Fluorescent LYVE-1 antibody to image dynamically lymphatic trafficking of cancer cells in vivo.
BACKGROUND
The lymphatic system is a major route for cancer cell dissemination, and a potential target for antitumor therapy. Despite ongoing interest in this area of research, the real-time behavior of cancer cells trafficking in the lymphatic system is poorly understood due to lack of appropriate tools to image this process.


METHODS
We have used monoclonal-antibody and fluorescence technology to color-code lymphatic vessels and the cancer cells inside them in a living animal. Monoclonal anti-mouse LYVE-1 antibody was conjugated to a green fluorophore and delivered to the lymphatic system of a nude mouse, allowing imaging of mouse lymphatics. Tumor cells engineered to express red fluorescent protein were then imaged traveling within the labeled lymphatics in real time.


RESULTS
AlexaFluor-labeled monoclonal anti-mouse LYVE-1 created a durable signal with clear delineation of lymphatic architecture. The duration of fluorescent signal after conjugated LYVE-1 delivery was far superior to that of fluorescein isothiocyanate-dextran or control fluorophore-conjugated IgG. Tumor cells engineered to express red fluorescent protein delivered to the inguinal lymph node enabled real-time tracking of tumor cell movement within the green fluorescent-labeled lymphatic vessels.


CONCLUSIONS
This technology offers a powerful tool for the in vivo study of real-time trafficking of tumor cells within lymphatic vessels, for the deposition of the tumor cells in lymph nodes, as well as for screening of potential antitumor lymphatic therapies.
McElroy
Michele
M
Department of Surgery, University of California, San Diego, California, USA.
Hayashi
Katsuhiro
K
Garmy-Susini
Barbara
B
Kaushal
Sharmeela
S
Varner
Judith A
JA
Moossa
A R
AR
Hoffman
Robert M
RM
Bouvet
Michael
M
D000818:Animals; D045744:Cell Line, Tumor; D002465:Cell Movement; D003952:Diagnostic Imaging / Q000379:methods*; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins; D006801:Humans; D008164:Luminescent Proteins; D008198:Lymph Nodes / Q000276:immunology / Q000473:pathology*; D042601:Lymphatic Vessels / Q000276:immunology / Q000473:pathology*; D026901:Membrane Transport Proteins; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness / Q000276:immunology / Q000473:pathology; D009360:Neoplastic Cells, Circulating; D010190:Pancreatic Neoplasms / Q000276:immunology / Q000473:pathology*; D012190:Retroviridae; D014161:Transduction, Genetic; D000097573:Red Fluorescent Protein
D006023:Glycoproteins; D008164:Luminescent Proteins; D026901:Membrane Transport Proteins; D000097573:Red Fluorescent Protein; C492273:LYVE1 protein, mouse