Measuring gene expression and immune level of FOXP3 and its relationship with regulatory T cells in maintaining immune tolerance in both women pregnant and recurrent miscarriage, who suffer from autoimmune thyroid diseases

Autoimmune thyroid diseases (AITD) is the most common human autoimmune disease. It was found that one of the causes of its occurrence is an imbalance of the immune system of regulatory T (Treg) cells and a decrease in their transcription factor FOXP3. The objective: to investigate the relationship between Treg cells and FOXP3 in persons with AITD and to measure the gene expression level of FOXP3 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in pregnant women and women with recurrent pregnancy loss who have AITD. Materials and methods. 90 women were examined. Among them 70 patients with autoimmune thyroid diseases and elevated levels of antibodies to thyroperoxidase were divided into 35 pregnant women and 35 women with a history of recurrent miscarriages. The control group included 20 healthy women without AITD. All women were tested for FOXP3 protein levels and FOXP3 and GAPDH gene expression.Results. The results showed a highly statistically significant difference in the level of regulatory T cells (p ≤ 0.001) between the indicators of pregnant patients with AITD and women with recurrent miscarriage and AITD. The mean value in both groups was 1.7791 ± 0.4344 ng/ml and 0.9420 ± 0.1028 ng/ml, respectively.Highly statistically significant difference (p ≤ 0.001) in the levels of FOXP3 protein between pregnant patients with AITD and patients with recurrent miscarriage and AITD was determined. The mean value of FOXP3 protein level was 1.3639 ± 0.2199 ng/ml and 0.7389 ± 0.2009 ng/ml, respectively. FOXP3 gene expression had significant differences between groups (p ≤ 0.001) – it was higher in patients with autoimmune thyroid diseases (pregnant women and women with recurrent miscarriage) compared to the control group. The mean value was 2.538 ± 0.347 and 1.056 ± 0.231, respectively.Conclusions. The results demonstrated a relationship between the levels of regulatory T cells, and the level of FOXP3 protein and autoimmune thyroid diseases and their outcome in cases of recurrent miscarriages. It was found that the expression of the FOXP3 gene was higher in patients with autoimmune thyroid diseases (pregnant women and women with recurrent miscarriages) compared to healthy women.