CD4 and neoplasm: Recent work by Kuhn et al. demonstrated that antitumor CD4+ T cell responses, including proliferation, tumor infiltration and intratumoral IFN-γ and TNF production, can be promoted by administration of monosodium urate acid crystals in combination with Mycobacterium smegmatis and this response completely depends on IL-1R signaling in the host (167, 168).