Osteopontin facilitates invasion in human trophoblastic cells via promoting matrix metalloproteinase-9 in vitro

Successful implantation of embryo and placentation depend on proper trophoblast proliferation and differentiated into specialized invasive trophoblast. However, little is known about the regulatory factors and mechanisms in trophoblast proliferation and differentiation. Osteopontin (OPN) is a member of the small integrin-binding ligand N-linked glycoprotein family and participates in cell adhesion and invasion. It has been identified that OPN is highly expressed in invasive trophoblasts in human placenta. In this study, we demonstrated that OPN is constitutively expressed in highly invasive phenotype of human choriocarcinoma cell lines of JAR and JEG-3 cells, and OPN could promote trophoblast proliferation and invasion, partly through promoting MMP-9 secretion. Inhibition of OPN will compromise the abilities of proliferation and invasion in JAR and JEG-3 cell lines. Our data showed that the expression of OPN in trophoblast may participate in placentation, OPN expression defects may be involved in gestational trophoblastic diseases.     

Expression of functional Fas ligand in choriocarcinoma

PROBLEM: In the course of pregnancy, fetal trophoblast cells and in that of choriocarcinoma-etiology, trophoblast derived tumor cells, invade the uterine mucosa without causing rejection by decidual leukocytes. Fas ligand (FasL, CD95L, APO-IL), a central regulator of the immune system, has been implicated in the maintenance of immune privileged sites, such as the eye, the testis and the pregnant uterus by inducing apoptosis in activated infiltrating leukocytes. In normal pregnancy FasL, which is expressed by trophoblast cells, appears to contribute to the immune privilege of the pregnant uterus. As choriocarcinoma derives from trophoblast we wanted to assess the expression of FasL in this tissue. METHOD OF STUDY: Immunohistochemistry, immunofluorescence, TUNEL-assay, Western blotting, coculture experiments and flourescence-associated cell sorter-analysis were the techniques used. RESULTS: Expression of FasL was found on cells of choriocarcinoma in paraffin sections in situ and on three choriocarcinoma cell lines such as JEG-3, JAR and BeWo. These results were confirmed by Western blotting. In coculture experiments choriocarcinoma cells induced apoptosis in a Jurkat cell line - sensitive to FasL mediated killing. However, when the Jurkat cells were pre-incubated with a Fas-blocking monoclonal antibody, apoptosis was abolished to a great extent. CONCLUSION: Our findings show that choriocarcinoma cells express FasL and this aforementioned molecule is biologically active. We assume that FasL expression on choriocarcinoma cells may contribute to control of anti-tumor responses by inducing apoptosis in activated Fas bearing leukocytes.     

Transfected trophoblast-derived human cells can express a single HLA class I allelic product

The human trophoblast-derived JAR cell line, that does not express polymorphic HLA class I antigens even after IFN induction, can be stably transfected by genomic clones encoding the entire HLA-A2, -A3 and -B7 alpha-chain genes. The transfected genes were expressed at the cell surface in association with endogenous beta 2-microglobulin (shown by FCM analysis) as a single allelic product without reexpression of any endogenous class I gene (shown by 1D.IEF analysis). Furthermore, TNF-alpha and IFN-gamma, alone and synergistically, increase cell surface expression of transfected MHC class I/endogenous beta 2m heterodimers without induction of endogenous class I alpha-chain genes. These data show that the MHC class I-negative JAR human cell line might be used for transfections with the aim of establishing human cells expressing just one defined MHC class I allele for functional and regulatory studies. These findings are discussed in relation to the methylated status solely of endogenous class I alpha-chain genes in JAR cells and suggest that transfected class I genes are not regulated in the same fashion and, in particular, that constitutive and TNF/IFN inducible trans-acting regulatory factors able to bind to cis-promoter/enhancer sequences of class I DNA are likely to be present.     

Human leucocyte antigen (HLA) expression of primary trophoblast cells and placental cell lines,determined using single antigen beads to characterize allotype specificities of anti-HLA antibodies

