Fig. 2.
Quantitation of CTCs by both in vivo imaging of animal models and ex vivo flow cytometry of peripheral blood samples from ovarian cancer patients. (a) Change in CTCs as a function of time after M109 tumor cell implantation. CTCs were quantitated by measuring the number of fluorescent tumor cells per minute flowing through a blood vessel in the ear of each mouse. Red bars represent mean values. (b) Method of image processing. One thousand line scans, spanning a 2-s time period, across a blood vessel are combined sequentially by using MATLAB software to yield the displayed image. (c) CTC counts in peripheral blood samples from 12 ovarian cancer patients with different pathologies. Red bars represent mean values from multiple independent measurements. (d) Confocal images of single CTC in blood smears from an ovarian cancer patient. Overlap of green (folate-AlexaFluor 488) with red (rhodamine-X-labeled anti-cytokeratin antibody) fluorescence is displayed as yellow fluorescence. (Scale bar: 10 μm.) (e) Comparison of the labeling intensities of folate-FITC (green) and three different polyclonal anti-FR antibodies conjugated with FITC: PU9 (red), PU10 (yellow), and PU17 (navy). Unlabeled KB cells (black) and KB cells incubated with 10 μM folic acid plus 100 nM folate-FITC (orange, totally competed) serve as negative controls.