Tiny experiments assessing impact of space on immune system, cancer and neurons sent to ISS
Image credit: DT
A series of smartphone-sized experiment containers carrying immune cells, neurons and cancer cells have been launched in a rocket to the International Space Station (ISS) in order to gain greater understanding of the impact of microgravity upon them.
The biological samples will remain in microgravity for 30 days and return to Earth in a Dragon capsule in mid-January 2018, when they will be examined in the laboratory.
The human immune system is weakened during prolonged stay in space. Preliminary tests on the ISS have shown that immune cell activity is affected by changes in gravity.
The cellular and molecular mechanisms responsible for this are still not fully known. Macrophages are the immune system’s front line of defence.
These scavenger cells, which are a type of white blood cell, are responsible for attacking and destroying bacteria and other pathogens in the human body.
Scientists suspect that the reason behind the immune system’s impairment is a disturbance of the cytoskeleton – the flexible inner framework structure of a cell – in the macrophages or a reduction in molecules on the cell surface.
The miniature experiment conducted by a team at the University of Magdeburg aims to record long-term changes in the macrophages caused by microgravity.
“Research under microgravity conditions over a prolonged period is only possible on the International Space Station,” project manager Michael Becker said.
“In the long term, the acquired knowledge will help develop countermeasures and drugs against immunodeficiency disorders. These will not only be helpful for astronauts on long-term missions in space, but also for patients on Earth.”
Thyroid cancer cells are the subject of the second experiment; previous studies have shown that in microgravity special cancer cells form a spherical group of tumour cells, called three-dimensional multi-cellular spheroids.
The effect of biochemical substances on spheroid growth, in particular, is best researched in microgravity, as gravitational forces are cancelled out under these conditions.
The biochemical substances will be analysed when the cells return. In addition to gene activation and deactivation, the main focus will be on investigating changes in all cell proteins to discover important signalling pathways. Knowledge of these molecular processes will help to develop tumour-fighting measures and specific cancer drugs.
For the third experiment, a team of scientists from the University of Hohenheim is exploring the effects of microgravity on neurons.
Preliminary investigations have shown that the cytoskeleton of neurons is impaired by changes in gravity. This cytoskeleton not only plays an important role in shaping the cell, but it also functions as an internal transport system for the exchange of information, such as communication between the neurons themselves.
The cytoskeleton is anchored in the cell membrane using special proteins and is jointly responsible for neuron excitability.
This ISS experiment focuses on these anchor proteins. Scientists want to investigate whether these proteins change or deform under microgravity and how the distribution of so-called channel proteins alters too.
These protein molecules are used to transport ions in the cells and are therefore also essential for neuron excitability. Scientists hope to gain knowledge regarding the development of neurons in microgravity, which is primarily relevant for astronauts on long-term missions in space.