Human trophoblast cells express an unusual repertoire of human leucocyte antigen (HLA) molecules which has been difficult to define. Close homology between and extreme polymorphism at the classical HLA class-I (HLA-I) loci has made it difficult to generate locus-specific monoclonal antibodies (mAbs). The problem of defining an antibody''s reactivity against the thousands of existing HLA-I allotypes has often made it impossible to determine the HLA bound by a mAb in biological samples from a normal outbred population. Here we have used commercially available beads coated with individual HLA-I to characterize experimentally the reactivity of nine mAb against 96 common HLA-I allotypes. In conjunction with donor HLA-I genotyping, we could then define the specific HLA molecules bound by these antibodies in normal individuals. We used this approach to analyse the HLA expression of primary trophoblast cells from normal pregnancies; the choriocarcinoma cells JEG-3 and JAR; and the placental cell lines HTR-8/SVneo, Swan-71 and TEV-1. We confirm that primary villous trophoblast cells are HLA null whereas extravillous trophoblast cells express HLA-C, HLA-G and HLA-E, but not HLA-A, HLA-B or HLA-DR molecules in normal pregnancy. Tumour-derived JEG-3 and JAR cells reflect extravillous and villous trophoblast HLA phenotypes, respectively, but the HLA repertoire of the in vitro derived placental cell lines is not representative of either in vivo trophoblast phenotype. This study raises questions regarding the validity of using the placental cell lines that are currently available as model systems for immunological interactions between fetal trophoblast and maternal leucocytes bearing receptors for HLA molecules.     

The use of Alamar Blue assay for quantitative analysis of viability, migration and invasion of choriocarcinoma cells

BACKGROUND: The current techniques for quantifying trophoblast viability, migration and invasion are mainly limited by the need to sacrifice the cells during the test procedure. In this study, the vital dye AB (AB) was used to quantify cell number and viability of BeWo and JEG-3 choriocarcinoma cells, as well as their migration and invasion through fibronectin-coated filters. METHODS :AB was directly added to culture medium of incubated test and control cells. At various time intervals, the redox reaction, in which AB is reduced by the cells, was measured by absorbance readings at 540 and 630 nm. For cell migration and invasion, cells were cultured onto uncoated or fibronectin-coated inserts, respectively. AB reduction of migrated cells was normalized to that of control cells to calculate percentages of migration. This model was also tested in the presence of a reported inhibitor, transforming growth factor (TGF) beta. RESULTS: The curve of %AB reduction versus cell number was linear, with intra- and inter-assay Coefficient of Variations of 1.88%and 2.94%, respectively. AB reduction increased with both seeding concentrations and incubation time with AB. TGFbeta treatment caused a modest decrease in AB reduction in both JEG-3 and BeWo cells. TGFbeta treatment also decreased migration in BeWo, but not in JEG-3, cells. CONCLUSIONS: AB assay is a simple and reliable method for quantifying trophoblast viability, migration and invasion.     

Immunohistochemical evidence of p53 protein in human placenta and choriocarcinoma cell lines

We investigated the expression of the tumour-suppressor andcell cycle control protein p53 in human first trimester andterm placenta, three choriocarcinoma cell lines (Jeg-3, JAR,BeWo) and human choriocarcinoma. Using monoclonal antibodiesagainst p53 (DO-7, Ab-6, DO-1, PAb 1801), paraffin-embeddedsections of first trimester and full-term placentae, human choriocarcinomaand Jeg-3, JAR and BeWo, as well as cytospins, were evaluatedimmunohistochemically. In addition, Western blots were carriedout with the same antibodies on choriocarcinoma cell lines.In placentae, a small number of villous and extravillous cytotrophoblastcells, as well as very few syncytiotrophoblast cells, stainedintensively. Also, p53 was visualized in some nuclei of theplacental basal plate, whereas stroma and endothelium were negativefor p53. Jeg-3, JAR and BeWo also showed a positive nuclearreaction with all applied antibodies. In paraffin-embedded sectionsof human choriocarcinoma, staining was confined to the nucleiof malignant cells. The results suggest that p53 is overexpressednot only in malignant tumour cells but in certain trophoblastcell populations of the human placenta as well. choriocarcinoma cells/human placenta/immunohistochemistry/p53     

Cell proliferation and apoptosis: Immunohistochemical evidence of p53 protein in human placenta and choriocarcinoma cell lines

We investigated the expression of the tumour-suppressor andcell cycle control protein p53 in human first trimester andterm placenta, three choriocarcinoma cell lines (Jeg-3, JAR,BeWo) and human choriocarcinoma. Using monoclonal antibodiesagainst p53 (DO-7, Ab-6, DO-1, PAb 1801), paraffin-embeddedsections of first trimester and full-term placentae, human choriocarcinomaand Jeg-3, JAR and BeWo, as well as cytospins, were evaluatedimmunohistochemically. In addition, Western blots were carriedout with the same antibodies on choriocarcinoma cell lines.In placentae, a small number of villous and extravillous cytotrophoblastcells, as well as very few syncytiotrophoblast cells, stainedintensively. Also, p53 was visualized in some nuclei of theplacental basal plate, whereas stroma and endothelium were negativefor p53. Jeg-3, JAR and BeWo also showed a positive nuclearreaction with all applied antibodies. In paraffin-embedded sectionsof human choriocarcinoma, staining was confined to the nucleiof malignant cells. The results suggest that p53 is overexpressednot only in malignant tumour cells but in certain trophoblastcell populations of the human placenta as well.     

