Amniotic fluid soluble human leukocyte antigen-G in term and preterm parturition, and intra-amniotic infection/inflammation.
OBJECTIVE
Circulating soluble human leukocyte antigen-G (sHLA-G) has been associated with pregnancy complications, and determination of sHLA-G concentrations in amniotic fluid (AF) has been reported in normal pregnancies. Our aim was to determine if the AF concentrations of sHLA-G change with advancing gestation, spontaneous labor at term, and in patients with spontaneous preterm labor (PTL) with intact membranes, as well as in those with preterm prelabor rupture of membranes (PROM), in the presence or absence of intra-amniotic infection/inflammation (IAI).


METHODS
This cross-sectional study included the following groups: (1) mid-trimester (n = 55); (2) normal pregnancy at term with (n = 50) and without (n = 50) labor; (3) spontaneous PTL with intact membranes divided into: (a) PTL who delivered at term (n = 153); (b) PTL who delivered preterm without IAI (n = 108); and (c) PTL with IAI (n = 84); and (4) preterm PROM with (n = 46) and without (n = 44) IAI. sHLA-G concentrations were determined by ELISA. Non-parametric statistics were used for analysis.


RESULTS
(1) Among patients with PTL, the median AF sHLA-G concentration was higher in patients with IAI than in those without IAI or women that delivered at term (p < 0.001 for both comparisons); (2) Similarly, patients with preterm PROM and IAI had higher median AF sHLA-G concentrations than those without IAI (p = 0.004); (3) Among patients with PTL and delivery, those with histologic chorioamnionitis and/or funisitis had a higher median AF sHLA-G concentration than those without histologic inflammation (p < 0.001); and (4) The median AF sHLA-G concentration did not change with advancing gestational age.


CONCLUSIONS
AF sHLA-G concentrations are elevated in preterm parturition associated to IAI as well as in histologic chorioamnionitis. We propose that sHLA-G may participate in the regulation of the host immune response against intra-amniotic infection.
Kusanovic
Juan Pedro
JP
Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, Maryland, USA.
Romero
Roberto
R
Jodicke
Cristiano
C
Mazaki-Tovi
Shali
S
Vaisbuch
Edi
E
Erez
Offer
O
Mittal
Pooja
P
Gotsch
Francesca
F
Chaiworapongsa
Tinnakorn
T
Edwin
Sam S
SS
Pacora
Percy
P
Hassan
Sonia S
SS
D000328:Adult; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000737:chemistry*; D002821:Chorioamnionitis / Q000378:metabolism*; D003430:Cross-Sectional Studies; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000378:metabolism / Q000473:pathology; D005865:Gestational Age; D006680:HLA Antigens / Q000032:analysis* / Q000378:metabolism; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000378:metabolism; D047928:Premature Birth / Q000378:metabolism*; D020033:Protein Isoforms / Q000032:analysis / Q000378:metabolism; D047929:Term Birth / Q000378:metabolism*
D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D020033:Protein Isoforms