Datasets.

Dash data: The data set constructed by Dash et al. [10] contains epitope-spcefic TCRs for Epstein-Barr virus (EBV), human Cytomegalovirus (CMV), Influenza A virus (IAV) and mouse Cytomegalovirus (mCMV). VDJdb data: Data set gathered from VDJdb contains epitope-specific TCRs for Cytomegalovirus (CMV), Epstein-Barr virus (EBV), Influenza A virus (IAV), Hepatitis C virus (HCV), Herpes Simplex virus type 2 (HSV-2), Yellow Fever virus (YFV), Dengue virus type 1 (DENV1), Dengue virus type 3 (DENV3-4), and Human immunodeficiency virus type 1 (HIV-1). For the MHC chains we show here only the allele group. For some epitopes there are TCRs for which there exists more detailed information and some variation, which are shown in S3 File.