The transgenic construct expresses a T cell receptor raised against hemagglutinin (HA) from influenza virus A/SW/33(SW), which contains an analog of the S1 determinant that differs from S1 by 2 substitutions, R to K at residue 113 and E to T at residue 120, isolated from hybridoma S106-1. This receptor is encoded by TCR Valpha8.3 and Vbeta10, and has a much lower affinity for the original S1 determinant than does Tg(Tcra/Tcrb)1Vbo .