Update on Cosmic Kiss project “Touching Surfaces”: Developing a tool for interdisciplinary health and space habitat research

Abstract

The human skin is inhabited by a diverse community of microorganisms, which play an important role in maintaining health and integrity of the skin itself. While the environment affects the human microbiome, the human microbiome also affects its environment. Besides beneficial microorganisms, also opportunistic pathogens reside on the skin, which can be spread to our environment. Hereby, especially frequently touched surfaces can pose as a reservoir for potentially pathogenic microorganisms. Additionally, microorganisms can compromise functionality of onboard systems. Hence, consideration and evaluation of microbial dispersal, growth and adaptation of microorganisms to monitor and prevent microbial contamination of harmful bacteria is crucial, especially in the context of space travel. One promising approach to reducing microbial contamination is the use of antimicrobial surfaces. In “Touching Surfaces” novel copper-based antimicrobial surfaces were tested under real space conditions on the ISS, in schools, and in clinical settings. Touching Surfaces was part of the Cosmic Kiss mission of ESA astronaut Matthias Maurer and tested onboard the ISS. The hardware of Touching Surfaces -so-called Touch Arrays- was designed for application-based testing and allows easy implementation and testing of different surfaces. One key objective of Touching Surfaces is the evaluation of antimicrobial surfaces to reduce microbial contamination on the ISS. Five Touch Arrays were installed on the ISS and touched from September 2021 to March 2022 by ESA astronauts Matthias Maurer and Thomas Pesquet. Upon return to Earth, the Touch Arrays were analyzed regarding their microbial community and material integrity to determine antimicrobial efficiency, which be then related to the environmental conditions on the ISS. Touch Arrays represent an easily implementable tool for future interdisciplinary health and space habitat research. Using application-based strategies for testing antimicrobial surfaces will help gain deeper understanding of underlying interactions of surface and microorganisms, as well as design of antimicrobial contact surfaces.