Snps and transcriptional activity of genes of innate and adaptive immunity at the maternal-fetal interface in woman with preterm labour, associated with preterm premature rupture of membranes

Abstract

The aim is to identify mRNA expression of innate (TLR2 and TLR4) and adaptive (IL1 β, IL17A, FoxP3, Tbet, Roryt) immunity in maternal-fetal interface and evaluate the contribution of SNP genes of IL1β (rs1143627), TNFα (rs1800629), IL4 (rs2243250), IL10 (rs1800896, rs1800872) and RLN2 (rs4742076, rs3758239) to PTB, associated with PPROM in 26-34 weeks of gestation. Materials and methods: We had done open cohort randomized research during period 2016-2018 years. The case group consisted of 50 women with PPROM in preterm pregnancy, 26-34 weeks of gestation. For the control group we collected samples from 50 women without previous history of PTB. To determine the level of mRNA target genes we used thermocycler CFX96™Real-Time PCR Detection Systems (“Bio-Rad Laboratories, Inc.”, USA) and set of reagents Maxima SYBR Green / ROX qPCR MasterMix (2x) (Thermo Scientific, USA). Results: In the population of the Zaporizhzhia region, there is no reliable clinical association between the IL1β and TNFα genes and a high risk of PTB. We obtained high reliable data on SNP genes RLN2 rs4742076 and rs3758239 in Zaporizhzhia women. The distribution of the rs2243250 gene polymorphism alleles of the IL4 gene of the main study group – TT homozygotes were determined in 2 (4%) cases, CT heterozygotes were found in 11 (22%), CC homozygotes in 37 (74%) cases. In the study of polymorphism rs1800872 of the IL10 gene, the main group of homozygous TT studies was identified in 7 (14%) cases, TG heterozygotes were found in 18 (36%), GG homozygotes in 25 (50%) cases. The range of all obtained values of the relative normalized expression of TLR2 gene in the placenta of 0.79-163.44 (median – 31.06), in the fetal membranes – 1.1-126.06 (median – 10.22). The placement of all obtained values compared to mRNA expression of the TLR4 gene was lower than the TLR2 in the placenta, which was 0.39-43.85 (median – 7.74) and higher in the fetal membranes – 0.18-216.01 (median – 40.04). We observed an 8.33-fold decreased expression in FoxP3 in decidua, especially in 31-32 weeks of PPROM manifestation (27.03-fold). In amniotic membranes a similar trend of reduction of FoxP3 expression was found, overall level decreased in 2.33 times, especially in 31-32 weeks of PPROM manifestation (10.64-fold). Conclusions: Among Zaporizhzhia population, combination of IL4 (rs2243250), IL10 (rs1800896 and rs1800872), RLN2 (rs4742076 and rs3758239) supports the role for functional polymorphisms in immunoregulatory genes in the susceptibility to PTL, associated with PPROM. Marked increased transcriptional activity of components of innate (TLR2, TLR4), adaptive (Th1, Th17) immune system and conversely decreased expression of Treg (FoxP3) in the maternal-fetal interface are involved in immune pathways of PTB and contribute in the fetal inflammatory response syndrome.