Generation of a Nebulizable CDR-Modified MERS-CoV Neutralizing Human Antibody

Generation of a Nebulizable CDR-Modified MERS-CoV Neutralizing Human Antibody

Sang-il Kim, Sujeong Kim, Jin-Hee Kim, Soyoung Chang, Jung Min Shim, Jongwha Jin, Chungsu Lim, Songyi Baek, Ji-Young MIN, Wan Beom Park, Myoung-don Oh, Seungtaek Kim, Junho Chung

Middle East respiratory syndrome coronavirus (MERS-CoV) induces severe aggravating respiratory failure in infected patients, frequently resulting in mechanical ventilation. As limited therapeutic antibody is accumulated in lung tissue following systemic administration, inhalation is newly recognized as an alternative, possibly better, route of therapeutic antibody for pulmonary diseases. The nebulization process, however, generates diverse physiological stresses, and thus, the therapeutic antibody must be resistant to these stresses, remain stable, and form minimal aggregates. We first isolated a MERS-CoV neutralizing antibody that is reactive to the receptor-binding domain (RBD) of spike (S) glycoprotein. To increase stability, we introduced mutations into the complementarity-determining regions (CDRs) of the antibody. In the HCDRs (excluding HCDR3) in this clone, two hydrophobic residues were replaced with Glu, two residues were replaced with Asp, and four residues were replaced with positively charged amino acids. In LCDRs, only two Leu residues were replaced with Val. These modifications successfully generated a clone with significantly greater stability and equivalent reactivity and neutralizing activity following nebulization compared to the original clone. In summary, we generated a MERS-CoV neutralizing human antibody that is reactive to recombinant MERS-CoV S RBD protein for delivery via a pulmonary route by introducing stabilizing mutations into five CDRs.

2019

MERS-CoV, Aerosol delivery, Nebulizer, neutralizing antibody, antibody engineering, Pulmonary disease, complementarity determining regions

DOI: 10.3390/ijms20205073

International Journal of Molecular Sciences

MDPI AG

Biology (General), Chemistry

EN