A multiple disciplinary research team in Boston College has pioneered CNT-mediated molecule delivery into mammalian cells. The team’s recent work on the biocompatibility of CNTs in primary lymphocytes has been published in issue 36, volume 18 of Nanotechnology. The researchers used CNTs grown by a plasma enhanced chemical vapor deposition technique to deliver DNA molecules into B lymphocytes via a process termed nanospearing. The CNT contains a Ni particle encapsulated at one end, allowing it to be driven by magnetic force into cell plasma membranes, thereby delivering into cells the molecule DNA (coupled to the exterior surface of the CNT). This delivery platform exhibits highly efficient transfection in several difficult-to-transfect mammalian cells such as ex vivo primary B lymphocytes and primary neurons. NanoLab Inc., a private company in Massachusetts, had participated in the study.
"Nanospearing holds promises for drug delivery and may provide a novel approach for vaccination", said Dr. Dong Cai, a Research Associate Professor in nano-biotechnology and PI of the project, "However, questions of biocompatibility of the delivery system need to be answered before the research can progress to human cells and tissues". The research team undertook a comprehensive investigation in mouse B lymphocytes to examine the biocompatibility of the delivery system. Using flow cytometry, the researchers investigated several parameters of B-cell activation and proliferation. It turned out the CNT-based delivery platform did not trigger non-specific activation of naïve primary B cells nor was there any sign of decreased survival or apoptosis. "Currently, there is no method to transduce naïve primary B cells", said Dr. Thomas Chiles who is an immunologist and co-author. Chiles added, "retroviral-mediated transduction is currently the method of choice, however, transduction requires that B cells are first stimulated by mitogens. The method developed by our team yields high efficiency of DNA delivery in unmanipulated ex vivo B cells".
This work is supported by National Institute of Biomedical Imaging and Bioengineering. In addition to the molecular delivery, Dr. Cai is also funded for studying CNT-based biosensor and biointerface.