The Amaxa Nucleofector technology is a transfection system designed to transfer genes into cells quickly and efficiently. The technology is based on electroporation. The Nucleofector device is essentially a cell electroporator that is programmed with various profiles that are defined electrical parameters for specific cell types. Each cell type is introduced to the DNA (or RNA) in an optimized Nucleofector solution that has been designed for that particular cell type. The user essentially selects the appropriate Nucleofector solution and program, mixes the Nucleofector solution with the nucleic acids, electroporates the cells with the optimally selected program, and achieves gene expression in as little as a few hours. Since the solutions and the programs are pre-configured by Amaxa, there is little optimization by the user. The only variable that exists in the beginning is titering the amount of nucleic acid that achieves the optimum results.
The transfection technology introduces the genetic material directly into the nucleus where it is incorporated into the cell independent of cell division. This is advantageous in that it reduces assay time to a couple of hours versus 24 to 48 hours for standard transfection technologies using liposome mediated delivery (i.e. standard luciferase assays and reporter constructs). In our hands, we have seen expression of proteins in as little as 4 hours using primary T cells. The system is ideally matched for selected primary cell populations, including T, B, NK, CD34+ hematopoetic cells, chondrocytes, cardiomyocytes, endothelial cells, keratinocytes, stem cells, neurons, and DC cells. Typically, primary cells are often difficult to transfect via non-viral means and often cannot be cultured for 48 hours without changing their functional properties. Although high transfection efficiencies are seen in cell lines such as Jurkats or NIH3T3, cell lines are usually easily transfected by most standard liposomal techniques. Still, the amount of time required for protein expression is far less than standard techniques. Efficiencies are determined by flow cytometry or microscopy (if a construct is tagged with a fluorescent protein or if co-transfected with a labeled control).
The Amaxa system is not restricted to DNA but can also be used for transferring siRNA into cells, especially primary cells. Since siRNA takes anywhere from 24-72 hrs to be effective, a fast delivery and interference is desired. The Nucleofector device is a small modern electroporator with easy to use finger controls. A very nice feature of the machine is that it can be upgraded with new programs as they are developed by Amaxa via a chip card that is provided with the device. The kits are suitable for 25 reactions and contain essentially everything: optimized Nucleofector solution and supplement, cuvettes and pipettes, optimized protocol and helpful kits. The list of available kits for mouse, human, and rat cells is continuously growing.
The only drawbacks to the machine are that if you have a cell system that has not been optimized by Amaxa, such as lab specific clones or cell lines, you will have to use trial and error on each of the programs provided and potentially buy several of the solutions that are sold. Another disadvantage is that you are never told what the Nucleofector solution actually contains. This may be important to know if there are optimizations required even in pre-configured cell kits. The cost of the kits is within reason, however you will have to buy the Nucleofector device which retails for about $10K (USD). Amaxa demos are available and include extensive on-site training and set up, very helpful technical support, and knowledgeable field representatives that follow up and are interested in helping you overcome any problems.
Overall, the Amaxa Nucleofector system and kits are extremely convenient, easy to use, and beneficial for primary cell research where non-viral gene transfer is required. It is also fast, so for easy to use, pre-configured kits that work especially well in primary samples, including patient sample material, it is highly recommended.
Omar Perez, Ph.D.
Center For Clinical Science Research