The Role of Placental Trophoblast in the Pathophysiology of the Antiphospholipid Antibody Syndrome

PROBLEM: The antiphospholipid (aPL) antibody syndrome is characterized by severe pregnancy complications, the cause of which remains unknown. We hypothesized that the placental trophoblast is a target for aPLs. METHOD OF STUDY: The effects of monoclonal aPLs on trophoblast function, including the invasion of JAR into matrigel-coated filters and the effects of annexin V expression on BeWo, were investigated using choriocarcinoma models. RESULTS: aPLs against phosphatidylserine (PS) significantly (P < 0.001) decreased the migration of JAR across the membrane. In the annexin V studies, undifferentiated BeWo did not express surface annexin V. After differentiation, BeWo expressed surface annexin V, which was removed in the presence of aPLs, resulting in increased binding of prothrombin. CONCLUSIONS: PS is expressed on the trophoblast surface during differentiation and invasion of extracellular matrix. Our data suggest that aPLs against PS can directly affect trophoblast function by limiting the depth of decidual invasion and by concurrently creating a procoagulant surface on trophoblast exposed to the maternal circulation.     

Differential effects of inducers of syncytialization and apoptosis on BeWo and JEG-3 choriocarcinoma cells

BACKGROUND: The interactions of trophoblasts with the cytokine network at the fetomaternal interface determine the pathway the cell undertakes, e.g. proliferation, differentiation and apoptosis. METHODS: We used cultures of fusigenic BeWo and non-fusigenic JEG-3 choriocarcinoma cells to study the effects of inducers of syncytialisation (forskolin) and apoptosis [tumour necrosis factor-alpha (TNFalpha)] on differentiation, viability, proliferation and apoptosis. RESULTS: E-cadherin immunostaining showed that syncytium formation was confined to BeWo and not JEG-3 cells, while secretion of hCG was promoted by forskolin in both cell types implying a 'dissociation' between morphological and biochemical differentiation. Forskolin also had differential effects on cell viability (MTT reduction test) and proliferation (Ki67 immunostaining with MIB-1 monoclonal antibody), both decreasing in BeWo and increasing in JEG-3 cells. TNFalpha increased apoptosis (cytokeratin neo-epitope immunostaining with M30 monoclonal antibody) in both cell types, an effect which was blocked by epidermal growth factor selectively in JEG-3 cells. CONCLUSION: Our results suggest that the differential responses of BeWo and JEG-3 cells to inducers of syncytialization and apoptosis might be related to their fusigenic capacity. Caution is needed when extrapolating results obtained by these models to normal trophoblast populations. However, we speculate that these models can help identify key factors involved in trophoblast differentiation at the placental bed.     

Effects of Notch2 and Notch3 on Cell Proliferation and Apoptosis of Trophoblast Cell Lines

Aims: To investigate the effect of Notch2 and Notch3 on cell proliferation and apoptosis of two trophoblast cell lines, BeWo and JAR.Methods: Notch2 and Notch3 expression in BeWo and JAR cells was upregulated or downregulated using lentivirus-mediated overexpression or RNA interference. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. The effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V-PE Apoptosis kit. Lentivirus-based overexpression vectors were constructed by cloning the full-length coding sequences of human Notch2 and Notch3 C-terminally tagged with GFP or GFP alone (control) into a lentivirus-based expression vector. Lentivirus-based gene silencing vectors were prepared by cloning small interfering sequences targeting human Notch2 and Notch3 and scrambled control RNA sequence into a lentivirus-based gene knockdown vector. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. And the effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V PE Apoptosis kit.Results: We found that the downregulation of Notch2 and Notch3 gene expression in BeWo and JAR cells resulted in an increase in cell proliferation, while upregulation of Notch3 and Notch2 expression led to a decrease in cell proliferation. Moreover, the overexpression of Notch3 and Notch2 in BeWo and JAR cells reduced apoptosis in these trophoblast cell lines, whereas apoptosis was increased in the cells in which the expression of Notch3 and Notch2 was downregulated.Conclusions: Notch2 and Notch3 inhibited both cell proliferation and cell apoptosis in BeWo and JAR trophoblast cell lines.     

