Abstract:Objective: Melphalan was used to evaluate the application of fluorescence imaging technique in retinoblastoma model of BALB/c-nu mice induced by Y79 cell line. Methods: BALB/c-nu mice transfected Y79 cells (1.0× 107 / mL, 3μL) with GFP injected in vitreous were modelled. On day 27, they were randomly divided into model control group and Melphalan group with different doses (1μg/ eye, 3μg/ eye, 10μg/ eye) according to fluorescence values in vivo, and were given single dose in vitreous body. Model control group was given equal volume 0.9% sodium chloride injection. Eye symptoms were observed daily during the trial. Slit-lamp examination was performed at 12, 20, 29, 35, 42, 48, 55, 76, 83d after modeling, and vivo imaging was performed at 12, 20, 27, 41, 48, 55, 62, 69, 76, 83d after modeling. After the final examination, the eye, brain and cerebellum tissues were extracted for histopathological examination. Results: At the beginning of the 6d of modeling, the cloud material was visible in the eyes of the animals. In the model control group, the cloud material occupied the entire eyeball in the later stage, accompanied by irregular growth of blood vessels, and finally caused eye rupture. After 27 days of modeling, the tumor fluorescence values of all the eyes reached the lower limit of in vivo imaging detection (10^5), and continued to increase with the extension of modeling time. From 69 to 83d of modeling, the tumor fluorescence values remained at the upper limit of in vivo imaging detection (10^7). Histological examination showed severe proliferation of intraocular tumor cells in the 83d model group and tumor cells in the brain of 1 model animal. 10μg Melphalan dose group could significantly reduce tumor fluorescence value 15 days after administration, and the inhibition rate remained above 98% until the end of the trial. The 3μg and 1μg Melphalan dose groups significantly inhibited the fluorescence value of eye tumor 30 days after administration, and the inhibition rates were 78.5% and 64.9%, respectively, until the end of the trial. No tumor cells were found in the brain tissue of animals in the Melphalan group. Conclusion: The retinoblastoma mouse model was established by injecting Y79/ PCDH-LUS-COPGFP cells into BALB/c-nu mice vitreous body. After the intervention of Melphalan with different concentrations, the fluorescence intensity of in vivo imaging was negatively correlated with the dose.
