ANTIGEN PRESENTATION

Antigen presentation is a process in the body's immune system by which macrophages, dendritic cells and other cell types capture antigens and then enable their recognition by T-cells. The basis of adaptive immunity lies in the capacity of immune cells to distinguish between the body's own cells, and infectious pathogens. The host’s cells express “self” antigens that identify them as such. These antigens are different from those in bacteria ("non-self" antigens) or in virally-infected host cells (“missing-self”). The ability of the adaptive immune system to survey for infection requires specialized pathways of enabling recognition of pathogen-derived antigens by T cells.
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