Expression of membrane and nuclear progesterone receptors in two human placental choriocarcinoma cell lines (JEG-3 and BeWo): Effects of syncytialization

A vital function of the human placenta is to produce steroid hormones such as progesterone, which are essential for the maintenance of pregnancy and the onset of parturition. Although choriocarcinoma cell lines are valuable placental models for investigations of steroid hormone actions, little is known about the expression of progesterone receptors (PRs) in these cell lines. Therefore, in this study, the expression of membrane and nuclear PRs was investigated in cultures of fusigenic (BeWo) and non-fusigenic (JEG-3) human choriocarcinoma cell lines. In addition, the effects of an inducer of syncytialization (forskolin) on the PR expression in BeWo cells were assessed. Quantitative RT-PCR revealed that in fully syncytialized BeWo cells (treated with 50 μM forskolin for 72 h) there was a significant down-regulation of mPRα and up-regulation of mPRβ and of the progesterone membrane component-1 (PGRMC1) when compared with non-syncytialized BeWo cells. Expression of all the mPR and PGRMC1 mRNAs was significantly lower in JEG-3 cells compared to non-syncytialized BeWo cells. Interestingly, expression of PR-B was unaltered between the two BeWo states but was significantly higher in JEG-3 cells. Immunofluorescence analysis revealed that mPR proteins are differentially expressed in these choriocarcinoma cell lines as well as in the human placenta. The data demonstrate that human choriocarcinoma cell lines have a complex system of progesterone signalling involving multiple classes of PRs. The finding that syncytialization is accompanied by changes in the expression of these receptors may suggest that this process influences progesterone signalling.     

Mucin 15 is expressed in human placenta and suppresses invasion of trophoblast-like cells in vitro

BACKGROUND: Trophoblast invasion is crucial for the development of normal placentas. Mucins are suggested to be involved in cancer invasion. However, the function of mucins in trophoblast invasion has never been reported. This study was to investigate the expression of mucin (MUC) 15 in human placenta and its role in trophoblast invasion. METHODS: MUC15 mRNA in human tissues was analyzed by Northern blot. MUC15 mRNA and protein in human placenta were detected by real-time RT-PCR and Western blot, respectively. The distribution of MUC15 was revealed by immunohistochemistry. The effects of MUC15 on trophoblast invasion in vitro were analyzed by matrigel invasion assay in human choriocarcinoma JAR and JEG-3 cells. RESULTS: MUC15 was expressed most highly in human placenta. MUC15 mRNA and protein increased with gestational age (P < 0.05, first versus third trimester). Immunohistochemistry showed that MUC15 protein was expressed by both cytotrophoblasts and syncytiotrophoblasts, especially at the apical membrane of syncytiotrophoblasts. In addition, MUC15 was found to be present in the glandular epithelium of the decidua. Overexpression of MUC15 substantially decreased matrigel invasion of JAR and JEG-3 cells by 87.5 +/- 1.1 and 83.8 +/- 5.7%, respectively, versus control, which was closely associated with an increase in mRNA expression of tissue inhibitors of metalloproteinases (TIMP)-1 and TIMP-2. Knockdown of MUC15 with small interfering RNA significantly reversed these effects (P < 0.05). CONCLUSIONS: Differential expression of MUC15 in human placentas may play a critical role in the regulation of trophoblast invasion.     

Human trophoblast cells in culture express an unusual major histocompatibility complex class I-like antigen

We present evidence that the trophoblast cells obtained from first trimester placentae by a culture method developed in our laboratory express a class I-like HLA antigen that is only sparsely distributed on the cell surface, lacks classical polymorphic determinants, and consists of heavy chains of lower molecular weight than those of classical HLA in association with beta 2-microglobulin (beta 2M). The latter two features are in general agreement with a previous report describing the nature of the HLA molecule on trophoblast disaggregated from term amniochorion. These cultured trophoblast cells could be useful for molecular studies of the unusual class I antigen, as well as for other in vitro experiments designed to mimic the in vivo local trophoblast-uterine interactions.     

