Course of serum levels of human IgG in SCID mice after (A) intravenous or (B) subcutaneous inoculation of ARH-77 cells. The treatment (100 μg/dose, total of 10 injections, once a week) was started 15 days after tumor inoculation. Data represent serum human IgG of each mouse treated with either control IgG (○, □, ⋄, ▵, ▿) or anti-HM1.24 MoAb (•, ▪, ♦, ▴, ▾).