id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-275608-joyan7ij	Sewell, Andrew K.	Why must T cells be cross-reactive?	2012-08-24		.txt	text/plain	7748	347	47	However, the repertoire of αβ T cell receptors (TCRs) is dwarfed by the vast array of potential foreign peptide–MHC complexes, and a comprehensive system requires each T cell to recognize numerous peptides and thus be cross-reactive. However, the repertoire of αβ T cell receptors (TCRs) is dwarfed by the vast array of potential foreign peptide-MHC complexes, and a comprehensive system requires each T cell to recognize numerous peptides and thus be cross-reactive. Box 1 | Extensive T cell cross-reactivity and apparent specificity are not incongruous From the 20 proteinogenic amino acids, it is possible to generate vast numbers of peptides of a length that can be presented by MHC molecules (see the table). First, a cross-reactive T cell repertoire generates a near perfect solution to the huge challenge of providing effective immune cover by allowing a limited number of T cells to provide immunity against virtually all foreign peptides that can bind to self MHC molecules.	./cache/cord-275608-joyan7ij.txt	./txt/cord-275608-joyan7ij.txt