Download MendeleyPseudomonas aeruginosa PcrV and Psl, the Molecular Targets of Bispecific Antibody MEDI3902, Are Conserved Among Diverse Global Clinical Isolates.
Tabor, D.E., Oganesyan, V., Keller, A.E., Yu, L., McLaughlin, R.E., Song, E., Warrener, P., Rosenthal, K., Esser, M., Qi, Y., Ruzin, A., Stover, C.K., DiGiandomenico, A.(2018) J Infect Dis 218: 1983-1994
- PubMed: 30016475
- DOI: https://doi.org/10.1093/infdis/jiy438
- Primary Citation of Related Structures:
6CYF - PubMed Abstract:
Bispecific antibody MEDI3902, targeting the Pseudomonas aeruginosa type 3 secretion system (PcrV) and Psl exopolysaccharide, is currently in phase 2b development for prevention of nosocomial pneumonia in patients undergoing mechanical ventilation. We surveyed a diverse collection of isolates to study MEDI3902 epitope conservation and protective activity. P. aeruginosa clinical isolates (n = 913) were collected from diverse patients and geographic locations during 2003-2014. We conducted whole-genome sequencing; performed PcrV and Psl expression analyses via immunoblotting and enzyme-linked immunosorbent assay, respectively; performed crystallography to determine the MEDI3902 PcrV epitope, using anti-PcrV Fab and PcrV components (resolved at 2.8 Å); and evaluated MEDI3902 protective activity against select isolates in vitro and in vivo. Intact psl operon and pcrV genes were present in 94% and 99% of isolates, respectively, and 99.9% of isolates contained at least one of the genetic elements. Anti-Psl binding was confirmed in tested isolates harboring a complete Psl operon or lacking nonessential psl genes. We identified 46 PcrV variant sequences, and MEDI3902-PcrV contact residues were preserved. MEDI3902 maintained potent in vivo activity against various strains, including strains expressing only a single target. Psl and PcrV are highly prevalent in global clinical isolates, suggesting MEDI3902 can mediate broad coverage against P. aeruginosa.
Organizational Affiliation:
Translational Medicine, Gaithersburg, Maryland.
