TABLE 1.

Recognition of PBMC Pulsed with Recombinant gp 100 Protein by HLA-DRβ1^*0701 and -DRβ1^*0401 Restricted, gp 100-Reactive CD4⁺ T Cell Populations^*

Target Cells	HLA-DR Expression	Preloaded Protein^†	Introduced Gene^‡	BR-B8^§	B104^\|\|
Media	None	—	None	0	0
293-DR4	DR4⁺	—	MART-1	52	nt
293-DR4	DR4⁺	—	gp100	1,908	nt
293-DR7	DR7⁺	—	MART-1	0	1
293-DR7	DR7⁺	—	gp100	20	4,349
F002Rmel CIITA	DR7⁺	—	GFP	16	12
F002Rmel CIITA	DR7⁺	—	gp100	11	13,686
624mel CIITA	DR4⁺ DR7⁺	—	—	2,278	354
1861mel CIITA	DR4⁺	—	—	5,746	5
Donor 1 PBMC	DR4⁺ DR7⁺	—	—	16	0
Donor 1 PBMC	DR4⁺ DR7⁺	NY-ESO-1	—	25	1,107
Donor 1 PBMC	DR4⁺ DR7⁺	gp100	—	6,151	15,123
Donor 2 PBMC	DR4⁺ DR7⁺	—	—	27	12
Donor 2 PBMC	DR4⁺ DR7⁺	NY-ESO-1	—	37	428
Donor 2 PBMC	DR4⁺ DR7⁺	gp100	—	5,956	12,500
Donor 3 PBMC	DR4⁺ DR7⁺	—	—	37	23
Donor 3 PBMC	DR4⁺ DR7⁺	NY-ESO-1	—	13	225
Donor 3 PBMC	DR4⁺ DR7⁺	gp100	—	2,818	6,850

INF-γ secretion (pg/mL) in 20-hour coculture supernatants of target cells with T lymphocytes.

^†

Recombinant proteins were preloaded onto PBMC at 10 νg/mL overnight at 37°C.

^‡

The indicated genes were transfected into 293 cells or retrovirally transduced into F002mel CIITA cells.

^§

BR-B8 is a CD4⁺ T cell line that specifically recognizes gp100:44–59 in the context of HLA-DRβ1*0401.

^||

B104 is a CD4⁺ T cell clone that specifically recognizes gp100:170–190 in the context of HLA-DRβ1*0701.

Note. Underlined values indicate that INF-γ secretion in response to target cells expressing gp100 and either HLA-DRβ1*0701 or HLA-DRβ1*0401 was ≥ 100 pg/mL and at least twice background with relevant control target cells.