Association between HLA-G 14bp Gene Polymorphism and Serum sHLA-G Protein Concentrations in Preeclamptic Patients and Normal Pregnant Women

ABSTRACT

Background: Preeclampsia (PE) is a multisystem syndrome that is a primary source of fetal–maternal morbidity and mortality. Human leukocyte antigen-G (HLA-G) is a nonclassical Major histocompatibility complex (MHC) class-Ib molecule expressed on the extravillous trophoblast and seems to have immunomodulatory functions during pregnancy. The purpose of our study was to investigate whether HLA-G may be a vital marker in the modulation of the pregnancy.

Methods: In this case-control study, a number of 150 healthy pregnant women and 150 patients with PE had been genotyped for the 14 base-pair (bp) insertion/deletion polymorphism in exon 8 of the HLA-G gene, and the serum level of soluble HLA-G (sHLA-G) protein was measured using the enzyme-linked immunosorbent assay.

Results: Data showed that the PE syndrome was not related to the HLA-G 14 bp genotype. But, the serum level of sHLA-G in PE patients was significantly lower than that in healthy pregnant women in the third trimester (11.74 and 24.48 U/ml, respectively, p < 0.001). However, no significant association was observed between the HLA-G 14 bp genotype and serum sHLA-G level.

Conclusion: Our results demonstrate that measurement of sHLA-G protein level may be helpful as a primary diagnosis for the pathogenesis of PE. Overall, this study suggests that the association between HLA-G 14 bp polymorphism and serum sHLA-G level in different ethnic populations of PE should be taken into consideration.

KEYWORDS:

• HLA-G
• polymorphism
• preeclampsia
• soluble HLA-G

Acknowledgments

The authors thank the Ahvaz Jundishapur University of Medical Sciences which supported this study. This article is the result of thesis for Saber Rokhafrooz to obtain a master degree in Immunology from AJUMS. The authors also thank the participating mothers who collaborated with samples for study analysis and the members of the Department of Obstetrics and Gynecology of the Imam Khomeini and Razi hospitals, Ahvaz, Iran.

Declaration of Interest

The authors report no conflicts of interest.

Additional information

Funding

This study was supported by a grant from the Ahvaz Jundishapur University of Medical Sciences (No. FIRC-9306).