Table 1.

Minimum size of Eα-peptide capable of stimulating the H12.25 T cell hybridoma

Amino acid residues of the Eα peptide																	T cell stimulation
52	53	54	55	56	57	58	59	60	61	62	63	64	65	66	67	68
A	S	F	E	A	Q	G	A	L	A	N	I	A	V	D	K	A	1
A	S	F	E	A	Q	G	A	L	A	N	I	A	V	D	K		2
A	S	F	E	A	Q	G	A	L	A	N	I	A	V	D			4
A	S	F	E	A	Q	G	A	L	A	N	I	A	V				8
A	S	F	E	A	Q	G	A	L	A	N	I	A					10
A	S	F	E	A	Q	G	A	L	A	N	I						175
	S	F	E	A	Q	G	A	L	A	N	I	A	V	D	K	A	1
		F	E	A	Q	G	A	L	A	N	I	A	V	D	K	A	1
			E	A	Q	G	A	L	A	N	I	A	V	D	K	A	10
			E	A	Q	G	A	L	A	N	I	A					>250
				A	Q	G	A	L	A	N	I	A	V				>250
				A	Q	G	A	L	A	N	I	A					(−)
		F	E	A	Q	G	A	L	A	N	I	A	V				2

Truncated peptides of the 52-68 Eα-wild-type peptide were tested for their capacity to stimulate the production of IL-2 by Eα 12.25 T cell hybridoma. T cell stimulation refers to the concentration of peptide that gave 50% of the maximum T cell response compared to the wild-type peptide Eα 52-68 (stimulation equal to 1). The 50% of the maximum T cell response was reached with 0.4 μM of wild-type peptide.