[Effects of serum from normal and burned rats on the biological behavior of bone marrow stromal cells]

To investigate the effect of serum from normal and burned rats on the biological behaviors of bone marrow stromal cells (BMSCs).

Bone marrow was extracted from sacrificed Wistar rats and BMSCs were then incubated in F-12 medium in the presence of fetal calf serum (FCS, group F), normal rat serum (group N), serum harvested from burned rats at 3 days (group B1) and 14 days (group B2) after burn injury. The growth curve, cell cycle, apoptosis rate and contents of DNA of BMSCs were investigated.

The growth curves of cells incubated in different rat serum were similar, but were significantly different from that of cells incubated in FCS. The doubling time of cells incubated in rat serum from group N, B1 and B2 were 23.7, 18.6 and 20.2 hours, respectively, which were significantly shortened compared with that in group F. Compared with group F, the numbers of cells at platform phase in group N, B1 and B2 were greater. The ratios of cells at phase G0/G1 in group B1 and B2 were significantly lower than those in other groups (all P<0.01), but the ratios of cells at phase S were adverse (P<0.01). Contents of DNA in cells incubated in rat serum were greater than that in cells incubated in FCS (P<0.05 or P<0.01). Contents of DNA in cells incubated in serum from burned rats were greater than that in cells in normal rat serum (P<0.01). The rate of cell apoptosis in group B1 was higher than those in other groups (P<0.01).

Rat serum is more effective to stimulate proliferation of BMSCs from rat in vitro than FCS. There are probably many factors affecting the growth of BMSCs, the contents of which changed with the time after burn injury. The effects of serum from burned rats on the growth of BMSCs are complex.