IFN-γ production in response to predicted DR4 binding peptides in DR4-IE transgenic mice. DR4-IE transgenic mice were immunized with the indicated peptides and 10 days later their lymph node cells (4 × 105) were challenged in vitro with the same peptide (10 g/ml). The peptides human type II collagen (hCII) 316–333, hepatitis B surface antigen (HBsAg) 94–106, and HBsAg 159–171 did not elicit an IFN-γ response. Supernatants were tested for the presence of IFN-γ by enzyme-linked immunosorbent assay, as described in Materials and method. Data represents the average IFN-γ response ± SD of three mice. hAG, human aggrecan.