A 14-foot aluminum alloy robot hurdles through the black of space at 13,000 miles per hour. For 350 million miles, its load of scientific instruments built t0 detect X-rays and analyze minerals sits isolated, periodically pinging the craft’s home planet. Eight months after lift-off, the craft nears its destination as a distant red dot becomes a looming planet: Mars. To successfully land, the $2.5 billion NASA Curiosity Rover must slow to .01% of its cruising speed, shield itself from heat, orient in a foreign planet’s atmosphere, activate a rocket backpack, and skycrane down like a robotronic version of Mission Impossible. Each maneuver is meticulously calculated and precisely executed, despite the fact that no human has ever been beyond Earth’s Moon. Until Elon Musk’s Mars dreams become a reality, rocket scientists will continue to rely on simulations to successfully understand and operate in environments that they themselves could never go.
Similar routes are taken in biology. A human has over 7,500 named parts and more than 60 organs. Most of these are deep within a living body, beyond the reach of monitoring and modern high-resolution imaging. Current observation and subsequent understanding of cellular microenvironments is limited — we can’t yet put tracking nanobots into a bloodstream or image through skull and brain to measure precise chemical changes within. So how can we make sense of the molecular systems that keep an organism alive or drive organs to disease?
A promising solution rests at the intersection of engineering and biology: microfluidics. Using tiny customized remixes of the classic biological petri dish, researchers can simulate conditions found in a body and control for specific variables such as enzyme changes or the presence of growth factors. In much the same way that NASA used simulations on Mars to successfully model and actually land the Curiosity Rover, researchers are beginning to replicate in vivo and in vitro scenarios to study anomalies including the growth and spread of tumors. Researchers can now directly observe small pieces of cancerous tissue breaking off, migrating through the bloodstream, and settling in capillaries. They can even test the efficacy of different drugs on those cancers without having to risk a life.
Cancer is just the beginning. MIT’s Roger Kamm expects that in the future we could grow and simulate organs from a patient’s own cells in order to test how he or she will respond to different medications. Microfluidics technology is also now being applied to neuroscience. It’s being used to study stages of development and decipher how variance in chemical and physical processes causes neurons to grow or recede. Take the well-studied case of neuromuscular junctions. These excitatory synapses allow you to willfully move your body and are found between a spinal motor neuron and a skeletal muscle fiber. Albert Folch of University of Washington points out that while “The sequence of molecular signals leading to synaptogenesis is qualitatively well known, little is known of the quantities (concentration, duration, onset, etc.) of the various neurochemical signals involved.” Microfluidics is changing that, opening windows into cellular microenvironments that control functions core to behavior. Scientists are able to use such circuits to test neuron computation and construct logic gates of out live cells.
Fundamental knowledge facilitates creative applications. Microfluidics researchers have recently begun developing biobots, hybrid robots that combine a flexible frame with live muscle cells. Kamm anticipates future biobots will be equipped with neuronal sensory systems and may one day be put to use in a wide variety of cases, such as being sent to seek and absorb chemical contaminants after an oil spill.
Tune in next week as MIT Neurotech explores the highest definition neuron maps mankind has ever known.
Editor’s note: This is the third installment in a series about emerging neurotechnologies. Join a pilot class of 12 PhD students at MIT as we explore how neuroscience is revolutionizing our understanding of the brain. Each post coincides with a lecture and lab tour at MIT created by the Center for Neurobiological Engineering. This experiment is supported by MITx and created by EyeWire.