Current Development And Future Of Space Biotechnology

Space biotechnology is a promising field which is growing at a fast pace for the advancement of space exploration using tools of biotechnology. Since the installment of the International Space Station ISS back in 1998, many laboratory components have been built to carry out experiments in microgravity. Using microgravity and technologies for space environment, new products of biotechnology are now being made. There are, however, some technical and scientific challenges that need to be overcome in order to efficiently apply the biotechnology tools in space. The environment away from the earth is hostile to terrestrial organisms as they are subjected to several stress factors. Such factors include reduced gravity, low pressure, high amounts of UV radiation, variations in temperature, derivation of nutrition and dehydration. In order to survive in space, all the stress factors must be dealt with collectively. Counteracting the detrimental effects of these stress factors can ensure long term safe exploration of space.

Experiments done in the early 60s unraveled that microgravity has significant effects on living organisms. When biological samples were investigated in space environment, it was found that the diminishing gravitational force changed the biological functions of the cells. One such change is the disorganization of the cellular architecture due to changes in cytoskeletal elements. This effects the cell signaling and cell cycling. Endothelial cells are susceptible to gravitational stress and it leads to changes in the expression of inflammatory mediators. Changes in cytoskeleton collectively causes changes in arterial geometry and stiffness. This leads to cardiovascular deconditioning by astronauts. Such investigations have lead to the application of P2-receptor ligands as drugs and it can help astronauts during spaceflight. By exposing cells to different conditions, unique insight can be gained about how they react to their environment. Research focused on microgravity can increase our knowledge on cell physiology and that in turn can be used to facilitate space studies. Microgravity also poses the risk of traumatic injury and causes slow wound healing. Apart from that, astronauts may become immune compromised, face light levels of bacteria growth that are antibiotic resistant, and experience a reduction of bone density and loss of muscle. Bone density reduction, in particular, is a serious problem faced by astronauts who remain in space for a long period of time. Due to a lack of weight related activates there is a rapid change in bone metabolism which leads to bone loss. Regulatory pathways are investigated in order to find targets for therapeutic interposition.

Currently, there are technological limitations on the level of medical expertise onboard for space travel. It is very difficult to operate in space conditions. Then there are the added problems of not having enough water, volume, and other supplies. The aseptic techniques need adjusting to, along with the proper removal of hazardous chemicals. When an astronaut sustains any injury or gets sick, it takes a while before they can get medical care, especially if they are on a lunar base. Sometimes, the patient cannot withstand the shock from landing, or is non-transportable. Medical evacuation in such conditions require a huge sum of money, roughly more than 250 million dollars. Correct management of injuries in microgravity environment can thus minimize the cost of space travel and allow longer trips to space. Such a feat can be possible with techniques of biotechnology. The adverse effects caused by microgravity are studied in animal models such as rats and mice. These animals mimic the responses of humans to the effects. A study was conducted on the ISS to observe the consequences that long-term microgravity exposure had on mice. Real time-quantitative polymerase chain reaction (RT-qPCR) was used for the analysis of gene expression. The study helped in the identification of molecules that could be targeted for developing countermeasures. Investigations based on RT-PCR of mice flown for 13-day mission on the space shuttle showed an increased risk of cancer, tissue injury, infection, and pathologies.

Another study was done on the fruit fly, Drosophila, to see how the immune system is affected by spaceflight. Fruit flies are ideal candidates for such studies as they share pathways with the innate immunity system of humans. After exposing the fruit flies to 12 days of microgravity, the changes in gene expression was measured. The study showed that humoral and cellular immune response got altered due to spaceflight. A study conducted in late 90s explored tissue engineering using cartilage in space. It was the longest experiment on cell culture that had been done in space during that time. Three-dimensional engineering technology was used to grow cartilage on earth for three months and Mir Space Station for four months. This was compared to cells grown on earth for the same period of time. The objective was to evaluate the effects of space environment on the cells. Biotechnology System (BTS) was used to cultivate the cells. The viability of the cells was measured using Molecular Probes. The constructs that were grown on Mir were inferior in terms of mechanical properties and smaller than the constructs grown on earth. Studies such as these can help understand the effect of microgravity on different types of cells. Since then, tissue engineering of different parts such as bone, liver, and pancreas has been done in microgravity. This has also lead to the development of 3D tissue models.

Activities of biotechnology in microgravity conditions started since early 1970s. The research encompassed several areas such as bioreactor design, bioseperation, microencapsulation and protein crystallization. The main separating techniques studied under microgravity are electrophoresis and two-phase partitioning based on thermodynamics. Protein crystallization is an important field of research as protein structure knowledge can enable the design of immunosuppressive agents and other drugs. Protein crystals grown on space are larger and are of better quality than the ones grown on earth. A team from Japan at the Osaka Bioscience Institute observed 3D structures of a muscle protein grown in space and compared them to the crystals grown on earth. The crystals grown on space gave better X-ray diffraction patterns.

