Brain-on-a-Chip Technology Aids CNS Drug Discovery

by Warren Grill, senior technical editor

Testing drugs that may have effects on neurons and brain circuits has typically required extensive in vivo experimentation in animals. Although in vitro testing on dissociated or cultured neurons offers an alternative to in vivo testing, these preparations lack the connections that occur within brain circuits, and single cells provide an incomplete picture of the effects of experimental compounds on the nervous system.

Irvine, CA-based Tensor Biosciences has created an alternative, called Brain-on-a-Chip technology, that takes advantage of neurotechnology to enable measurement of the effects of compounds on electrical activity within brain circuits.

The Brain-on-a-Chip technology is a platform for testing the effects of drugs on CNS neurons and circuits in living slices of brain tissue. The system is based around the MED64 system, originally developed by Panasonic, a subsidiary of the electronics giant, Matsushita Electric. The patented probe design is manufactured using photolithography and includes a two-dimensional array of 64 planar microelectrodes patterned on a culture plate. Each of the electrodes can be used to stimulate and record from slices of brain tissue that are cultured on top of the electrodes.

Tensor has developed proprietary methods for recording drug effects from brain slices cultured directly on the probe and kept alive for many days or even weeks. In addition, Tensor has a software interface that enables visualization of network activity across the slice, as well as methods to produce beta, gamma, and theta EEG rhythms within brain slices.

The company asserts that by enabling testing of drug effects on living neurons and circuits within a living brain slice, this technology will enable rapid discovery and testing of better and safer therapeutics. One of many potential applications of the Brain-on-a-Chip technology is the development of screening assays for identification of agents for the treatment of epilepsy, ischemic stroke, Alzheimer’s disease and other neurodegenerative disorders. Further, Tensor is developing a 16-chip system, called DS-MED, to increase the system’s throughput.
Tensor Biosciences, a privately held corporation that began operations in 2000, has partnered with Matsushita Electric, and in May 2002 entered a five-year agreement to develop and commercialize the Brain-on-a-Chip technology. Pursuant to this agreement, the drug testing assays developed by Tensor will be patented by Matsushita Electric and licensed exclusively back to Tensor for use in the discovery of new drugs.

For example, Tensor obtained an exclusive license from Matsushita for an in vitro chronic assay technology patent, entitled “Measurement of Complete Electrical Waveforms of Tissue or Cells” that relates to Tensor’s advanced brain slice culture methods and their application to multi-site electrophysiology. Further, anticipating growth in demand for the MED64 system, in April, 2002, Matsushita Electric set up a subsidiary company, Alpha MED Sciences Co., to lead the development, production, and worldwide marketing of the MED64 System.

Tensor’s management team includes Gary Lynch as chairman. Lynch is a renowned professor of neurobiology at University of California, Irvine, and founder of two other firms in the neuro space, Cortex Pharmaceuticals, Inc. and Synaptics, Inc. Jim Whitson serves as president and CEO of Tensor. He is an expert in computational neuroscience, pattern recognition, and neural networks, and previously ran his own privately held technology consulting company called Simcentric Systems.