A recombinant human monoclonal antibody to human metapneumovirus fusion protein that neutralizes virus in vitro and is effective therapeutically in vivo.
Human metapneumovirus (hMPV) is a recently discovered paramyxovirus that is a major cause of lower-respiratory-tract disease. hMPV is associated with more severe disease in infants and persons with underlying medical conditions. Animal studies have shown that the hMPV fusion (F) protein alone is capable of inducing protective immunity. Here, we report the use of phage display technology to generate a fully human monoclonal antibody fragment (Fab) with biological activity against hMPV. Phage antibody libraries prepared from human donor tissues were selected against recombinant hMPV F protein with multiple rounds of panning. Recombinant Fabs then were expressed in bacteria, and supernatants were screened by enzyme-linked immunosorbent assay and immunofluorescent assays. A number of Fabs that bound to hMPV F were isolated, and several of these exhibited neutralizing activity in vitro. Fab DS7 neutralized the parent strain of hMPV with a 60% plaque reduction activity of 1.1 mug/ml and bound to hMPV F with an affinity of 9.8 x10(-10) M, as measured by surface plasmon resonance. To test the in vivo activity of Fab DS7, groups of cotton rats were infected with hMPV and given Fab intranasally 3 days after infection. Nasal turbinates and lungs were harvested on day 4 postinfection and virus titers determined. Animals treated with Fab DS7 exhibited a >1,500-fold reduction in viral titer in the lungs, with a modest 4-fold reduction in the nasal tissues. There was a dose-response relationship between the dose of DS7 and virus titer. Human Fab DS7 may have prophylactic or therapeutic potential against severe hMPV infection.
Williams
John V
JV
Pediatric Infectious Diseases, Vanderbilt University Medical Center, D-7235 Medical Center North, 1161 21st Avenue South, Nashville, TN 37232. john.williams@vanderbilt.edu
Chen
Zhifeng
Z
Cseke
Gabriella
G
Wright
David W
DW
Keefer
Christopher J
CJ
Tollefson
Sharon J
SJ
Hessell
Ann
A
Podsiad
Amy
A
Shepherd
Bryan E
BE
Sanna
Pietro Paolo
PP
Burton
Dennis R
DR
Crowe
James E
JE
Williamson
R Anthony
RA
D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D000939:Epitopes; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000235:genetics / Q000276:immunology*; D007223:Infant; D029121:Metapneumovirus / Q000235:genetics / Q000276:immunology*; D009500:Neutralization Tests; D018184:Paramyxoviridae Infections / Q000628:therapy*; D019151:Peptide Library; D051381:Rats; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology*; D016205:Sigmodontinae; D014760:Viral Fusion Proteins / Q000235:genetics / Q000276:immunology*; D019562:Viral Load
D000911:Antibodies, Monoclonal; D000939:Epitopes; D007140:Immunoglobulin Fab Fragments; D019151:Peptide Library; D011994:Recombinant Proteins; D014760:Viral Fusion Proteins