[Proliferative effect of low energy laser and colony stimulating factor on human umbilical cord blood hematopoietic cells].

OBJECTIVE

To study the proliferative effect of low energy laser on human cord blood hematopoietic cells in vitro and the relationship between the effect of low energy laser and colony stimulating factor (CSF).

METHODS

Human umbilical cord blood hematopoietic cells were irradiated with copper vapour laser and cultured in vitro. The number of colony and cells was calculated.

RESULTS

Laser irradiation synergized with CSF in expansion of cord blood hematopoietic cell. The GM-CFUc number from the group treated with irradiation plus CSF increased significantly as compared with that from other groups including laser irradiation or CSF treatment alone or control (P < 0.01). Reincubation of cord blood cells in the soft agar medium revealed that secondary colonies were formed and the absolute number of colony was obviously increased as compared with that before liquid culture. The number of colony in irradiation group was more than these of non-irradiation group.

CONCLUSION

Low energy laser irradiation for cord blood stem cells is effective in vitro expansion of cord blood stem cells.