Figure 1.

Immunohistochemistry of C. parvum-injected livers of homozygous mutant (AIM^−/−) (B and D) and wild-type (AIM^+/+) mice (A and C) at 17 days after injection. A and B: Accumulations of F4/80⁺ macrophages and granuloma formation are more prominent in an AIM^−/− mouse (B) than in an AIM^+/+ mouse (A). Original magnification, ×100. C and D: Infiltration of Thy1.2⁺ T cells in the granulomas of an AIM^−/− mouse (D) is less remarkable than that of an AIM^+/+ mouse (C). Original magnification, ×200.