Placental release of distinct DNA-associated micro-particles into maternal circulation: reflective of gestation time and preeclampsia.
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.
Orozco
A F
AF
Department of Immunology, Baylor College of Medicine, Houston, TX, USA.
Jorgez
C J
CJ
Ramos-Perez
W D
WD
Popek
E J
EJ
Yu
X
X
Kozinetz
C A
CA
Bischoff
F Z
FZ
Lewis
D E
DE
D000293:Adolescent; D000328:Adult; D000469:Alkaline Phosphatase; D017209:Apoptosis; D002460:Cell Line; D055252:Cell-Derived Microparticles / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D004247:DNA / Q000032:analysis / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D058851:GPI-Linked Proteins; D006680:HLA Antigens / Q000032:analysis / Q000378:metabolism; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism; D010920:Placenta / Q000378:metabolism* / Q000473:pathology; D011225:Pre-Eclampsia / Q000097:blood* / Q000378:metabolism / Q000473:pathology; D011247:Pregnancy; D011264:Pregnancy Trimesters / Q000097:blood*; D014327:Trophoblasts / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
D058851:GPI-Linked Proteins; D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D007527:Isoenzymes; D004247:DNA; D000469:Alkaline Phosphatase; C019839:alkaline phosphatase, placental
Am J Pathol. 2008 Dec;173(6):1595-608
18974299
Ultrasound Obstet Gynecol. 2008 Aug;32(2):133-7
18615872
Clin Chem. 2005 Feb;51(2):312-20
15608152
Hypertens Pregnancy. 2002;21(1):77-83
12044339
Prenat Diagn. 2003 May;23(5):367-71
12749031
Hum Genet. 2003 Feb;112(2):204-8
12522563
Placenta. 2003 Nov;24(10):929-40
14580375
Hypertension. 2002 Jan;39(1):155-60
11799095
Hypertens Pregnancy. 2008;27(4):344-60
19003636
Ann N Y Acad Sci. 2006 Sep;1075:57-62
17108192
Prenat Diagn. 2004 Sep;24(9):722-6
15386446
Obstet Gynecol. 1995 Aug;86(2):289-92
7617363
Lancet. 1998 Dec 12;352(9144):1904-5
9863792
Hum Immunol. 2003 Feb;64(2):256-64
12559628
J Pathol. 1976 Mar;118(3):143-51
1263021
Histochem Cell Biol. 2002 May;117(5):401-14
12029487
J Immunol. 2007 May 1;178(9):5949-56
17442979
J Immunol Methods. 2006 Dec 20;317(1-2):45-55
17067632
Placenta. 2006 Jan;27(1):56-61
16310038
Reprod Sci. 2008 Dec;15(10):1002-10
18936439
Am J Obstet Gynecol. 2007 Sep;197(3):255.e1-5
17826409
Placenta. 2007 Nov-Dec;28(11-12):1141-6
17706280
Am J Obstet Gynecol. 2002 Jan;186(1):148-54
11810101
Am J Obstet Gynecol. 2002 Aug;187(2):450-6
12193942
Placenta. 2008 Mar;29 Suppl A:S73-7
18192006
Am J Obstet Gynecol. 2004 Mar;190(3):707-13
15042003
Hum Reprod Update. 2005 Jan-Feb;11(1):59-67
15569699
Clin Chem. 2001 Dec;47(12):2164-5
11719487
Am J Obstet Gynecol. 2005 Jul;193(1):204-8
16021080
Am J Obstet Gynecol. 2000 Sep;183(3):682-8
10992193
Hum Genet. 2005 Jul;117(2-3):243-8
15906093
Placenta. 2005 Apr;26 Suppl A:S31-6
15837064
J Clin Pathol. 2000 Jun;53(6):466-9
10911806
Br J Obstet Gynaecol. 1998 Jun;105(6):632-40
9647154
Am J Obstet Gynecol. 2004 Aug;191(2):525-9
15343231
Clin Chem. 2001 Jan;47(1):137-9
11148193
Am J Obstet Gynecol. 2004 Oct;191(4):1418-24
15507976