ObjectiveTo investigate the effect of low intensity pulsed ultrasound（LIPUS）on the proliferation and anti-tumor effect of human peripheral blood lymphocytes（HPBL）.MethodsFicoll gradient centrifugation was used to separate HPBL.LIUPS of 0 intensity was set as the control group

and the stimulation group was 10 mW/cm

2

20 mW/cm

2

30 mW/cm

2

40 mW/cm

2

and 50 mW/cm

2

respectively

then HPBL proliferation was stimulated by stimulation groups for 10 min/d for two consecutive days.The proliferation activity of the cells was measured by the CCK-8 assay.The expressions of anti-tumor factors interferon-γ（INF-γ）

interleukin 2（IL-2）

tumor necrosis factor α（TNF-α）and granulocyte-macrophage colony stimulating factor（GM-CSF） in the supernatant of culture medium were detected by the ELISA assay. The anti-tumor activity was detected by co-culture of HPBL and human lung giant cell carcinoma cells（95 D）.ResultsAter 2 d stimuli

30 mW/cm

2

group significantly promoted HPBL proliferation compared with the control group and other stimulation groups after stimulated for two consecutive days（P

<

0.01）.The results of CCK-8 showed that the optical density of 30 mW/cm

2

group was significantly different from that of the control group

20 mW/cm

2

group

40 mW/cm

2

group and 50 mW/cm

2

group

respectively（P=0.032

0.027

0.027

0.001）.Anti-tumor factor detection showed that the levels of INF-γ

IL-2

TNF-αand GM-CSF in 30 mW/cm

2

group were（39.66±8.30）ng/L

（619.84±125.94）ρg/ml

（461.29±14.08）ng/L

（108.11±2.07）ng/L

respectively

which were higher than those in the control group[（24.40±6.84）ng/L

（279.56±128.18）ρg/ml

（417.17±21.44）ng/L and（96.53±1.56）ng/L]and 50 mW/cm

2

group[（16.52±0.87）ng/L

（141.00±93.71）ρg/ml

（171.96±9.46）ng/L

（72.56±8.95）ng/L]

and the differences were statistically significant（all P

<

0.01）.Co-culture experiment showed that the killing rate of 95 D cells in 30 mW/cm

2

group was 51.11%±5.21%

whichwassignificantlyhigherthanthatinthecontrolgroup（42.86%±0.55%）and 50 mW/cm

2

group（42.00%±3.67%）

there were significant（both P

<

0.05）.ConclusionThe proliferation activity and killing rate of HPBL were increased after LIPUS stimulation.