Serial changes in two immune checkpoint receptors and ligands, Tim-3/Gal-9 and PD-1/PD-L1 in peripheral blood prior to miscarriage: Comparison with pregnancies resulting in a live birth

A significant and sustained increase in the proportion of Tim-3+ pNK cells was observed in pregnancies resulting in a live birth but not in pregnancies resulting in a miscarriage, suggesting the changes may be associated with successful pregnancy outcomes.

In pregnancies that resulted in a live birth, a significant and sustained increase in the proportion of Tim-3+ pNK cells was observed from the 9th to 30th days after ET, whilst the concentration of serum PD-L1 was significantly increased on the 23rd and 30th days after ET when compared to the day of ET. In pregnancies that later miscarried, none of the parameters were significantly changed across all the time points examined. When comparing the results between the two groups, the proportion of Tim-3+ CD56dim NK cells in the women who had a live birth was significantly higher than that in women who miscarried from the 9th to 30th day after ET.