Cryopreservation for Long-Term Space Flight

Techniques of cryopreservation have been extremely valuable in clinical medicine. Cryopreservation of fertilized ova, oocytes, and sperm has been a valuable addition to the medical approaches to infertility. Cryopreservation of hematopoietic stem cells from the bone marrow peripheral blood or umbilical cord blood has revolutionized the methodology and protocols for bone marrow transplantation to treat cancer. Cryopreservation of cell lines for research, including cancer cell lines and normal tissue cells from individual patients, has provided resources for improving the effects of therapeutic chemotherapy and radiation. However, cryopreservation has limitations and has uncovered the potential deleterious effects of the agents used to preserve cells providing an “antifreeze” methodology to facilitate not only the freezing, but the thawing of the cells. A major focus of current space-radiation research is whether cryopreserved cells sustain injury from space irradiation and how these potential injuries would influence the condition of cells, tissues, and organs after thawing. Given the limitations of human lifespan, and the potential for space travel missions that might exceed years or decades of human life required to complete the mission, cryopreservation of astronauts continues to be an area of research to perhaps yield a practical approach.