Effects of CD14 and TLR4 on LPS-mediated normal human skin fibroblast proliferation.

BACKGROUND

This study was designed to elucidate the effects of CD14 and TLR4 on the proliferation of LPS-mediated normal human skin fibroblasts and to gain new insights into the mechanisms underlying LPS-induced scar formation.

METHODS

Cell morphology and density were observed using an inverted microscope. Proliferation curves were described by MTT. The number of proliferating cells was counted by staining the cells with trypan blue. Cells were stained with propidium iodide (PI) and the phase of cell generation cycle was determined by flow cytometry.

RESULTS

The growth rate detected in groups B, C, D was slower compared to group A after 48 h. All proliferation curves were approximately S shaped and the peak was seen on days 6, followed by a sharp decline on days 7. The proliferation rate of groups B, C, D was significantly slower than group A. After the staining, we found a significantly smaller number of proliferating cells in groups B, C, D as compared to group A. Flow cytometry revealed that the ratio of proliferating cells at S phase was lower in the groups B, C, D as compared to group A.

CONCLUSIONS

Both separate and combined use of anti-CD14 and anti-TLR4 enable a significant decline in the rate and capacity of proliferation, with the latter pretreatment resulting in the sharpest reduction. Therefore, it seems likely that anti-CD14 along with anti-TLR4 is significantly engaged in the signaling mechanisms of LPS-mediated fibroblast proliferation.