Mouse skin graft prolongation with donor-strain bone marrow and antilymphocyte serum. Effect of bone marrow cell...

Significant extended survival of C3H/He skin grafts in antilymphocyte serum (ALS)-treated B6AF1 mice can be brought about by the injection of donor-strain bone marrow on day 6 or 7 after grafting. In the present study, survival of the active graft-prolonging bone marrow cells under several storage conditions was investigated. The bone marrow cells retained their effectiveness if stored at 4 degrees C in 10% fetal calf serum for 18 hr prior to injection, but not if maintained at 37 degrees C under standard lymphocyte culture conditions. Freezing the cells for 10 days in a cryoprotective medium preserved the ability of the cells to prolong graft survival. In fact, freeze-thawed cells were more effective than fresh cells. Extension of the ALS-bone marrow treatment protocol to human transplantation is expected to be facilitated by frozen and short-term refrigerated storage of the donor bone marrow.