pFUSE2-CLIg-hK pFUSE2-CLIg-hK is a cloning plasmid that expresses the constant region of the human kappa light chain. It contains a multiple cloning site upstream of the constant region to enable cloining of the light chain variable region. This plasmid is designed for antibody generation when co-transfected into mammalian cells with the heavy chain variable region cloned into pFUSE-CHIg. pFUSE2ss-CLIg-hK additionally features the IL2 signal sequence to allow the secretion of recombinant antibodies generated using fragment antigen-binding (Fab) or single-chain variable fragment (scFv) fragments selected from phage display libraries that lack a signal sequence. • pFUSE2-CLIg-hK features the constant region of the human Ig kappa light chain • pFUSE2ss-CLIg-hK features the constant region of the human Ig kappa light chain and the IL2 signal sequence Both plasmids are selectable with blasticidin.