The association between low number of T regulatory cells, glycoprotein A repetitions predominant (GARP) expression, and short cervical length in preterm labour – results of a pilot study

Introduction
Glycoprotein A repetitions predominant (GARP) regulates the function of T regulatory cells. The aim of the study was to evaluate the relationship between the T regulatory cells (Treg) numbers, GARP expression and the incidence of preterm labour in women with a short cervix.

Material and methods
Fifty-nine pregnant patients were recruited at 20–35 weeks of gestation. The control group included 29 patients who had uncomplicated pregnancies, delivered at term. Thirty patients with singleton pregnancies were identified as being at risk of preterm birth, based on a short cervical length (< 25 mm) (with or without contractions).

Results
The levels of Tregs were significantly lower in patients with a short cervix compared to controls. In addition, the GARP expression was significantly reduced in women with a short cervix who delivered at term, but not in women with a short cervix who delivered preterm.

Conclusions
There was a positive correlation between the length of the cervix and the overall duration of pregnancy. Patients with a short uterine cervix had significantly lower levels of regulatory T cells, and those who delivered at term also had reduced levels of GARP. Despite the conflicting results, our work suggests a possible role for GARP in the mechanism of preterm labour.