FIG 2.

Monoclonal antibody 53C10 recognizes a conformational epitope on the HA molecule. The recognition of baculovirus-expressed CA/04 HA by antibody 53C10 (A) and antibody 63C7 (B) were evaluated by Western blotting (WB) as described in Materials and Methods. Below each lane is the amount of HA loaded. Molecular sizes are labeled on the left. Prior to WB, HA was denatured at 95°C for 10 min. (C) The binding of HA to 53C10 and 63C7 was determined in flow cytometry. MDCK cells were infected with CA/04. At 24 h postinfection, MDCK cells were evenly split into four tubes which were stained individually using either no antibody control, the antibody targeting NP protein (NP-Ab FR-667), 53C10 antibody, or 63C7 antibody. The percentage of cells bound by each antibody is shown.