Restraint and sound stress reduce the in vitro migration of prethymic stem cells to thymus supernatant.

Murine bone marrow cells were examined in an in vitro assay to determine whether stress modulates the migration of prethymic stem cells to thymus supernatant. Adult CBA/J mice were either restraint or sound stressed for two hours daily for five days. Bone marrow cells were removed and migrated toward newborn thymus supernatant in an in vitro migration assay in blind well chambers. Bone marrow cells from animals which had been stressed for five days showed a significant decrease in the percent migration to thymus supernatant when compared to bone marrow cells from age-matched control mice. This suggests that either a smaller proportion of precursor cells are available in the bone marrow for migration to the thymus or the number of cells remains the same but these cells are less responsive to chemoattractive factors in the supernatant, thus causing them to migrate at a decreased rate.