A novel near-infrared fluorescence imaging probe that preferentially binds to cannabinoid receptors CB2R over CB1R.
The type 2 cannabinoid receptors (CB2R) have gained much attention recently due to their important regulatory role in a host of pathophysiological processes. However, the exact biological function of CB2R and how this function might change depending on disease progression remains unclear and could be better studied with highly sensitive and selective imaging tools for identifying the receptors. Here we report the first near infrared fluorescence imaging probe (NIR760-XLP6) that binds preferentially to CB2R over the type 1 cannabinoid receptors (CB1R). The selectivity of the probe was demonstrated by fluorescence microscopy using DBT-CB2 and DBT-CB1 cells. Furthermore, in mouse tumor models, NIR760-XLP6 showed significantly higher uptake in DBT-CB2 than that in DBT-CB1 tumors. These findings indicate that NIR760-XLP6 is a promising imaging tool for the study of CB2R regulation.
Department of Radiology, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA.
Xiaoxi
X
Ling
Department of Radiology, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA.
Shaojuan
S
Zhang
Department of Radiology, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA.
Pin
P
Shao
Department of Radiology, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA; Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
Weixia
W
Li
Department of Radiology, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA; Cellular and Genetic Medicine Department, Basic Medical School, Fudan University, Shanghai 200032, China.
Ling
L
Yang
Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA 15261, USA.
Ying
Y
Ding
Department of Pharmacology, Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA.
Cong
C
Xu
Department of Pharmacology, Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA.
Nephi
N
Stella
Department of Radiology, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA; University of Pittsburgh Cancer Institute, Pittsburgh, PA 15232, USA. Electronic address: baim@upmc.edu.
Mingfeng
M
Bai
D000818:Animals; D005260:Female; D005456:Fluorescent Dyes / Q000737:chemistry* / Q000378:metabolism; D051379:Mice; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology*; D061848:Optical Imaging; D043882:Receptors, Cannabinoid / Q000032:analysis* / Q000378:metabolism; D051598:Whole Body Imaging
D005456:Fluorescent Dyes; D043882:Receptors, Cannabinoid
CB(2) receptor; Cancer; Cannabinoid; Fluorescence imaging; Near infrared