Oxygen and glucose dependent viability of HLA-G positive and negative trophoblasts using ACH-3P cells as first trimester trophoblast-derived cell model

Aims

During pregnancy HLA-G negative proliferative trophoblasts at the tips of anchoring villi form cell columns from which HLA-G positive extravillous trophoblasts invade maternal tissues. During the first trimester of pregnancy an oxygen gradient ranges from placental low to decidual high oxygen, which may have a differential impact on survival of the two trophoblast subpopulations. Moreover, diabetes-associated hyperglycemia may also influence trophoblast proliferation.

Methods

ACH-3P cells were separated by magnetic beads into HLA-G positive and negative cells and checked by PCR and Western blotting. Cell cultures were performed under varying oxygen and glucose concentrations. Numbers of viable and dead cells were assessed and used to calculate proliferation rates.

Results

After separation, HLA-G positive and negative first trimester trophoblast-derived ACH-3P cells exhibit fewer viable cells under hyperglycemia at 2.5% and 8% oxygen, while at 21% oxygen no viable cells were detectable. Cell numbers of HLA-G negative cells were higher compared to HLA-G positive cells at 2.5% and 8% oxygen, while there were significantly less cells at 8% compared to 2.5% only in HLA-G positive cells.

Conclusion

We conclude that the separated cell types are sensitive to both oxygen and glucose independent from each other. Furthermore, oxygen may be one regulator to reduce proliferation of invading HLA-G positive trophoblasts, while alterations in the oxygen gradient early in pregnancy may have deleterious effects on the number of invading extravillous trophoblasts.