Table 1.

mAB 25-9-17 shows selective recognition of some A^b–peptide complexes

	% inhibition of T cells response by mAb
Peptide [source]	Y3JP	25-9-17	YAe
Endogenous peptides*
Unknown +Ab (D10 allo)	99	99.5	0
SAKPVSQMRMATPLLMRPMSM (CLIP) + linker + Ab	99	98	0
Unknown +Ab (D10 allo), Ii KO	95	73.5	0
Exogenously added peptides†
RNIYWTDSVPGSVSVA [LDL receptor, residues 486–501]	100	100	0
TQFHPPHIEIQ [β2-microglobulin, residues 48–58]	100	100	0
ITNQYNSPTGLYSSKN [Clp36, residues 138–154]	100	49	0
VPIYEGYALPHAILR [β-actin, residues 48–56]	100	38	0
NLCNIPASALLSSDIP [hen-egg lysozyme, residues 74–88]	100	43	0
APMYYRGAQAAIVVYD [Rab5, residues 86–101]	100	52	0
ASFEAQGALANIAVDKA [Eα52–68]‡	97.4	0	97
TKNLDYVATSIHEAVT [aspartate aminotransferase, residues  396–410]	98	−3.5	0
GENPIYKSAVTTVVNPK [integrin β1, residues 778–794]	100	8.5	0
GQNAWFLPAQADIVATK [CD98, residues 207–223]	100	−9	0
DWTVDHPQTLFAWEG [CD22, residues 25–39]	95	16	0

^*Proliferation of D10 T cells in response to endogenous peptides was blocked by addition of purified mAbs (5 μg/ml). Percent of inhibition is shown relative to addition of equal concentration of YAe as a negative control. Mean of two separate experiments. 

^†Inhibition of IL-2 secretion by T cell hybridomas, measured by proliferation of IL-2-dependent cells, was estimated. T cell hybridomas were generated against synthetic analogues of peptides presented naturally by A^b (refs. 13 and 24 and A.Y.R., unpublished results). Data are from representative experiments. Inhibition was calculated relative to equal concentrations of the anti-class I mAb Y-3. Both peptides and antibodies were titrated. The data for 25-9-17 represent maximal achievable inhibition. This was measured at a peptide concentration when the response is clearly detectable and is below saturation and at a maximal concentration of mAb showing inhibition. The data for Y3JP and YAe are shown for the same peptide and mAb concentrations as for 25-9-17 for every T cell. 

^‡1.H3.1 T cell hybridoma (13) was used to test anti-A^b–pEα response.