title: Inflammatory response to intravitreal injection of gold nanorods.
abstract: OBJECTIVE
  To evaluate the utility of gold nanorods (AuNRs) as a contrast agent for ocular optical coherence tomography (OCT).
  
  
  METHODS
  Mice were intravitreally injected with sterile AuNRs coated with either poly(strenesulfate) (PSS-AuNRs) or anti-CD90.2 antibodies (Ab-AuNRs), and imaged using OCT. After 24 h, eyes were processed for transmission electron microscopy or rendered into single cell suspensions for flow cytometric analysis to determine absolute numbers of CD45(+) leukocytes and subsets (T cells, myeloid cells, macrophages, neutrophils). Generalised estimation equations were used to compare cell counts between groups.
  
  
  RESULTS
  PSS-AuNRs and Ab-AuNRs were visualised in the vitreous 30 min and 24 h post-injection with OCT. At 24 h, a statistically significant increase in leukocytes, comprised primarily of neutrophils, was observed in eyes that received either AuNR in comparison to eyes that received saline. The accumulation of leukocytes was equal in eyes given PSS-AuNR or Ab-AuNR. Endotoxin-resistant C3H/HeJ mice also showed ocular inflammation after injection with AuNRs, indicating that the inflammatory response was not due to lipopolysaccharide contamination of AuNRs.
  
  
  CONCLUSIONS
  Although AuNRs can be visualised in the eye using OCT, they can induce ocular inflammation, which limits their use as a contrast agent.
authors.affiliation: Department of Ophthalmology, UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Gabriele Sandrian
authors.forename: Gadi
authors.initials: G
authors.lastname: Wollstein
authors.forename: Joel S
authors.initials: JS
authors.lastname: Schuman
authors.forename: Richard A
authors.initials: RA
authors.lastname: Bilonick
authors.forename: Yun
authors.initials: Y
authors.lastname: Ling
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Larry
authors.initials: L
authors.lastname: Kagemann
authors.forename: Kyle C
authors.initials: KC
authors.lastname: McKenna
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005434:Flow Cytometry; D006046:Gold / Q000008:administration & dosage*; D007249:Inflammation / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D058449:Intravitreal Injections; D007962:Leukocytes / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D046529:Microscopy, Electron, Transmission; D043942:Nanotubes; D041623:Tomography, Optical Coherence; D014822:Vitreous Body / Q000187:drug effects / Q000648:ultrastructure*
chemical_list: D006046:Gold