An engineered lipocalin specific for CTLA-4 reveals a combining site with structural and conformational features similar to antibodies.

ABSTRACT: Biomolecular reagents that enable the specific molecular recognition of proteins play a crucial role in basic research as well as medicine. Up to now, antibodies (immunoglobulins) have been widely used for this purpose. Their predominant feature is the vast repertoire of antigen-binding sites that arise from a set of 6 hypervariable loops. However, antibodies suffer from practical disadvantages because of their complicated architecture, large size, and multiple functions. The lipocalins, on the other hand, have evolved as a protein family that primarily serves for the binding of small molecules. Here, we show that an engineered lipocalin, derived from human Lcn2, can specifically bind the T cell coreceptor CTLA-4 as a prescribed protein target with subnanomolar affinity. Crystallographic a

SUBMITTER: Schonfeld D 

PROVIDER: S-EPMC2688850 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature