Effects of peritoneal lavage fluid from radiation or/and burn injured rats on the growth of hematopoietic progenitor cells

Abstract

Purpose: To evaluate the effects of peritoneal lavage fluids from radiation injury, burn injury and combined radiation-burn injury on the growth of hematopoietic progenitor cells (HPC).Materials and methods: Rats were divided into four groups: A radiation group (RG), a burn group (BG), a combined radiation-burn group (CRBG) and normal control group (NG). RG and CRBG rats were irradiated with 12 Gy, and burns of 30% total body surface area were generated in group BG and group CRBG. Peritoneal lavage fluids were collected and tested for their effects on the growth of erythrocyte progenitor cells or granulocyte-macrophage progenitor cells of BALB/c mice in vitro.Results: The numbers of colony forming units-erythroid (CFU-E), burst forming units-erythroid (BFU-E) and colony-forming units-granulocyte-macrophage (CFU-GM) formed after treatment with lavage fluids from BG or CRBG were significantly higher than those from NG. However, fewer CFU-E, BFU-E or CFU-GM colonies were found after treatment with lavage fluid from the RG. In lavage fluid from BG and CRBG, the concentration of interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor α (TNFα) was increased in comparison to NG and RG. Treatment with these cytokines had similar promoting effects on the growth of hematopoietic colonies and neutralizing antibodies inhibited these effects significantly.Conclusions: Burns increase the responsiveness of the system and help the proliferation of hematipoietic progenitor cells, while radiation decreases all these responses relative to both the controls and the burn plus radiation group.