Abstract:

Objective To investigate the feasibility of monitoring islet cells with baculovirus as vector and sodium iodine symporter (NIS) gene as report gene. Methods Green fluorescent protein (GFP) and NIS gene baculovirus (Bac-GFP and Bac-NIS) were produced according to Bac-to-Bac baculovirus expression system. The rat islet cells were isolated and infected by Bac-GFP at different multiplicities of infection (MOI), and the infection percentage and fluorescence intensity were observed with fluorescence microscope. The islet cells were infected by Bac-GFP at MOI of 40, and the florescence protein expression time and cell survive state were observed with fluorescence microscope. The islet cells were infected by Bac-NIS at different MOI, and the iodide uptake of infected cells was determined. The islet cells were infected by Bac-NIS at MOI of 40, and the iodide uptake and effect of natrium perchloricum (NaClO4) on iodide uptake of infected cells were  dynamically observed. Results Bac-GFP could effectively infect SD rat islet cells, with no cytotoxicity. Both infection percentage and fluorescence intensity of islet cells increased with MOI, the infection percentage could be as high as 95% at MOI of 40, and fluorescence microscopy revealed that the florescence protein expression time could last for about two weeks. Bac-NIS infected islet cells exhibited enhanced iodide uptake function and inhibition property of NaClO4. The radioactive iodine uptake of infected cells increased with MOI. At MOI of 40, the radioactive count of iodide uptake of Bac-NIS infected cells was as 12 times as that of control group. Conclusion Recombinant NIS gene baculovirus can highly express in islet cells and effectively mediate iodine uptake of infected islet cells, which may provide a potent method to monitor the islet cell transplantation.

Key words: baculovirus, sodium iodine symporter, islet cell, report gene