Inflammatory response to intravitreal injection of gold nanorods
- Michelle Gabriele Sandrian1,2,3,
- Gadi Wollstein1,
- Joel S Schuman1,2,3,
- Richard A Bilonick1,
- Yun Ling1,
- Hiroshi Ishikawa1,2,
- Larry Kagemann1,2,
- Kyle C McKenna1,4
- 1Department of Ophthalmology, UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- 2Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- 3Center for the Neural Basis of Cognition, Carnegie Mellon University and University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- 4Department of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Correspondence to Dr Gadi Wollstein, UPMC Eye Center, 203 Lothrop Street, Eye and Ear Institute, Room 834.1, Pittsburgh, PA 15213, USA; , or Dr Kyle C McKenna, UPMC Eye Center, 203 Lothrop Street, Eye and Ear Institute, Room 910, Pittsburgh, PA 15213, USA;
- Accepted 23 September 2012
- Published Online First 19 October 2012
Aim 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.