Abstracts (complete list) - Wissenschaft Online

Ana Teles, Catharina Thuere, Milan Popovic, Anne Schumacher, Paul Wafula, Hans-
Dieter Volk, Ana Zenclussen
Trafficking of regulatory T cells during pregnancy: Expression
profile of Treg-related chemokine and chemokine receptor at
the maternal-fetal interface.
Regulatory T cells (Treg) are shown to have an important role in the maintenance of
fetus tolerance along pregnancy. The mechanisms leading to the recruitment of these
cells at the fetal-maternal interface are still unknown, but like in other systems,
chemokines are likely to be involved.
Given the existent concordance between the expression of chemokines in the uterus/
placenta and their receptors in Treg, we selected several receptor-ligand pairs that may
be involved in the recruitment of these cells into the fetal-maternal tissues along
pregnancy. By real time RT-PCR we investigated the expression patterns of the selected
chemokine ligands in different phases of pregnancy (day 0, 2, 5, 8, 10 or 12 of
pregnancy) in uterus, decidua and placenta from normal pregnant C57/BL6-mated BALB/
c mice. Levels of Treg were analyzed by flow cytometry and by quantifying foxp3
mRNA.
Pregnant animals showed a gradual increase in the % of Treg in blood, spleen and
decidua along pregnancy as well as increased foxp3 mRNA levels at the fetal-maternal
interface. Regarding chemokines, our data suggest differential patterns of expression at
different time points. We observed a gradual up-regulation of CXCL12 in placenta
beginning on day 12 and of CCL21 in decidua beginning on day 10 of pregnancy.
CXCL12 was further found to be increased in decidual tissue with a peak on the 5th day
of pregnancy (implantation). For the chemokines CXCL13 and CCL20 no specific pattern
of expression could be found.
These results suggest different chemokines being responsible for the trafficking of Treg
at different pregnancy stages.