Table 2. SIN analysis of the B-cell epitopes on PR8 HA compiled from the Immune Epitope Database (IEDB) is shown.

B-cell Epitope ID	Epitope residues	Numbering based on PR8 Crystal Structure	Does the epitope have SA-anchoring RBS residues with potential to modulate receptor-binding affinity upon antigenic mutation?
72805	WLTEKEGSYP	153–162	YES (P162, E156, E158)
77507	E169, G172, Q205, N206, Q209, E211	156, 159, 192, 193, 196, 198	YES (E156, Q192, N193, Q196, E198)
77508	L87, L88, V90, R91, S92, E132	74–75, 77–79, 119	YES (L74, L75, E119)
77509	P141, N142, E171, S173, P175, K176, K178, N179, S180	128–129, 158, 160, 162–163, 165–167	YES (P128, N129, E158, P162)
77510	S153, G156, S158, R237, D238	140,143,145,224–225	YES (G143, S145, R224)
77511	V182, G186, I195, S220, G253, S287	169 173 182 207 240 274	YES (I195)
12285	EGSYPKLKNSYVNK	158–171	YES (E158, P162, L164, K165, N166)
57751	SFERFEIFPKE	114–124	YES (E119)
71335	VTGLRNIPSIQSR	318–330	NO
71336	VTGLRNIPSIQSRGLFGAIAGFIEG	318–330 + 501–512	NO
76950	E170, E172	157, 159	YES (E157)
76990	I258	244	NO
76991	N245	231	NO
76992	P199	186	YES (P199)