Retroviral introduction of exogenous TCR-β chains in RCD cell line P1 restores TCR-αβ dimer formation and surface expression. SDS-PAGE analysis of immunoprecipitates obtained from digitonin lysates of T-cell clone N10 (left), RCD cell line P1 (middle), and RCD cell line P1 transduced with TCR-β from N10 (right) after cell surface iodination. Antisera used were normal rabbit serum as negative control (N), anti-HLA class I (C), anti-CD3γ (γ), anti-CD3δ (δ), and anti-CD3ϵ (ϵ). (Top panel) Reducing conditions. (Bottom panel) Nonreducing conditions. Positions of individual chains and molecular mass markers (kilodaltons) are indicated.