Journal: bioRxiv

Article Title: Molecular basis for protection and cross-protection by human antibodies targeting the parainfluenza virus hemagglutinin-neuraminidase protein

doi: 10.64898/2026.03.03.709347

Figure Lengend Snippet: Antibody binding to virally infected cells and associated complement-dependent cytotoxicity assay. (A) LLC-MK2 cells were infected with PIV3 and stained with PE-conjugated PIV3 HN-specific mAbs 5217-2 and 5217-9. The anti-F mAb PIA174 was used as a positive control and a mAb against Streptococcus pneumoniae , PhtD3, was used as a negative control. Both the HN-specific mAbs and anti-F mAbs showed binding to PIV3-infected cells. The data represents three technical replicates from one experiment and are representative of two biological replicates. (B) NeutrAvidin beads were coated with biotinylated PIV3 HN protein and incubated with individual mAbs. Guinea pig complement C3 was then added to the immune complexes. Complement deposition was analyzed using the Cytek Aurora flow cytometer and measured relative to C3 deposition in the absence of antibody. Data points are the average of two technical replicates from one experiment and are representative of two biological replicates. The data is presented using mean values +/- standard deviation.

Article Snippet: Fluorescein-conjugated goat anti-guinea pig complement c3 (MP Biomedicals, Cat: 55385) was diluted 1:100 in PBS and incubated for 15 min in the dark.

Techniques: Binding Assay, Infection, CDC Assay, Staining, Positive Control, Negative Control, Incubation, Flow Cytometry, Standard Deviation