Poster Presentation Australasia Extracellular Vesicles Conference 2017

Contribution of placenta exosomes to the total exosomes present in maternal circulation during gestation and their potential role in maternal inflammation (#61)

Carlos Salomon 1 2 , Omar Elfeky 3 , Sherri Longo 2 , Carlos Palma 1 , Andrew Lai 1 , Gregory E Rice 1 2
  1. Exosome Biology Laboratory, Centre for Clinical Diagnostics (CCD), University of Queensland Centre for Clinical Research (UQCCR), Brisbane, QLD, Australia
  2. Department of Obstetrics and Gynecology, Ochsner Baptist Hospital, New Orleans, Louisiana, USA
  3. University of Queensland Centre for Clinical Research, Centre for clinical diagnostics, Royal Brisbane and Women's Hospital , Brisbane, QLD, Australia

Recent studies report that 52% of women are either overweight or obese, 35% of whom were of reproductive age (25-35 years). During pregnancy, the placenta releases exosomes into maternal circulation, and their concentration is higher in pregnancy complications. We aim to establish the relationship between maternal BMI and exosomes present in maternal circulation during gestation.

Plasma samples were classified according to the maternal BMI into three groups (n=15 per group): Lean, overweight (OW), and obese. The total number of exosomes and specific placenta-derived exosomes were determined by Nanoparticle Tracking Analysis (NanoSight™) using quantum dots coupled with CD63 or PLAP antibodies. The effect of exosomes on cytokine (IL-6. IL-8, IL-10 and TNF-α) release from endothelial cells (EC) was established by the protein solution array analysis (Bioplex-200). 

RESULTS: The total number of exosomes present in maternal circulation was strongly correlated with maternal BMI. Between ~12% and ~25% of circulating exosomes in maternal blood are of placental origin during gestation, and the contribution of placental exosomes to the total exosomal population decreases with higher maternal BMI across gestation. Exosomes increase IL-6, IL-8 and TNF-α release from EC, and effect even higher when exosomes were isolated from obese women compare to Lean and OW.  Gestational-age changes on the effect of exosomes on cytokines releases from EC were also identified.

CONCLUSIONS: This study established that maternal BMI is a factor that explains a significant component of the variation in the exosomes data. Exosomes may contribute to the maternal systemic inflammation during pregnancy.