Although the role of CD8 + T cells-derived IFN-γ has been clarified, little is known about the involvement of cytotoxic CD8 + T cells in cutaneous leishmaniasis. In a low-dose model of L. major infection, CD8 + T cell responses were shown not only to be protective, but also to mediate pathology (Belkaid et al., 2002) . Hence, it is possible that CTLs may be involved in the ulceration of skin lesions through tissue disruption. This suggests that perhaps two types of CD8 + T cell effectors are generated during L. major infection: antigen-specific CD8 + T cells that produce IFN-γ but lack cytotoxic activity; and CTLs that are potent killers but produce little to no IFN-γ and promote pathology.