Increased endothelial cell growth in culture supplemented with outdated human platelet lysate

The potency of Human Platelet Lysate (hPL) as an animal serum replacement in cell culture has been reported. The effect of outdated hPL derived from platelets that are stored beyond its expiry date is currently unknown. The study aimed to evaluate whether the outdated hPL retain its capacity as an animal-free based serum replacement in endothelial cell culture medium. Human Umbilical Vein Endothelial Cells (HUVECs) were cultured with basal medium of M200 supplemented with fresh hPL (5 days), outdated hPL (10 days) or FBS as control group. Cell proliferation, total protein and angiogenesis associated genes and total protein was compared. HUVECs proliferation and total HUVECs protein concentration was higher in hPL groups compared to those with FBS (p < 0.05). The highest total protein concentration was seen in hPL fresh group (p < 0.0001). Total protein and mRNA expression of endothelial markers tested in outdated hPL group were comparable to fresh hPL or FBS. The present study showed outdated hPL stimulated higher HUVECs proliferation than fresh hPL and control FBS. Outdated hPL affected HUVECs protein profile while genes associated with angiogenesis remained unaffected by hPL supplement. This implies platelet that has reach its expiry date could still be used for HUVECs culture, thus reducing the blood product waste that otherwise be discarded.