IL10 and infection: IL-10 production by Th1 cells was also reported in animals infected with Toxoplasma gondii (Jankovic et al., 2002; Shaw et al., 2006) or with Leishmania major (Anderson et al., 2007) and shown to be required for regulation of the immune response in these infections (Anderson et al., 2007; Jankovic et al., 2007).