single MAbs when given at onset of symptoms. Cryo-EM structures of EV-D68 virion complexed with 2H12 or 8F12 showed that both antibodies bind to south rim of the canyon and obscure the canyon, blocking virus–cell binding. Additionally, 2H12 binding could partially impair virions and trigger uncoating, resulting in premature viral RNA release. We also captured an uncoating intermediate induced by 2H12 binding, not detected before in picornaviruses. Our study elucidates neutralizing mechanisms of the MAbs and supports further development of the 2H12/8F12 cocktail as a broad-spectrum therapeutic agent against EV-D68 infections in humans.

Integrative overview of antibodies against SARS-CoV-2 and their possible applications in COVID-19 prophylaxis and treatment

“…Although it has been related to SARS-CoV-2 infectivity and worsened COVID-19 symptoms, its participation in virus resistance has scarcely been demonstrated [ 48 ]. In contrast, Abs such as 2H2, 3C1, CC6, CC12, and CC25 neutralize the D614G variant [ 16 , 48 , 210 , 211 ]. As well as STE90-C11 recognized with elevated affinity RBD mutations like V367F, N439K, G476S, V483A, E484K, G485R, F486V [ 212 ].…”

“…In particular 2H2, potently neutralize SARS-CoV-2 pseudovirus (IC 50 : 0.025 μg/mL) and authentic SARS-CoV-2 (IC 50 : 0.007 μg/mL). Interestingly, the human–mouse chimeric Abs c2H2 and the c2H2/c3C1 cocktail (with the same IC 50 of 0.054 μg/mL) could significantly reduce viral loads in Balb/c mice, showing therapeutic efficacy [ 210 ].…”

Rapid characterization of spike variants via mammalian cell surface display

“… (a) Spike domain map (top) 11 , and a distribution of all non-synonymous mutations (total = 866,373) found in GISAID (accessed on 24/Feb/2021) (bottom) The NTD harbors 46% of all mutations while making up 23% of the protein. (b) Spike trimer structure (PDB: 7DDN 66 ) with domains colored as in panel (a). An enlarged structure of the NTD (blue) with alanine scan positions (white) is shown on the right.…”

“…The data were reference-subtracted and analyzed by Octet Data Analysis software v11.1 using steady-state analysis. All structures (7DDN 66 , 7C2L 42 , and 7JZL 16 ) were downloaded from the RCSB-PDB as PDB files and imported into ChimeraX 1.1 for visualization and image creation.…”

Anti-Inflammation, Immunomodulation and Therapeutic Repair in Current Clinical Trials for the Management of COVID-19

“…Antibody cocktail approaches have shown substantial promise in recent in vitro and in vivo studies for preventing SARS-CoV-2 escape. 33 , 34 Of special notes, one double-blind and Phase I–III trial suggests that an antibody cocktail against SARS-CoV-2 is safe and effective in an individual patient whose immune response has not yet been initiated. 35 Currently, there are eleven ongoing trials (NCT04381936, NCT04425629, NCT04426695, NCT04452318, NCT04519437, NCT04617535, NCT04634409, NCT04666441, NCT04691180, NCT04700163 and NCT04770467) using the synergistic neutralizing antibody cocktails in COVID-19 patients.…”