This Jan. 24, 2015, file photo, shows the exterior of AbbVie, in Lake Bluff, Illinois. (AP Photo / Nam Y. Huh, File)

The two pharmaceutical companies have little in common, save for a desire to reinvigorate growth that has sputtered. 

AbbVie, the research arm of Abbott Laboratories, bought the Dublin-based Shire pharmaceutical company last Friday for nearly $55 billion. We break down the economic impact this move will have on Chicago.