Another important area of research is microencapsulation, a technique used for immobilization of biological materials. Microencapsulation can prevent physical stress caused by sheer force when animal cells are placed in bioreactors and can aid in artificial organ development. Designing space bioreactors are essential for effective bioprocessing of products in space. Since March 2015, the International Space Station has enabled 1900 microgravity experiments to be conducted by 2700 researchers around the globe. New developments in space-based techniques allowed the production of three dimensional cell cultures that mimic the interactions between cells. This helped in advanced studies of tumor formation and pathogenesis. Studies relating to cancer initiation is of great importance to spaceflight because long duration space travel increases the risk of radiation exposure. Analysis based on microarrays revealed the proteins and genes that are involved in cancer regulation in simulated microgravity conditions. This created new possibly in finding new targets for cancer treatment. In fact, with the help of mass spectroscopy, an important regulator of thyroid cancer in microgravity conditions has already been identified.

Microbial communities coexist in the space environment with humans. They can be introduced to the space environment to facilitate further exploration. Microbial communities can be engineered for processing waste and for biofuels. They can also facilitate the production of oxygen, water, nutrients and other vital resources by converting the waste produced during space exploration. European Space Agency created a project called Micro Ecological Life Support System Alternative (MELiSSA) to create a bio-regenerative system which serves this purpose. Biological systems can also be engineered for mining and fuel production. For instance, they can produce rocket fuel, and adhesive materials to support activities on the lunar surface. In addition to that, several studies have concluded that they can be used to produce food on the moon which would be both safe and economically feasible. For instance, methanotrophs are food sources that are nutritionally complete and use methane for growth. Using the techniques of biotechnology, it is possible to genetically engineer methanotrophs for the production of any biotechnology products. They require no carbon source, and can grow rapidly in a small space allowing the production of diverse range of products in space.

Providing fresh source of food to crew members is vital for long space flights. It is also essential for future establishment of extraterrestrial self-sustaining colonies. One part of research by ISS is to understand the growth of flowering plants in microgravity. In 2014, NASA created a facility called Veggie for the production of vegetables and installed it in the space station. The facility is capable of producing higher plants and crops. The first crop to grow in Veggie was the red romaine lettuce which was later consumed by the crew members. Next, they grew zinnia flower because it was more difficult to grow. It gave an idea about how to grow important crops like tomato. The nutrients and light source provided by Veggie came from a growth chamber which is low of cost. Thus, fresh food can be produced for both as a food source and recreation during long-duration space travels. Understanding the environmental limit of our existence is substantial for assessing life on and beyond earth. Microorganisms are subjected to extra-terrestrial conditions in order to study their biological responses.

Facilities such as EXPOSE and BIOPAN have been developed for such experiments. There is also a Mars chamber, a simulation facility for conducting experiments. So far, the simulation facility has enabled the identification of environmental factors necessary for survival on Mars. Bacillus spores were used for a hypothetical mission, in EXPOSE facility, to Mars. The hardiness of the spores was assessed for 1. 5 years and the study showed that the extra-terrestrial UV radiation was a major limiting factor for growth. There is potential in high-throughput instruments in advancing research in space biotechnology. Phylogenetic microarrays, such as PhyloChip, can detect the ribosomal RNA of different types of species. They can be useful in space for environment monitoring. The PhyloChip currently is capable of detecting 50, 000 bacterial and archeal species. So, it can be utilized in space for monitoring the bacteria population. Advanced version of the PhyloChip, known as Lawrence Livermore Microbial Detection Array (LLMDA) has been developed and sent to ISS to collect samples from different surfaces, including on astronauts and then return the samples back to earth. This helped characterize the bacterial and fungal community as well as the corresponding virulence factors. Another potential lies in the study of metabolites, or metabolomics. Using metabolomics, it is possible to characterize the biomarkers linked to spaceflight. Metabolic studies based on gut microbiota can help search for biomarkers that can improve nutrition.

NASA has taken a new initiative known as Wetlab-2. The purpose of this is to provide the ISS with a variety of biotechnology instrument that would allow sample analysis on orbit. An instrument called RAZOR EX was used on board the ISS. It uses PCR based mechanism for the detection of microorganisms. The technology is fast and very reliable. Currently it is being used for water sample validation as a part of Water Monitoring Suite. Another instrument called the Gene Expression Measurement Module (GEMM) has been built for measuring gene expression of reengineered microorganism on board small spacecrafts. A microarray based instrument, Sign Of Life Detector (SOLID), was built to detect biomarkers from extreme environments.

Lastly, the Search for Extra-Terrestrial Genomes (SETG) has been developed for detecting any DNA or RNA based life. The potential of space biotechnology is quite evident from the studies that have been done so far. Utilizing the microgravity laboratories in Space Stations will further enhance the knowledge on space travel, and with the use of high-throughput instruments, can help create advanced biotechnology products in space. It can also help minimize adverse effects of space on astronauts so that they can stay longer in space or can undertake longer space journeys in search of new discoveries. Further space exploration can help unlock more scientific potentials beyond our dreams. Apart from that, biotechnology techniques used in microgravity conditions can help in the study of human physiology, and give us more knowledge on wound healing and better medical treatment for space programs. With endless possibilities, space biotechnology can only lead towards cycles of more innovation and discovery.