Objective To study the effect of
heavy ion radiation on proliferation and
apoptosis of
human peripheral
blood derived
T lymphocytes and the mechanism .
Methods T lymphocytes were isolated from heparinized whole
blood samples by
density gradient centrifugation using
Ficoll before being irradiated with
heavy ion beams 12 C.The accumulated absorbed
dose (
dose-rate values=0.5 Gy/min, and meanLET=29 keV/μm).12 h and 24 h post-
infection, total
RNA of
T lymphocytes was isolated , and the
apoptosis related
gene expression , including Bcl-2, Bax, Caspase3, Caspase8 and Caspase9, was detected by RT-RT-PCR.24 h and 48 h after irradiation, the proliferation was analyzed by CCK 8 kit.The
cell apoptosis was detected by
flow cytometry after being labeled with AnnexinV-PE/7-AAD or AnnexinV-
FITC/PE.The expression of Bcl-2, Bax and Caspase3 was also assayed by RT-PCR.Results Data showed that
heavy ion radiation could inhibit the proliferation of
T lymphocytes obviously , and the inhibition ratio in
cells that received 2 Gy
dose was much high-er than in
cells that received 1 Gy
dose.Furthermore,
heavy ion radiation promoted the
apoptosis of
T lymphocytes signifi-cantly.The results of RT-PCR showed that the
mRNA expression of Bcl-2 was down-regulated in
heavy ion radiation T lym-phocytes while the expression of Bax and
Caspase 3 was up-regulated.Conclusion
Heavy ion radiation can inhibit the pro-liferation and promote the
apoptosis of
human peripheral
blood derived
T lymphocytes .