Influence of conditioned medium pretreatment on marrow recovery in sublethally irradiated mice.

Intraperitoneal administration of medium conditioned by thymocytes (TCCM) 18 h before whole-body irradiation with a single sublethal dose of 5.8 Gy stimulates haemopoiesis recovery in mouse bone marrow. Cellularity of femoral bone marrow in animals treated with TCCM was greater by 20-60% within 10-30 days after irradiation than that in mice only irradiated. CFU-S number was 1.5 to 2-fold higher at the same period. Histological examination showed a considerably higher rate of myelopoiesis recovery in bone marrow.