research day - University of Toronto Department of Obstetrics and ...

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ABSTRACT #P-B2
LACTOBACILLUS RHAMNOSUS GR-1 STIMULATES GRANULOCYTE-COLONY
STIMULATING FACTOR (G-CSF) OUTPUT IN PLACENTAL TROPHOBLAST CELLS
IN A FETAL SEX-DEPENDANT MANNER
Maryam Yeganegi[G](1,3), Chiashan G Leung(1), Andrew Martins(2), Sung O Kim(2), Gregor
Reid(2), John RG Challis (1), Alan D Bocking(1,3).
(1) Department of Physiology & Obstetrics and Gynaecology, University of Toronto (2)
Department of Microbiology & Immunology, University of Western Ontario, London, Ontario, (3)
Samuel Lunenfeld Research Institute, Mount Sinai Hospital.
Objective: Bacterial Vaginosis (BV) is associated with a 1.4-fold increased risk of preterm birth.
Studies have shown that there is a higher incidence of spontaneous preterm birth and poorer
neonatal outcome in pregnancies with a male fetus. We have shown previously that Lactobacillus
rhamnosus GR-1 cell culture supernatant up-regulates IL-10 output in LPS-treated human
placental trophoblast cells. We hypothesize that lactobacilli exerts its anti-inflammatory effect
through up-regulation of G-CSF which is dependent on the sex of the fetus.
Methods: Term placentae were collected from women undergoing elective Caesarean section.
Placental trophoblasts were isolated using established primary culture protocols. Cells were treated
with lipopolysaccharide (LPS) in the presence or absence of pretreatments with GR-1 cell culture
supernatant or chemical inhibitors of the intracellular signaling pathways. Phosphorylations of p38
and STAT3 were measured by Western Blot analysis and output of G-CSF and IL-10 were
determined by ELISA.
Results: G-CSF output was increased relative to control only in the female placental trophoblast
cells treated with LPS (>233.1-fold), GR-1 cell culture supernatant (>588.7-fold) and a
combination of both treatments (>737.1-fold) (n=6 females, n=5 males, p=0.002). Phosphorylation
of STAT-3 was up-regulated with GR-1 supernatant alone (>1.7-fold) and when combined with
LPS (>1.8-fold) (n=10, p=0.018). In addition, p38 phosphorylation was increased with LPS (>1.3-
fold), GR-1 supernatant (>2.1-fold) and combination of both treatments (>2.1-fold) (n=4,
p=0.005). IL-10 output was inhibited by both JAK and p38 inhibitors (n=9, P