title: Characterizing responses to gamma radiation by a highly clonogenic fish brain endothelial cell line.
abstract: The clonogenic property and radiobiological responses of a fish brain endothelial cell line, eelB, derived from the American eel were studied.
  
  
  
  Clonogenic assays were performed to determine the plating efficiency of the eelB cells and to evaluate the clonogenic survival fractions after direct irradiation to low-dose low-LET gamma radiation or receiving irradiated cell conditioned medium in the bystander effect experiments.
  
  
  
  eelB had the second highest plating efficiency ever reported to date for fish cell lines. Large eelB macroscopic colonies could be formed in a short period of time and were easy to identify and count. Unlike with other fish clonogenic cell lines, which had a relatively slow proliferation profile, clonogenic assays with the eelB cells could be completed as early as 12 days in culture. After direct irradiation with gamma rays at low doses ranging from 0.1Gy to 5Gy, the dose-clonogenic survival curve of the eelB cell line showed a linear trend and did not develop a shoulder region. A classical radio-adaptive response was not induced with the clonogenic survival endpoint when the priming dose (0.1 or 0.5Gy) was delivered 6h before the challenge dose (3 or 5Gy). However, a radio-adaptive response was observed in progeny cells that survived 5Gy and developed lethal mutations. eelB appeared to lack the ability to produce damaging radiation-induced bystander signals on both eelB and HaCaT recipient cells.
  
  
  
  eelB cell line could be a very useful cell model in the study of radiation impacts on the aquatic health.
authors.affiliation: Radiation Sciences Program, School of Graduate and Postdoctoral Studies, McMaster University, Hamilton, ON, Canada. Electronic address: von1@mcmaster.ca.
authors.forename: Nguyen T K
authors.initials: NTK
authors.lastname: Vo
authors.affiliation: Radiation Sciences Program, School of Graduate and Postdoctoral Studies, McMaster University, Hamilton, ON, Canada.
authors.forename: Bibi S H
authors.initials: BSH
authors.lastname: Sokeechand
authors.affiliation: Department of Biology, McMaster University, Hamilton, ON, Canada.
authors.forename: Colin B
authors.initials: CB
authors.lastname: Seymour
authors.affiliation: Department of Biology, McMaster University, Hamilton, ON, Canada.
authors.forename: Carmel E
authors.initials: CE
authors.lastname: Mothersill
mesh_terms: D000811:Anguilla; D000818:Animals; D001921:Brain / Q000528:radiation effects*; D024201:Bystander Effect; D002460:Cell Line; D004307:Dose-Response Relationship, Radiation; D042783:Endothelial Cells / Q000528:radiation effects*; D005720:Gamma Rays / Q000009:adverse effects*; D042822:Genomic Instability / Q000528:radiation effects; D009154:Mutation / Q000528:radiation effects
keywords: Clonogenic cell line; Direct and non-targeted effects; Fish cells; Low-dose gamma radiation