Basic study of an agent for reinforcement of near-infrared fluorescence on tumor tissue.
OBJECTIVE
An indocyanine green derivative (ICG-sulfo-OSu) and agents for reinforcement of infrared fluorescence, which can be used as an infrared fluorescent labeling substance suitable for detection of microlesions by an IR fluorescence endoscope, have been developed. The study aims were to confirm the ability of a reinforcement agent, as well as imaging processing, to intensify fluorescence from the labeled antibody on immunohistochemical staining.


METHODS
ICG-sulfo-OSu-labeled MUC1 antibody and an IR fluorescence imaging system were employed in the present study. Paraffin sections of gastric cancer were stained with anti-MUC1 antibody by the avidin-biotinylated peroxidase complex method. Among the positive specimens, three cases were used for IR imaging analysis. Octylglucoside was used as a reinforcement agent.


RESULTS
The incubation of paraffin sections with ICG-sulfo-OSu-labeled MUC1 antibody resulted in positive staining of the tumor sites by an IR fluorescence imaging system, and the intensity of fluorescence was increased depending on the concentration of octylglucoside and grade of imaging processing.


CONCLUSIONS
A reinforcement agent, and image processing, intensify a labeled antibody excitable by infrared fluorescence in tumor sections and can generate a strong enough fluorescent signal to detect small cancers when examined with an infrared fluorescence endoscope.
Second Department of Internal Medicine, University of Tokushima School of Medicine, 3-18-15 Kuramoto-cho, Tokushima City 770-803, Japan.
K
K
Inayama
S
S
Ito
N
N
Muguruma
Y
Y
Kusaka
T
T
Bando
Y
Y
Tadatsu
M
M
Tadatsu
K
K
Ii
S
S
Shibamura
K
K
Takesako
D000230:Adenocarcinoma / Q000737:chemistry* / Q000175:diagnosis; D000911:Antibodies, Monoclonal; D005456:Fluorescent Dyes; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D007208:Indocyanine Green / Q000031:analogs & derivatives*; D018396:Mucin-1 / Q000032:analysis / Q000276:immunology; D013050:Spectrometry, Fluorescence; D019265:Spectroscopy, Near-Infrared; D013274:Stomach Neoplasms / Q000737:chemistry* / Q000175:diagnosis
D000911:Antibodies, Monoclonal; D005456:Fluorescent Dyes; D018396:Mucin-1; C113792:indocyanine green-sulfo-OSu; D007208:Indocyanine Green