ABSTRACT
Objective To study the radioprotective potential of CBLB502 protein against hemopoiesis injury by irradiat-ion. Methods C57BL/6J mice were assigned to normal irradiation, and CBLB502 0.2mg/kg 30min pre-irradiation group at random before 6.5 Gy 60Co-γray total body irradiation (TBI). The peripheral blood was obtained to assay hemogram pre and post-irradiation. The bone marrow nucleated cell counts were evaluated in mice at 2 h and 24 h after irradiation. Colony-forming unit (CFU) assay was used to analyze the alteration of hemopoietic progenitor cells in bone marrow. Competitive repopulation assay was conducted to observe the implantation ability of bone marrow cells. The percentage of each lineage hemopoietic cells was measured by flow cytometry analysis. Results CBLB502 significantly alleviated the sharp decrease of peripheral blood counts including leukocyte (WBC), erythrocyte (RBC), and platelet, and accelerated recovery. Counts of various hematopoietic progenitor cell colonies of mouse bone marrow in CBLB502 group were significant higher than those of irradiation group (P<0.01). CBLB502 significantly improved the implantation ability of bone marrow cells. Conclusion CBLB502 showed obvious radioprotective effects on haemopoiesis injury by irradiation.