CD4 and neoplasm: While CD4+ Th1 cells producing IFNγ are required to activate macrophages to kill parasites via NO, the exacerbated activation and sustained recruitment of immune cells including neutrophils, NK cells, Ly6C+ inflammatory monocytes, and CD4+ and CD8+ T lymphocytes induces a chronic inflammatory response; this chronic inflammation leads to tissue necrosis and skin damage, a feature of non-healing lesions [11–13].