title: Effects of serum from rats with combined radiation-burn injury on the growth of hematopoietic progenitor cells.
abstract: BACKGROUND
  This study aims to observe the effects of blood serum from rats with radiation injury, burn injury, and combined radiation-burn injury on the growth of hematopoietic progenitor cells and to explore the possible mechanisms.
  
  
  METHODS
  Serum from rats with radiation injury, burn injury, and combined radiation-burn injury were collected at 3 hours, 12 hours, 24 hours, 48 hours, 72 hours, and 96 hours after injury and then was added to the culture medium to see its effect on the growth of hematopoietic progenitor cells (HPCs) at a final protein concentration of 10 microg/mL. Radioimmunoassay and enzyme-linked immunosorbent assay were employed to measure the level of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 in each group, and the effect of TNF-alpha and IL-6 on the growth of HPC was also observed.
  
  
  RESULTS
  The number of HPCs colonies formed after addition of the serum from rats with burn or combined radiation-burn injuries was significantly higher than that from normal rats at 3 hours, 12 hours, 24 hours, 48 hours, 72 hours, and 96 hours after injury and reached its peak value at 24 hours after injury. However, fewer HPCs colonies were found after the addition of the serum from irradiated rats. At the same time, the levels of TNF-alpha and IL-6 in the serum of burn group and combined radiation-burn injury group were significantly higher than that of normal group, and much higher than that of the irradiation injury group (p < 0.01). Also, TNF-alpha and IL-6 demonstrated promoting effect on the growth of HPC.
  
  
  CONCLUSIONS
  Serum from rats with burn injury and combined radiation-burn injury stimulates the growth of HPCs, while serum from irradiated rats shows inhibitory effects on the growth of HPCs. These effects may lie in the different level of TNF-alpha and IL-6 in the serum of each group.
authors.affiliation: Institute of Combined Injury, State Key Laboratory of Trauma, Burns and Combined Injury, College of Preventive Medicine, Third Military Medical University, Chongqing, China. ranxize@yahoo.com.cn
authors.forename: Xin-Ze
authors.initials: XZ
authors.lastname: Ran
authors.forename: Yong-Ping
authors.initials: YP
authors.lastname: Su
authors.forename: Zhao-Wen
authors.initials: ZW
authors.lastname: Zong
authors.forename: Chao-Hua
authors.initials: CH
authors.lastname: Guo
authors.forename: Huai-En
authors.initials: HE
authors.lastname: Zheng
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Chen
authors.forename: Guo-Ping
authors.initials: GP
authors.lastname: Ai
authors.forename: Tian-Min
authors.initials: TM
authors.lastname: Cheng
mesh_terms: D000818:Animals; D002056:Burns / Q000097:blood*; D049109:Cell Proliferation / Q000528:radiation effects; D002478:Cells, Cultured; D006412:Hematopoietic Stem Cells / Q000378:metabolism* / Q000528:radiation effects; D015850:Interleukin-6 / Q000097:blood / Q000528:radiation effects; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009104:Multiple Trauma / Q000097:blood*; D011832:Radiation Injuries / Q000097:blood*; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000528:radiation effects
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha