Figure 3.

Ab responses to KLH. (a) The hind footpads of GM-CSF −/− (•) and GM-CSF +/+ (○) mice were injected with 100 μg KLH in CFA. (b) The hind footpads of GM-CSF −/− mice were injected with 100 μg KLH with 40 ng rGM-CSF in CFA followed by 10 ng/day rGM-CSF injected i.p. for 5 days a week until mice were killed: GM-CSF −/− (•) and GM-CSF −/− with rGM-CSF (▵). Each group had four mice. Individual mice were bled at 1, 2, and 4 weeks after immunization and sera were titered for anti-KLH antibody at doubling dilutions of 1:500 to 1:16,000 using isotype-specific ELISA. The results of serum samples diluted 1:4,000 are plotted in this figure. Similar differences were seen with the other serum dilutions. Specificity of antibodies were confirmed using hen egg lysozyme as a negative control.