Counterbalancing immunosuppression-induced infections during long-term stay of humans in space

The immune system is reported to be highly sensitive to different stressors that exist during space flight. Immune system dysregulation during and immediately following space missions is extensively reported. Solar and galactic radiation are among the major environmental factors which increase the risk of infection during extended stays of humans outside the Earth’s magnetic field. It has been reported that in addition to the effects on the host immune system, decreased antibiotic potency and enhanced microbial virulence are outcomes of long-term space flights. In long-time space missions, the probability of transformation of the neutral microorganisms into the harmful ones can pose a threat to astronauts’ health. In a widely cited publication, we suggested that for a deep space mission the adaptive response of all potential crew members be measured and only those with high adaptive response be chosen. We hypothesised that chronic exposure to elevated levels of radiation can considerably decrease radiation susceptibility of the selected astronauts and better protect astronauts against the unpredictable exposure to solar flares and coronal mass ejections. On the other hand, the results obtained in our recent studies indicate that exposure of laboratory animals to radiofrequency radiations emitted from a common mobile phone can induce a survival adaptive response as increased survival rate at a specific time after exposure to a pathogenic micro-organism. We recently indicated that pre-exposure of mice to radiofrequency radiations emitted from a GSM mobile phone (GSM, global system for mobile communications) increased their resistance to a subsequent Escherichia coli infection. The survival rates in 25 animals that received both adapting (radiofrequency) and challenge doses (bacteria) and the 20 animals that received only the challenge dose (bacteria) were 56% and 20%, respectively. In this light, our findings lead us to assume that this phenomenon can be used as a method for decreasing the risk of infection during deep space missions.