Here’s something you never realized you had to worry about: space germs. New research suggests that our immune system would have difficulty detecting and responding to germs from other planets.
Of course, this is all hypothetical. Your chances of coming into contact with an extraterrestrial microorganism in the near future are slim; Scientists have yet to gather any direct evidence of life outside of Earth. However, the research has some important implications for space missions and humanity’s bold plans to colonize other planets.
“The world is now too aware of the immune challenge posed by the emergence of new pathogens,” explained Professor Neil Gow, assistant vice chancellor (Research and Impact) at the University of Exeter. statement.
“As a thought experiment, we wonder what would happen if we were exposed to a microorganism that had been recovered from another planet or moon where life had evolved,” he added. “Could our immune system detect the proteins made from these non-terrestrial building blocks if such organisms were discovered and brought back to Earth and then accidentally escaped?
Reported in the newspaper Microorganisms, Scientists at the universities of Aberdeen and Exeter in the United Kingdom observed how mice, whose immunity cells They function in a similar way to those of humans, they respond to components that are probably found in the so-called exo-microorganisms from beyond the Earth.
The researchers examined the reaction of T cells, major immune system soldiers, to amino acid-containing peptides, such as isovaline and α-aminoisobutyric acid. These amino acids have been found in great abundance in meteorites, but they are extremely rare in the tissues of organisms on Earth, so the researchers argue that these would be a good indicator to understand how the body of a mammal could react to microorganisms. strangers.
The immune response seemed to be noticeably weaker for exopeptides. Although T cells were still activated by exopeptides, their response was less efficient compared to their reaction to more typical Earth-bound peptides. Activation levels of 15 percent and 61 percent were observed against isovaline and α-aminoisobutyric acid, compared to activation levels of 82 percent and 91 percent when exposed to peptides made entirely of amino acids that are common on Earth. .
“Our research showed that these exopeptides were still being processed and T cells were still activated, but these responses were less efficient than for ‘ordinary’ Earth peptides,” added Dr. Katja Schaefer, lead author at the University of Exeter .
“Therefore, we speculate that contact with extraterrestrial microorganisms could pose an immunological risk to space missions aimed at recovering organisms from exoplanets and moons.”
As Professor Gow mentioned, the past few months have made it clear how dangerous a new pathogen can be, but be without illusion: the coronavirus responsible for Covid-19 did not come to Earth in a meteorite (as some British tabloids have suggested).
“The most compelling evidence that SARS-CoV-2 does not come from a meteorite is that it is so closely related to other known coronaviruses,” said Dr. Dominic Sparkes, an infectious disease specialist. IFLScience in February. “It is closely related to the SARS virus (severe acute respiratory syndrome) that caused an outbreak in the early 2000s and the MERS (Middle East respiratory syndrome) virus that still causes the disease today.”
