Single neuron electroporation in manipulating and measuring the central nervous system

Effects of Cisplatin Electrochemotherapy on Human Neuroblastoma Cells

Electrochemotherapy is the usage of electroporation to introduce chemotherapeutic drugs through membrane pores into target cells for cancer treatment. The effectiveness of chemotherapeutic drugs would be increased dramatically when they are used in electrochemotherapy than standard chemotherapy. In the present study, we investigated the effects of cisplatin treatment with electroporation on human SH-SY5Y neuroblastoma cells. SH-SY5Y cells were treated with different concentrations (0.15-24 µg/mL) of cisplatin and then exposed to 1500 volts per centimeter (V/cm), 100 microseconds (µs) pulse duration, and 1 Hertz (Hz) electric pulses. Cisplatin alone showed a dose-dependent effect on cell viability. On the other hand, cisplatin + electroporation treatment was more effective than cisplatin treatment alone. Lower doses of cisplatin treatment with electroporation was as effective as higher doses of cisplatin treatment without electroporation. These results indicated that cisplatin cytotoxicity was potentiated after exposure of cells to high intensity electric pulses and low doses of cisplatin can be used with electroporation in the treatment of neuroblastoma.

A Simple and Efficient In Vivo Non-viral RNA Transfection Method for Labeling the Whole Axonal Tree of Individual Adult Long-Range Projection Neurons

We report a highly efficient, simple, and non-infective method for labeling individual long-range projection neurons (LRPNs) in a specific location with enough sparseness and intensity to allow complete and unambiguous reconstructions of their entire axonal tree. The method is based on the "in vivo" transfection of a large RNA construct that drives the massive expression of green fluorescent protein. The method combines two components: injection of a small volume of a hyperosmolar NaCl solution containing the Pal-eGFP-Sindbis RNA construct (Furuta et al., 2001), followed by the application of high-frequency electric current pulses through the micropipette tip. We show that, although each component alone increases transfection efficacy, compared to simple volume injections of standard RNA solution, the highest efficacy (85.7%) is achieved by the combination of both components. In contrast with the infective viral Sindbis vector, RNA transfection occurs exclusively at the position of the injection micropipette tip. This method simplifies consistently labeling one or a few isolated neurons per brain, a strategy that allows unambiguously resolving and quantifying the brain-wide and often multi-branched monosynaptic circuits created by LRPNs.