Mechanism of PD‑1/PD‑L1 signaling pathway regulating Treg/Th17 in the occurrence and development of preeclampsia

Objective:To detect the expression levels of programmed cell death 1(PD‑1)and its ligand PD‑L1,regulatory cell(Treg)and T helper cell 17(Th17)specific nuclear transcription factors forkhead box protein 3(Foxp3)and the retinoic acid‑related orphan nuclear receptorgammat(RORγc)in the placenta of normal pregnant women and in preeclamptic(PE)women,and to study the relationship between their differential expression and the development of PE.Methods:Between March 2021 and March 2022,40 patients with pre‑eclampsia who were treated at the Obstetrical Department in Hainan Hospital were selected,including 20 cases of mild(PE)and 20 cases of severe(sPE),and 20 normal pregnant women with singleton cesarean section in the same period were selected to collect placental tissue.PD‑1,PD‑L1,Foxp3 and RORγc in placenta were detected by qRT‑PCR and Western blot.Results:(1)The results of qRT‑PCR assay showed that the mRNA expression of PD‑1,PD‑L1,Foxp3 protein decreased significantly compared with the control group.The changes in PD‑1,PD‑L1 and Foxp3 became more obvious as the disease progressed(P<0.05);The mRNA expression of RORγc increased significantly compared with the control group.The changes of RORγc mRNA became more obviousas as the disease progressed(P<0.05);(2)The results of Western blot assay show,compared with the normal group,the protein expression of PD‑1,PD‑L1,Foxp3 mRNA decreased significantly.With the aggravation of the disease,the changes of PD‑1 and PD‑L1 became more obvious,with significant difference(P<0.05);Compared with the normal group,the protein expression of RORγc increased significantly.With the aggravation of the disease,the changes of RORγc protein became more obvious with significant difference(P<0.05).Conclusion:PD‑1/PD‑Ll participates in the occurrence and development of preeclampsia by regulating Treg/Th17 immune balance.