Nanostructured materials are used in vivo for dynamic therapies, such as drug delivery, tissue engineering, biosensing, and imaging. Nanowires and other nonparticulate nanostructured materials have been proposed to alter cellular attachment and motility, detect analytes in vivo, simulate tissue organization, and serve as an alternative stent topography. e interaction between nanostructured materials and elements of the body can be bene cial but can also lead to a variety of adverse immune responses ranging from bacterial infection to t umorigenesis. A p rimary concern with increased use of nanomaterials is safety, with regard to possible toxicity. Numerous studies have linked inhaled nanoparticles to a irway injury or diseases such as coronary diseases. e reported toxicity of nanoparticles brings into question the immunogenicity of nonparticulate nanomaterials. Numerous studies have focused on the in ammation response to pa rticulate na nomaterials such as na noparticles a nd carbon na notubes, but l ittle attention has been focused on the immune response to nanostructured materials, such as nanowires, nanoporous memb ranes, a nd na notubular su rfaces. Re cently, a n i ncreasing n umber o f s tudies h ave characterized t he in ammation re sponse of n anostructured m aterials b oth in v itro an d in v ivo. To understand the immune response to nanostructured materials, rst t he re sponse to at a nd na noparticulate materials will be reviewed.