Cross-presentation

The term cross-presentation denotes the ability of certain antigen-presenting cells to take up, process and present extracellular antigens with MHC class I molecules to CD8 T cells (cytotoxic T cells). Cross-priming describes the stimulation of naive cytotoxic CD8+ T cells by this process. This process is necessary for immunity against most tumors and against viruses that do not infect antigen-presenting cells.