A preliminary study of HL-60 cell DNA damage induced by thymopeptide from neonatal calf

Objective: To observe the effect of thymopeptide (TP,relative molecular mass less than 10 000) from neonatal calf on the growth of HL-60 cells and to explore the possible mechanism in this procession.Methods:HL-60 cells were cultured in the absence of or presence of TP at concentrations of 20 μg/ml and 40 μg/ml,respectively. Cell growth was examined with Trypan blue and cell growth curve was drawn. Single cell gel electrophoresis (SCGE) was used to detect the possible DNA damage of HL-60 cells. Agarose gel electrophoresis was used to observe the possible DNA-ladder of HL-60 cells.Results: The growth of HL-60 cell was inhibited 72 hours after cultured with TP(both 20μg/ml and 40μg/ml final concentration). There were more comet cells among HL-60 cells after TP culture than that before. Agarose gel electrophoresis results showed a 200 bp difference DNA-ladder after TP culture. Conclusion:TP can inhibit the growth of HL-60 cells through an apoptosis pathway of DNA damage.