Regeneron Pharmaceuticals, Inc.
HUMAN LAMBDA LIGHT CHAIN MICE

Abstract:

Genetically modified mice are provided that express human .lamda. variable (hV.lamda.) sequences, including mice that express hV.lamda. sequences from an endogenous mouse .lamda. light chain locus, mice that express hV.lamda. sequences from an endogenous mouse .kappa. light chain locus, and mice that express hV.lamda. sequences from a transgene or an episome wherein the hV.lamda. sequence is linked to a mouse constant sequence. Mice are provided that are a source of somatically mutated human .lamda. variable sequences useful for making antigen-binding proteins. Compositions and methods for making antigen-binding proteins that comprise human .lamda. variable sequences, including human antibodies, are provided.