TY - JOUR
T1 - Binding and neutralizing capacity of respiratory syncytial virus (Rsv)-specific recombinant IgG against RSV in h uman milk, gastric and intestinal fluids from infants
AU - Demers-Mathieu, Veronique
AU - Lueangsakulthai, Jiraporn
AU - Qu, Yunyao
AU - Scottoline, Brian P.
AU - Dallas, David C.
N1 - Funding Information:
Funding: This research was funded by the Bill & Melinda Gates Foundation (OPP1183649).
Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/7
Y1 - 2020/7
N2 - Oral administration of pathogen-specific recombinant antibodies may help to prevent infant gastrointestinal (GI) pathogen infection; however, to neutralize an infectious agent, these antibodies must resist degradation in the GI tract. Palivizumab, a recombinant antibody specific for the respiratory syncytial virus (RSV), was used as a model for pathogen-specific IgG in human milk. The aim was to compare the remaining binding capacity of palivizumab in milk between three mothers after exposure to an in vitro model of infant gastrointestinal digestion (gastric and duodenal fluids) using ELISA. The neutralizing capacity of palivizumab in pooled human milk, gastric contents, and stools from preterm infants was also evaluated for blocking RSV with green fluorescent protein (RSV-GFP) infection in Hep-2 cells using confocal and inverted microscopy and flow cytometry. The reduction of palivizumab binding capacity in human milk and digested samples was slightly different between mothers. Overall, palivizumab decreased 50% after simulated gastric digestion with pepsin and 62% after simulated intestinal digestion with pancreatin. Palivizumab (2–8 µg/mL) in human milk or stool samples blocked RSV (3.4 × 104 FFU/mL) infection (no syncytia formation on Hep-2 cells) by microscopy. Syncytia formation was detected on Hep-2 cells when RSV was incubated in gastric contents or virus medium with 2–4 µg/mL of palivizumab, but no infection was observed at 8 µg/mL. No fluorescence (absence of infected cells) was detected when palivizumab (100 µg/mL) was incubated in human milk or medium with RSV-GFP (1.1 × 105 FFU/mL), whereas fluorescence increased with the reduced concentration of palivizumab using flow cytometry. These results suggest that undigested and digested matrices could change the binding and neutralizing capacity of viral pathogen-specific antibodies.
AB - Oral administration of pathogen-specific recombinant antibodies may help to prevent infant gastrointestinal (GI) pathogen infection; however, to neutralize an infectious agent, these antibodies must resist degradation in the GI tract. Palivizumab, a recombinant antibody specific for the respiratory syncytial virus (RSV), was used as a model for pathogen-specific IgG in human milk. The aim was to compare the remaining binding capacity of palivizumab in milk between three mothers after exposure to an in vitro model of infant gastrointestinal digestion (gastric and duodenal fluids) using ELISA. The neutralizing capacity of palivizumab in pooled human milk, gastric contents, and stools from preterm infants was also evaluated for blocking RSV with green fluorescent protein (RSV-GFP) infection in Hep-2 cells using confocal and inverted microscopy and flow cytometry. The reduction of palivizumab binding capacity in human milk and digested samples was slightly different between mothers. Overall, palivizumab decreased 50% after simulated gastric digestion with pepsin and 62% after simulated intestinal digestion with pancreatin. Palivizumab (2–8 µg/mL) in human milk or stool samples blocked RSV (3.4 × 104 FFU/mL) infection (no syncytia formation on Hep-2 cells) by microscopy. Syncytia formation was detected on Hep-2 cells when RSV was incubated in gastric contents or virus medium with 2–4 µg/mL of palivizumab, but no infection was observed at 8 µg/mL. No fluorescence (absence of infected cells) was detected when palivizumab (100 µg/mL) was incubated in human milk or medium with RSV-GFP (1.1 × 105 FFU/mL), whereas fluorescence increased with the reduced concentration of palivizumab using flow cytometry. These results suggest that undigested and digested matrices could change the binding and neutralizing capacity of viral pathogen-specific antibodies.
KW - Neonatal infection
KW - Passive immunity
KW - Pathogen-specific antibody
UR - http://www.scopus.com/inward/record.url?scp=85087403398&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85087403398&partnerID=8YFLogxK
U2 - 10.3390/nu12071904
DO - 10.3390/nu12071904
M3 - Article
C2 - 32605037
AN - SCOPUS:85087403398
VL - 12
SP - 1
EP - 16
JO - Nutrients
JF - Nutrients
SN - 2072-6643
IS - 7
M1 - 1904
ER -