Lasers in Space Part 2: Biological Sampling and Cell Counting in Space
The development and use of lasers in biological and medical research has provided a deeper understanding of diseases, organisms, pathogens, cellular structure of many life forms, and has enabled scientists to develop new ways of detecting and treating diseases. Optical biomedical imaging technologies enable the visualizing of tissues, cells and molecules in nano-scale, and super-resolution techniques up to the scale of complete organs use the principles of diffuse optical tomography. In the second part of our 'Lasers in Space' series, we take a look at biomedical research carried out as part of manned space missions, and the long-term impact it will have on space exploration.
NASA's Human Research Program looks into ways of quantifying human health and performance risks of crews during space missions. However, preserving biological samples in specialized containers to bring back for proper analyses meant that the mission compromises on the amount of fuel it can carry. What was required was technology capable of in-flight biological sample preservation and analysis under ambient temperatures. Accurate biomedical diagnosis, treatment and research of health-related issues in human crew members depends entirely on maintaining the integrity of the blood and tissue samples.
One way of achieving this is through NASA-developed Dried Chemistry Technology, which involves collecting fresh samples in certified tubes and applying them to filter-cards. These filter cards are then dried and stored for up to several months. Cell-counting and analyses refers to the identification and enumeration of various populations of white blood cells, which can indicate the presence of an infection or localized inflammation. This is achieved by means of flow-cytometry that requires pre-staining of certain cell proteins with fluorescent dyes, the emission of which will be optically detected by the cytometer upon excitation with an onboard laser. NASA has been working on the development of a microgravity compatible sample processing system that can stain, lyse and process blood samples while still being lightweight and portable.
In recent years, there have been several biological research initiatives carried out on the International Space Station. One is the Light Microscopy Module (LMM) that aims to study plant biology and root development in space, the latter being achieved by measuring fluorescent markers that were genetically programmed into the plant's DNA. A miniaturized laser-equipped imaging apparatus allowed live-cell imaging of the biomarkers. This study will be the pathway to growing vegetables and other plants in space, thereby allowing longer missions. More cutting edge research in space biology is being done in liquid preservative development that will enable sample preservation up to 6 months in-orbit, as well as in miniaturized portable DNA sequencing devices that can be carried on board.
NASA's Space Biosciences initiative in association with many international research bodies and universities will continue to advance research in space biology in the years to come. Biological research is one of the key areas of deployment for Laserglow's laboratory lasers, and we are proud suppliers to many leading space research centers around the world.
1. 'Inflight Biological Sample Preservation and Analysis' - Small Business Innovation & Research: Online Link-NASA
4. 'Sequencing DNA in the palm of your hand' - NASA Article on Phys.org Sept 30, 2015: Online Link-Phys.org
Measuring Effectiveness of Human Stem-Cell Transplants Using Optogenetics
Researchers at Stanford University have proposed a multi-disciplinary method that measures the health of neuronal circuits following surgery, when stem-cell derived neural transplants have been used. The study is built on the principles of optogenetics, stem-cell biology and neuroimaging performed with functional magnetic resonance imaging - fMRI - technology and aims to assess the effectiveness of the surgery on host circuitry in-vivo. Laserglow's LRS-0594 laser was used as an illumination source in the experimental setup.
Despite the potential of stem-cell derived transplants in treating intractable neurological diseases, it has been difficult for neuroscientists to effectively measure performance of the transplanted neurons within the host, as the overall effects on the central nervous system are hard to map. The researchers propose that by engineering stem-cells to express channelrhodopsin-2 and noting the effect of optogenetic stimulation using fMRI, it's possible to overcome this problem and hence optimize transplant therapy. While previous methods focused on anatomical or behavioral outcomes, this technology directly measures the ability of engrafted cells to modulate downstream circuits, and allows these functional connections to be visualized across the whole brain of an intact subject. The researchers believe that the reconstruction of the neural circuitry is what makes this technique uniquely promising for optimizing treatment for Parkinson's disease, Alzheimer's disease, multiple sclerosis and retinal degenerative disease.
The study was presented in Feb 2015 and first published in April in Science Direct- Neuroscience. To learn more about the experimental setup, methodology and detailed results, go to:
Stanford Full Paper
Laser-Based Eye Test Detects Early Onset of Alzheimer's
An innovative and cost-effective way of detecting Alzheimer's has been proposed by Cognoptix and aims to change the way patients are identified and treated. The test is broadly based on detecting the levels of beta-amyloid- a hallmark of Alzheimer's disease (AD) - in the lens of the eye. A breakthrough discovery indicates that growth in the eye parallels the growth of beta-amyloid in the brain. While current diagnosis methods are invasive, expensive and time-consuming, this proposed test aims to non-invasively and quickly aid diagnosis of AD.
Cognoptix's SAPPHIRE II system is a drug/device combination for early AD pathology detection. An ophthalmic ointment containing an amyloid-binding ligand is administered to the inner eyelid. The lens of the eye is then scanned with a low-power laser. This causes the ligand/amyloid complex to fluoresce. The fluorescing ligand molecule emits light at a different wavelength based on Stokes-shift effect. The systems measures the fluorescence data to determine how much amyloid there is in the eye. The actual test takes less than 5 minutes, has no toxicity issues, is easy to use and has no requirement for blood-draw or other invasive monitoring.
With promising early clinical results, the company hopes that neurologists will be the first early adapters of this technique, followed soon after by ophthalmologists and other specialists. Read more at:
BioOpticsWorld full article