Figure 1.

Cross-conservation between T-cell receptor facing residues of Tcell epitopes may influence immune response. Pathogens may exploit cross-conservation with self to reduce immune recognition of pathogen epitopes. Cross-reactivity with the human microbiome has also been observed. The sum or ratio of these influences may determine the phenotype of the responding T cells. Understanding cross-conservation of the T cell epitope and its context is critically important for understanding human immune responses to infection and vaccination.