Cosmos: 1989 immunology studies

The effects of flight on Cosmos mission 2044 on leukocyte subset distribution and the sensitivity of bone marrow cells to colony stimulating factor-GM were determined. A parallel study with antiorthostatic suspension was also carried out. The study involved repetition and expansion of studies performed on Cosmos 1887. Spleen and bone marrow cells were obtained from flown, vivarium control, synchronous control, and suspended rats. The cells were stained with a series of monoclonal antibodies directed against rat leukocyte cell surface antigens. Control cells were stained with a monoclonal antibody directed against an irrelevant species or were unstained. Cells were then analyzed for fluorescence using a FACSCAN flow cytometer. Bone marrow cells were placed in culture with GM-CSF in McCoy's 5a medium and incubated for 5 days. Cultures were then evaluated for the number of colonies of 50 cells or greater.