Figure 3.

2F8 enhances humoral immunity to (a) H3N2 haemagglutinin (HA) and (b) H5N1 HA. Antibody dosing and immunization schedules are indicated above the graph; 0·4 mg 2F8 was used in these studies. HA mixed with alum or incomplete Freund’s adjuvant (IFA) is included for comparison. Levels of anti-HA antibodies were determined by enzyme-linked immunosorbent assay, as described in the Materials and methods section. Results represent at least two independent experiments with three to five mice per group. In (a), 2F8 is compared against both antigen-only and isotype control groups. **P < 0·01, *P < 0·05.