Placental Release of Distinct DNA-associated Micro-particles into Maternal Circulation: Reflective of Gestation Time and Preeclampsia

Orozco, A.F.; Jorgez, C.J.; Ramos-Perez, W.D.; Popek, E.J.; Yu, X.; Kozinetz, C.A.; Bischoff, F.Z.; Lewis, D.E.

doi:10.1016/j.placenta.2009.06.012

« Previous Next »Placenta
Volume 30, Issue 10 , Pages 891-897, October 2009

Placental Release of Distinct DNA-associated Micro-particles into Maternal Circulation: Reflective of Gestation Time and Preeclampsia

A.F. Orozco
- Department of Immunology, Baylor College of Medicine, Houston, TX, USA
C.J. Jorgez
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
W.D. Ramos-Perez
- Department of Immunology, Baylor College of Medicine, Houston, TX, USA
E.J. Popek
- Department of Pathology, Baylor College of Medicine, Houston, TX, USA
X. Yu
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
C.A. Kozinetz
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
F.Z. Bischoff
- Biocept Inc., San Diego, CA, USA
D.E. Lewis
- Department of Immunology, Baylor College of Medicine, Houston, TX, USA
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USA
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Corresponding author. Department of Internal Medicine, Infectious Diseases Division, University of Texas Medical Branch, 301 University Boulevard, Mail Route 0435, Galveston, TX 77555, USA. Tel.: +1 409 747 0240; fax: +1 409 772 6527.

Accepted 29 June 2009. published online 19 August 2009.

Abstract

Background

The aim of this study was to determine whether DNA-associated micro-particles (MPs) in maternal plasma express fetal-derived human leukocyte antigen-G (HLA-G) or placental alkaline phosphatase (PLAP) and whether the levels differ between women with normotensive pregnancies and preeclampsia.

Methods

DNA-associated MPs expressing HLA-G or PLAP were examined in the plasma of normal pregnant women and preeclamptic patients using flow cytometric analysis.

Results

DNA-associated HLA-G⁺ MPs were significantly increased in maternal plasma compared to plasma from non-pregnant controls (p<0.005), with highest levels found in the first and second trimesters. DNA-associated PLAP⁺ MPs were also increased in maternal plasma compared to plasma from non-pregnant controls (p<0.006), with highest levels in the second and third trimesters. Term preeclamptic women had higher levels of DNA-associated MPs than control pregnant women. HLA-G⁺ MPs from the plasma of preeclamptic women had more DNA per MP than HLA-G⁺ MPs from the plasma of normal pregnant women (p<0.03).

Conclusions

HLA-G⁺ and PLAP⁺ MPs increase in maternal circulation at different times during gestation. DNA amounts per HLA-G⁺ MP increase in preeclamptic women which might indicate dysfunctional extravillous cytotrophoblasts.

Keywords: Apoptotic micro-particles, Fetal DNA, DNA-associated micro-particles, HLA-G, PLAP, Preeclampsia, Syncytiotrophoblast, Extravillous cytotrophoblast