Salivary Proteomic Profiling Identifies Role of Neutrophil Extracellular Traps Formation in Pregnancy Gingivitis

ABSTRACT

Pregnancy gingivitis peaks during mid-pregnancy and resolves transiently towards the postpartum period. However, the role of maternal immune response in orchestrating gingival inflammation has not yet been fully understood. Hence, in this study, we examined the salivary protein profile during the three trimesters of pregnancy, in context to pregnancy gingivitis, employing iTRAQ-based quantitative proteomics. Unstimulated saliva was collected from 10 subjects in each trimester of pregnancy and postpartum period. Samples were analysed using iTRAQ analysis and ELISA and SEM was performed to validate results. Neutrophil mediated immune response was overrepresented in all three trimesters of pregnancy, despite the decrease in phagocytic responses during the second and third trimesters. ELISA showed a significantly higher Neutrophil Extracellular Traps (NETs) formation in the third trimester of pregnancy coinciding with the resolution of pregnancy gingivitis. The NETs-associated proteins (neutrophil elastase and myeloperoxidase) showed a positive correlation with estrogen hormones, which was also highest during the third trimester. Sex hormone-driven NETs formation could be the mainstay of defence that contributes to the remission of pregnancy gingivitis. This study has provided a new insight into the role of immune-modulation in pregnancy gingivitis, which will aid development of new therapeutics for managing pregnancy gingivitis in future.

KEYWORDS:

• Pregnancy
• proteomics
• immunity
• gingivitis
• saliva
• neutrophil

Disclosure statement

There is no conflict of interest

Data availability

The proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE (Vizcaino et al. 2016) partner repository with the dataset identifier PXD010259.

Additional information

Funding

This study was supported by the Oral Health Seed Grant, Faculty of Dentistry [000-076-733], Sunstar Donation Grant [000-111-720] and SingHealth Duke NUS NDRIS grant [11/FY2019/G1/02-A44] to C.J.S.