Figure 1.

Secretion and folding of conventional λ light chain (Cλ), surrogate light chain, and λ5/14.1 (A) COS7 cells were transfected with expression vectors as indicated. After metabolic labeling, both lysates and supernatants were immunoprecipitated with goat anti-λ antiserum and separated in a 12.5% SDS/PAGE gel under reducing conditions. The migration of molecular mass markers is indicated on the right margin (kDa). (B) COS7 cells were transfected with the vectors indicated then lysed in the absence (−) or presence (+) of NEM. Proteins were immunoprecipitated with goat anti-λ and analyzed under nonreducing (N) or reducing (R) conditions.