OpNom: FITExperiment Overview
The Fungal Pathogenesis, Tumorigenesis, and Effects of Host Immunity in Space (FIT) experiment primarily studies the effects of spaceflight on the immune system responses of the fruit fly, Drosophila melanogaster. Since there is evidence that suggests the immune system of organisms are affected by spaceflight, this proposal seeks to assess the extent and the detailed molecular biological changes that are associated with spaceflight. In addition, this work also investigates the progression of cancerous and benign tumors in sensitized mutant lines (cells that turn into tumors) that show an increase in tumor formation, and is coupled with the effect of radiation exposure.Principal Investigator(s)
NASA Ames Research Center, Moffett Field, CA, United States
National Aeronautics and Space Administration (NASA)Sponsoring Organization
Human Exploration and Operations Mission Directorate (HEOMD)Research Benefits
Information PendingISS Expedition Duration
April 2006 - September 2006Expeditions Assigned
13Previous ISS Missions
This will be the first flight for the FIT experiment.
The Fungal Pathogenesis, Tumorigenesis, and Effects of Host Immunity in Space (FIT) investigation takes place on board the Space Shuttle during the STS-121/ULF1.1 mission. FIT addresses a series of health risks associated with space flight using Drosophila melanogaster (fruit flies) as a simple model organism that can be flown on the shuttle with minimal resources and with large samples sizes. The innate immunity is the first line of defense that multicellular organisms, such as humans and flies (Drosophila melanogaster), use when faced with pathogens. These responses include expression of antimicrobial peptides, phagocytosis of the microbes by blood cells and clotting/melanization. All of these responses will be measured from animals returning from space flight and compared to ground-bred animals. A fungal pathogen will also be flown in order to assess whether space flight results in changes in virulence in the fungus. Ground radiation studies with high energy protons, as experienced by astronauts during solar flares, will be used to assess the effects of radiation on the immune system as well as on tumor formation in the fly. The use of Drosophila melanogaster (fruit fly) to study immunity allows for large population sizes of animals to be studied in relatively small volumes, yielding statistically significant data.
It is a known fact that space travel affects the genetic activity of crewmembers, but researchers cannot yet predict which genes will be affected or precisely determine how gravity signals a gene to change. FIT is the first step in answering these questions.Earth Applications
Effects of pathogens on wild type and immune-compromised hosts is of great relevance to human immune diseases.
In flight, the crew conducts one session of the food tray change-out operation. At the time of the food tray change-out, the food tray exposed to the adult flies carries eggs, embryo, and larvae. The procedure consists of transferring a new food tray into the fly cassette that carries the adult flies and then transferring the food tray with the larvae into a new unused fly cassette. The Platform Kit is used to provide containment during this operation. Postflight, the specimens are returned for processing by the PI team.Operational Protocols
The flies are housed in cassettes that are modified from ESA type 1 containers and have been rebuilt at NASA Ames in order to ensure no escape of larvae, and for efficient food change-out in space using the Platform Kit also designed at NASA Ames for the FIT experiment.
FIT studied the effects of space flight on the immune system responses of the common fruit fly. Even short-term space flight affects the fundamental process of cellular and humoral (secretion of antimicrobial peptides into the blood and accessory processes) immunity and phagocytosis (the cell engulfing microorganisms) functions and the maturation of immune cells in Drosophila melanogaster (fruit fly) innate immune system (the first line of defense against invading microorganisms). Many of these changes mirror alterations seen in human innate immune systems postflight. The large number of fruit flies returned from FIT allowed a significant number of assays to be conducted postflight. Physiological changes observed in the innate immune system could be explained by gene expression changes, allowing a fundamental understanding of the underlying molecular pathways affected by space flight. (Marcu et al. 2011)
Marcu O, Lera MP, Sanchez ME, Levic E, Higgins LA, Shmygelska A, Fahlen TF, Nichol H, Bhattacharya S, Bhattacharya S. Innate Immune Responses of Drosophila melanogaster Are Altered by Spaceflight. PLOS ONE. 2011; 6(1): 1-10. DOI: 10.1371/journal.pone.0015361.