|
1
|
Zhou Q, Li Z, Zhou J, Joshi BP, Li G, Duan X, Kuick R, Owens SR, Wang TD. In vivo photoacoustic tomography of EGFR overexpressed in hepatocellular carcinoma mouse xenograft. PHOTOACOUSTICS 2016; 4:43-54. [PMID: 27766208 PMCID: PMC5066077 DOI: 10.1016/j.pacs.2016.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/08/2016] [Accepted: 04/18/2016] [Indexed: 05/24/2023]
Abstract
EGFR is a promising cell surface target for in vivo imaging that is highly overexpressed in hepatocellular carcinoma (HCC), a common cancer worldwide. Peptides penetrate easily into tumors for deep imaging, and clear rapidly from the circulation to minimize background. We aim to demonstrate use of an EGFR specific peptide to detect HCC xenograft tumors in mice with photoacoustic imaging. Nude mice implanted with human HCC cells that overexpress EGFR were injected intravenously with Cy5.5-labeled EGFR and scrambled control peptides respectively. Photoacoustic images collected from 0 to 24 h. Photoacoustic signal peaked in tumors at 3 h post-injection. Images from 0 to 1.8 cm beneath the skin revealed increased target-to-background (T/B) ratio from tumors. The T/B ratio was significantly greater for the EGFR versus control peptide. Clearance of signal was observed by ∼24 h. EGFR overexpression was validated with immunofluorescence and immunohistochemistry. A peptide specific for EGFR delivered systemically can detect HCC xenograft tumors in vivo with photoacoustic imaging.
Collapse
Affiliation(s)
- Quan Zhou
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, United States
| | - Zhao Li
- Department of Hepatobiliary Surgery, Peking University People’s Hospital, Beijing, China
| | - Juan Zhou
- Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Bishnu P. Joshi
- Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Gaoming Li
- Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Xiyu Duan
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, United States
| | - Rork Kuick
- Department of Biostatistics, University of Michigan, Ann Arbor, MI 48109, United States
| | - Scott R. Owens
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Thomas D. Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, United States
| |
Collapse
|
|
2
|
Abstract
We report the implementation of an image sensor chip, termed wavefront image sensor chip (WIS), that can measure both intensity/amplitude and phase front variations of a light wave separately and quantitatively. By monitoring the tightly confined transmitted light spots through a circular aperture grid in a high Fresnel number regime, we can measure both intensity and phase front variations with a high sampling density (11 microm) and high sensitivity (the sensitivity of normalized phase gradient measurement is 0.1 mrad under the typical working condition). By using WIS in a standard microscope, we can collect both bright-field (transmitted light intensity) and normalized phase gradient images. Our experiments further demonstrate that the normalized phase gradient images of polystyrene microspheres, unstained and stained starfish embryos, and strongly birefringent potato starch granules are improved versions of their corresponding differential interference contrast (DIC) microscope images in that they are artifact-free and quantitative. Besides phase microscopy, WIS can benefit machine recognition, object ranging, and texture assessment for a variety of applications.
Collapse
Affiliation(s)
- Xiquan Cui
- Department of Electrical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
| | | | | | | |
Collapse
|