Figure 6.

IgG responses in mice to PEGylated LMB-2s. Mice in groups of five were injected i.p. with LMB-2 (○), cys1-LMB-2 (●), PEG5k-LMB-2 (□, ▪), and PEG20k-LMB-2 (▵, ▴) at a dose of 4 μg/mouse (○, ●, □, ▵) or 40 μg/mouse (▪, ▴) in PBS containing 0.2% mouse serum albumin. Two weeks after the first immunization, mice were once again immunized with the appropriate antigen. The specific IgG levels were determined by ELISA on day 21. The following symbols were used: ⋄, no treatment; ♦, 0.2% MSA/PBS.