Ovarian cancer is the most lethal
malignancy affecting the female reproductive system. Identification and removal of all ovarian intraperitoneal
tumor deposits during the intraoperative surgery is important towards preventing
cancer recurrence and ultimately improving patient survival. Herein, we investigate the effectiveness of virus mimicking nanoparticles, derived from genome-depleted plant-infecting brome mosaic virus, and doped with near infrared (NIR) brominated cyanine
dye BrCy106-NHS, for targeted NIR fluorescence imaging of intraperitoneal ovarian
tumors. We refer to these nanoparticles as optical viral ghosts (OVGs). We functionalized the OVGs with
antibodies against HER2 receptor, a
biomarker over-expressed in
ovarian cancers. We injected functionalized OVGs, non-functionalized OVGs, and non-encapsulated BrCy106-NHS intravenously in mice implanted with ovarian intraperitoneal
tumors.
Tumors were extracted at 2, 6, and 24 h post-injection, and quantitatively analyzed using NIR fluorescence imaging. Fluorescence emission from
tumors associated with the injection of the functionalized OVGs continued to increase between 2 and 24 h post-injection. At 24 h timepoint, the average spectrally-integrated fluorescence emission from homogenized
tumors containing functionalized-OVGs was about 3.5 and 19.5 times higher than those containing non-functionalized OVGs or non-encapsulated BrCy106-NHS, respectively. Similarly, by using the functionalized-OVGs, the imaging signal-to-noise ratio at 24 h timepoint was enhanced by approximately threefold and sevenfold as compared to non-functionalized OVGs and the non-encapsulated
dye, respectively. These functionalized virus-mimicking NIR nano-constructs could potentially be used for intraoperative visualization of ovarian
tumors implants.