Salmonella enterica is a highly infectious pathogen in terrestrial environments. A recent study explored for the first Time the effect of the space environment on the process of bacterial infection of human cells and found that the microgravity environment not only suppressed the immunity of human cells, but also altered the genetic phenotype of the pathogen, resulting in a more infectious bacteria.
Human activities in the space environment are rapidly increasing, and soon, not only scientific research activities, but also some ordinary people who can afford the expenses can travel to the space environment, not to mention that people are also planning several projects like establishing research bases on the moon, trips to Mars, and other long time living in space.
Therefore it is important to understand the effects of the space environment on the daily health of the human body. In the terrestrial environment, Salmonella enterica infection is a common disease caused by unclean Food.
Meat that is not fully cooked, fruits and vegetables that are not treated well, drinking water, and spoiled food are all susceptible to this infection. According to the U.S. Centers for Disease Control (CDC), there are 1.35 million cases of food-triggered Salmonella enterica infections in the United States alone in a year, with 26,500 cases requiring hospitalization and 420 deaths due to ineffective treatment.
A study published March 9 in the Nature Publishing Group Journal – Microgravity (npj Microgravity) explores for the first time how this infection process differs from the terrestrial environment in the microgravity environment of space.
Cheryl Nickerson, a professor of applied microbiology at Arizona State University, one of the lead researchers, said some previous studies have cultured Salmonella in the space environment but then brought them back to the ground environment to study the infection of human cells.
This study, however, used the last few cargo missions before NASA’s space shuttle program came to an end to send some human intestinal epithelial cells inside the International Space Station (ISS). For the first time, their infection by Salmonella Typhimurium was observed in a space laboratory environment.
The researchers grouped these human cells, with some performing infection experiments and others not being infected as a comparison. It turned out that the transcriptome and proteome of genes within human epithelial cells were altered in microgravity, whether infected or not. Not only that, they found that even the transcriptome of bacteria was changed at the same time.
Human epithelial cells are an important line of defense for the body’s natural immune system. Jennifer Barrila, lead author of the study, said, “Before we started this study, we already had extensive data showing that the space environment completely changed Salmonella at all levels, making it more infectious. The space environment has been seen in other studies to weaken the ability of human cells to defend against the disease. However, there is no evidence yet that infection occurs when the two meet in a space environment and become infected. Our study suggests that intestinal epithelial cells appear more severe after being infected with Salmonella in a microgravity environment.”
Recent Comments