Sensitivity of porcine peripheral blood leukocytes to gamma irradiation in vivo, in vitro and ex vivo.
OBJECTIVE
The large white pig is a useful experimental model to compare in vivo, in vitro and ex vivo sensitivity of peripheral blood leukocytes to ionising radiation. Such studies are impossible to perform in humans and laboratory rodents due to ethical reasons and body size, respectively. We analysed dose- and time-dependent changes of lymphocyte and granulocyte absolute numbers in porcine peripheral blood after either whole-body irradiation (in vivo and ex vivo experiments) or exposure of porcine whole blood to γ-irradiation (in vitro experiments).


METHODS
CytoCount™ absolute counting beads and light scatter analysis using a flow cytometer were used to determine major leukocyte subpopulation numbers in blood samples after red cell removal.


RESULTS
Similar to other species, lymphocyte numbers significantly decreased in pigs both in vivo and in vitro in a dose-dependent manner. Most importantly, our data clearly show that reduction of lymphocyte numbers after irradiation in vivo proceeds much faster than after irradiation in vitro and that granulocyte changes depend only on the time of analysis after irradiation.


CONCLUSIONS
All three tested experimental arrangements demonstrated the radiosensitivity of lymphocytes and the radioresistance of peripheral blood granulocytes. These in vivo and in vitro approaches, as well as the newly introduced ex vivo observations, appear to be relevant to biodosimetry.
Department of Radiobiology, Faculty of Military Health Sciences, University of Defence, Trebesska, Czech Republic. zarybnicka@pmfhk.cz
Lenka
L
Zarybnicka
Zuzana
Z
Sinkorova
Jiri
J
Sinkora
Vaclav
V
Blaha
Jirina
J
Vavrova
Jaroslav
J
Pejchal
Jan
J
Osterreicher
D000818:Animals; D002452:Cell Count / Q000379:methods*; D004307:Dose-Response Relationship, Radiation; D005434:Flow Cytometry / Q000379:methods; D005720:Gamma Rays; D066298:In Vitro Techniques; D007962:Leukocytes / Q000166:cytology* / Q000528:radiation effects*; D008027:Light; D011836:Radiation Tolerance; D011839:Radiation, Ionizing; D012542:Scattering, Radiation; D013552:Swine; D014916:Whole-Body Irradiation