Galectin signature of the choriocarcinoma JAr cells: Galectin-1 as a modulator of invasiveness in vitro.

Our previous findings showed that galectin-1 (LGALS1) plays an important role in the in vitro invasion of normal human trophoblast cells. In the present study, choriocarcinoma JAr cells were found to express LGALS1, -2, -3, -8, -10, and -13 mRNA and at least LGALS1, -3, and -8 protein, as determined by reverse-transcriptase PCR and Western blot, respectively. The galectin mRNA signature of JAr cells thus differed from that of normal first-trimester extravillous trophoblasts. A Matrigel migration assay was also used to investigate and confirm the relevance and effect of LGALS1 on the invasive potential of JAr cells, as observed in other trophoblast models. This modulation in behavior was achieved by specific lectin-glycan binding.

Immunoglobulins from sera of antiphospholipid syndrome patients are internalized in the HTR-8/SVneo cell line and cytotrophoblast in culture.

Women with antiphospholipid syndrome (APS) experience pregnancy complications mostly due to impaired trophoblast cell functions. Antiphospholipid antibodies (aPL) affect extravillous trophoblast in vivo and in culture, but the mechanisms are still poorly understood. Previously, syncytiotrophoblast was shown to bind and internalize aPL, which was not replicated for extravillous cytotrophoblast in short term culture. Here, aPL binding and time dependent internalization was demonstrated with exposure to aPL in the extravillous cell line HTR-8/SVneo and isolated first trimester of pregnancy cytotrophoblast (CT) using immunocytochemistry and flow cytometry. Intracellular aPL were detectable from 2 h of culture, reaching 30.7 ±â€¯3.1% (p < 0.001) positive cells in CT and 24.8 ±â€¯7% (p < 0.01) in HTR-8/SVneo cells at 24 h and 33 ±â€¯4.2% (p < 0.01) at 48 h. The data presented show that extravillous trophoblast cells internalize aPL in a time-dependent manner significantly more than control immunoglobulins after 24 h of exposure.

Immunoglobulins from sera of APS patients bind HTR-8/SVneo trophoblast cell line and reduce additional mediators of cell invasion.

Immunoglobulins from sera of patients with antiphospholipid syndrome (APS) decrease trophoblast cell invasion in vitro. This study aimed to extend understanding of cellular effects of immunoglobulins from APS (aPL+) in HTR-8/SVneo cells. aPL+ IgG induced change in effector molecules important for cell invasion was investigated further. After 1h of culture 21% cells bound aPL+ IgG, as opposed to 6% in control (aPL-). This was accompanied by increase in phospho-p38 at 30min. After 24h treatment aPL+IgG decreased protein levels of integrin subunits α1 (78% of control; p<0.01), α4 (65% of control, p<0.01), α5 (76% of control; p<0.01) and ß1 (80% of control; p<0.01), and secreted gal-1 (68% of control; p<0.05). ProMMP-9 was reduced to 70% of control (p<0.001). Treatment with inhibitor of p38 MAPK signaling SB202190 reversed inhibition in integrin ß1 and secreted gal-1. Involvement of p38 MAPK signaling and decrease in integrin subunit α4, proMMP-9, and secreted gal-1 in HTR-8/SVneo cells are novel and extend the list of mediators of trophoblast invasion affected by aPL.

Histological chorioamnionitis in preterm prelabor rupture of the membranes is associated with increased expression of galectin-3 by amniotic epithelium.

PURPOSE: Gal-3, which can regulate immune responses upon infection and inflammation, was not studied so far in intrauterine infection leading to preterm prelabor rupture of the membranes (PPROM), although gal-1 was reported to be implicated in the process. Gal-3 mRNA and protein expression in amnion and its changes during histological chorioamnionitis were studied here. MATERIALS AND METHODS: Fetal membranes were obtained from women with PPROM with (n =15) and without histological chorioamnionitis (n =15) during second and third trimester. Immunohistochemical reactivity was evaluated semiquantitatively and analyzed using t-test. Galectin profile of amniotic epithelia was determined by polymerase chain reaction (PCR) and change assessed in gal-3 in PPROM with (n =5) or without histological chorioamnionitis (n =5) by real-time PCR. RESULTS: Human amniotic epithelium was found to express gal-1, gal-3, gal-7 and gal-8 mRNA. Gal-3 mRNA and protein is increased in fetal membranes and in the amniotic epithelium in patients with chorionamnionitis. CONCLUSION: Histological chorioamnionitis is associated with increased gal-3 expression and strong immunoreactivity of the amnion. Gal-3 may participate in the regulation of the inflammatory responses to chorioamniotic infection and/or direct interaction with pathogens.