Maternal circulating interferon‐γ and interleukin‐6 as biomarkers of Th1/Th2 immune status throughout pregnancy

Publisher Website
Google Scholar
Abstract
Aim:  T cells may be classified as T helper type 1 (Th1) cells, which synthesize cytokines inducing cellular immunity, or T helper type 2 (Th2), which synthesize cytokines inducing humoral immunity. According to the Th1/Th2 paradigm, it has been postulated that successful pregnancy induces an immune Th2 bias, but it is not yet clear how Th1 and Th2 systems vary simultaneously throughout the pregnancy.Methods:  Using maternal circulating interferon‐γ (IFN‐γ) and interleukin‐6 (IL‐6) as biomarkers of Th1 and Th2 cytokines, respectively, we examined the variation of circulating Th1/Th2 ratio in 35 healthy pregnant women from 10 to 40 weeks of pregnancy.Results:  With increasing gestational age, maternal circulating levels of IFN‐γ decrease, whereas those of IL‐6 increase. The IFN‐γ/IL‐6 ratio switches around the 19th week of pregnancy.Conclusions:  Our results suggest that maternal systemic IFN‐γ and IL‐6 concentrations may be biomarkers of Th1/Th2 immune status during pregnancy. Moreover, our findings showed that contrary to the Th1/Th2 paradigm, the Th1 bias may be prevailing at the beginning of pregnancy, balanced in the middle of pregnancy and supplanted by the Th2 bias at the end of pregnancy.