Novel peptide sequence ("IQ-tag") with high affinity for NIR fluorochromes allows protein and cell specific labeling for in vivo imaging.
BACKGROUND
Probes that allow site-specific protein labeling have become critical tools for visualizing biological processes.


METHODS
Here we used phage display to identify a novel peptide sequence with nanomolar affinity for near infrared (NIR) (benz)indolium fluorochromes. The developed peptide sequence ("IQ-tag") allows detection of NIR dyes in a wide range of assays including ELISA, flow cytometry, high throughput screens, microscopy, and optical in vivo imaging.


CONCLUSIONS
The described method is expected to have broad utility in numerous applications, namely site-specific protein imaging, target identification, cell tracking, and drug development.
Kelly
Kimberly A
KA
Center for Molecular Imaging Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America.
Carson
Jonathan
J
McCarthy
Jason R
JR
Weissleder
Ralph
R
D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000737:chemistry; D004396:Coloring Agents; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005434:Flow Cytometry / Q000379:methods; D005456:Fluorescent Dyes; D008856:Microscopy, Fluorescence / Q000379:methods; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D013055:Spectrophotometry, Infrared / Q000379:methods
D004396:Coloring Agents; D005456:Fluorescent Dyes; D010455:Peptides