Table 4.

Effects of Amino Acid Substitutions on Binding of HEL 12–22 to I-A^g7

		Relative position (HEL 12–22)
		1M		2K		3R		4H		5G		6L		7D		8N		9Y		10R		11G
Well-tolerated residues		A		A		A		A		A		I		A		A		F		A		A
(IC50 <1,000 nM)		D		D		K		K		Q		M		E		G		K		D		D
		K		Q		L		L		Y		V		K		P		R		K		P
		L		Y		Q		Q						L		S				L		Q
		Q				Y		Y						P						P		Y
		Y												Q						Q
														R						Y
														Y
Weakly tolerated residues		P		L		D		D		D		D				D		D				K
(IC50 1,000–10,000 nM)				P		G		P		K		F				E		H				L
						P				L		H				F		L
						W				P		K				K		M
						S						N				L		N
												T				Q		Q
												Y				R		W
Nontolerated						E						A				W		A
(IC50 >10,000 nM)						F						E				Y		E
												G						G
												P						I
												Q						P
												R						S
												S						T
												W						V