Biogen Idec Inc. has long been interested in the late stages of inflammation where tissue remodeling and fibrosis occur. Last week's deal with LigoCyte Pharmaceuticals Inc. adds another piece to the puzzle with a preclinical program targeting the CD103 integrin to treat chronic inflammatory diseases.

Integrins are part of a group of cell adhesion molecules that govern leukocyte binding and activation. They help direct leukocyte homing to sites of inflammation and also play an adhesive role in tissues, retaining leukocytes that have migrated to inflamed areas.