Chapter 19 Infections/Fig 19.16.jpg

You can download this figure by right-clicking it and choosing 'Save Picture As...'

Schematic outline of cell-mediated immunity. Macrophages present antigens to a CD4 + T cell via MHC class II molecules, while cytokines activate macrophages to epithelioid cells. The alternative activation route via NK cells is indicated. IFN = interferon; IL = interleukin; TNF = tumor necrosis factor.