The Antibody V(D)J Recombination Machinery in Normal and Altered Gravity (Amphibody)
Research Area: Cellular Biology
Expedition(s): 13
Principal Investigator(s): ● Jean-Pol Frippiat, Lorraine University, Nancy, France
RESEARCH OBJECTIVES
The Antibody V(D)J Recombination Machinery in Normal and Altered Gravity (Amphibody)
experiment studies whether antibody synthesis is affected when animal development occurs on
the International Space Station (ISS) and, if so, which spaceflight-associated environmental
modification has the greatest impact on antibody synthesis. Embryos of the amphibian Pleurodeles
waltl are allowed to develop during 10 days of spaceflight in Mini-Aquaria, either in weightlessness
or on a 1 g control centrifuge. Tissue samples are collected either immediately on return or 25
days postflight for analysis.
RESULTS
This experiment revealed that Immunolglobin M (IgM) heavy-chain transcription was doubled at
landing. To determine which space-related environmental modification was responsible for this
change, environmental modifications encountered by embryos during their development on the
ISS were recreated on ground. This approach demonstrated the fact that gravity changed during
Pleurodeles waltl development, and induced a change in IgM heavy-chain transcription.
Moreover, this change was associated with variations in nuclear factor kappa-light-chain-enhancer
of activated β cells (NF-κβ) mRNA levels, which play a key role in regulating immune response.
Given that P. waltl larvae were not immunized during the mission, data suggested that an
alteration of B lymphocyte generation could occur if gravity is modified during P. waltl
development.
The amounts of transcripts encoding NF-κβ molecules were increased in P. waltl embryos that
developed at 3 g and were decreased in those that developed under simulated microgravity, as
was shown in human T cells. Important immunological information can be deduced from space
experiments performed with an amphibian species.
Finally, it can be shown that an immature vestibular system is transiently sensitive to microgravity
exposure and that its exposure to hypergravity leads to a slowly growing vestibular sensitization.
PUBLICATION(S)
Frippiat J, Contribution of the urodele amphibian Pleurodeles waltl to the analysis of
spaceflight-associated immune system deregulation. Molecular Immunology. December
2013;56(4):434-441. doi: 10.1016/j.molimm.2013.06.011.