二氢杨梅素对绒毛膜癌细胞增殖和迁移能力的影响

目的 探讨二氢杨梅素（DMY）对绒毛膜癌（绒癌）JEG-3及JAR细胞增殖和迁移能力的影响。 方法 MTT法检测不同浓度的二氢杨梅素(0 mg/L, 20 mg/L, 40 mg/L, 60 mg/L, 80 mg/L)作用一定时间后,对绒癌JEG-3和JAR细胞增殖能力的影响;细胞划痕实验和Transwell法检测不同浓度二氢杨梅素(0 mg/L, 40 mg/L, 60 mg/L, 80 mg/L)分别作用绒癌JEG-3细胞及JAR细胞一定时间后,对其迁移能力的影响;Real-time PCR和Western blotting方法分别检测不同浓度二氢杨梅素(0 mg/L, 40 mg/L, 60 mg/L, 80 mg/L)作用绒癌JEG-3及JAR细胞后,基质金属蛋白酶2（MMP-2）mRNA和蛋白表达水平的影响。 结果 不同浓度二氢杨梅素作用绒癌JEG-3和JAR细胞24 h和48 h后,随着二氢杨梅素浓度增加,对JEG-3和JAR细胞增殖抑制作用增强（P＜0.05）。二氢杨梅素作用绒癌JEG-3及JAR细胞后,显著抑制细胞迁移能力,且具有浓度依赖性（P＜0.05）。不同浓度二氢杨梅素作用JEG-3和JAR细胞后,MMP-2 的mRNA和蛋白表达水平明显下降（P＜0.05）。 结论 二氢杨梅素能够抑制JEG-3及JAR细胞的增殖能力且具有浓度依赖性,同时二氢杨梅素可能通过下调绒癌JEG-3及JAR细胞中MMP-2 mRNA和蛋白的表达,抑制绒癌细胞的侵袭迁移。     

The synthesis and expression of HLA-A and -B antigens in Xenopus laevis oocytes

Purified mRNA's encoding the HLA-A and -B antigen heavy chains or beta 2-microglobulin were prepared from human B lymphoid cells by positive hybridization selection procedures. The role of chain association in the biosynthesis and intracellular transport of HLA-A and -B antigens was investigated by injecting these mRNA species into Xenopus laevis oocytes and following the fates of the translated products by immunoprecipitation. When mRNA encoding beta 2-microglobulin from the B lymphoblastoid cell line MST was coinjected with mRNA encoding the HLA-A and -B antigen heavy chains from the Burkitt lymphoma cell line Daudi, fully assembled class I antigens were detected using the monoclonal antibody W6/32. This result suggested that there may be no defect in the mRNA encoding Daudi HLA-A and -B antigen heavy chains. When the state of maturity of the N-linked glycan units on these class I antigen heavy chains was assessed, they were found to have undergone some processing. In contrast, when mRNA encoding immunoglobulin M (IgM) was injected into oocytes, the glycan units of the IgM heavy chains were found to be in the unprocessed (high mannose) form. This result shows that Xenopus oocytes can process some eukaryotic glycoproteins of exogenous origin.     

Cytogenetic and DNA-fingerprint characterization of choriocarcinoma cell lines and a trophoblast/choriocarcinoma cell hybrid

We report the successful fusion of human choriocarcinoma cells with normal human trophoblast cells to a choriocarcinoma/trophoblast hybrid. The hybrid cells ACH1P were derived from fusion of primary male trophoblast cells with the HGPRT-defective choriocarcinoma cell line AC1-1. The karyotypes of the parental choriocarcinoma cell line JEG-3, its HGPRT-defective mutant clones AC1-1, AC1-5, and AC1-9, and the choriocarcinoma/trophoblast hybrid ACH1P are presented, together with a detailed characterization of the AC1-specific chromosomal marker add(X)(q26) using conventional cytogenetic banding techniques and multiplex-fluorescence in situ hybridization (M-FISH). To our knowledge, this is the first report of a stably proliferating human cell hybrid of trophoblastic origin, providing a unique cell culture model to study trophoblast-related invasion and its underlying genetic mechanisms.     

Expression of functional chemokine receptors of human placental cells

PROBLEM: Chemokine receptors of placental trophoblasts possibly act as co-receptors or alternative receptors of maternal fetal infection by HIV. To clarify their possible expression and the physiological roles of chemokines on human placentae, we studied chemokine chemokine receptor expression and the effects of exogenous chemokines on choriocarcinoma cell lines. MATERIALS AND METHODS: Placental samples were obtained from 13 placentae of various gestational ages. Villous tissue was mechanically dissected from samples. Trophoblasts were enriched by anti-human chorionic gonadotropin (hCG)-coated magnetic beads. Human choriocarcinoma cell lines (JAR, BeWo, JEG-3) were maintained in RPMI 1640 media supplemented with 10% FCS. Expression of chemokine receptors was studied by RT-PCR. The effects of MIP-1alpha, RANTES, MCP-1 on hCG production were estimated by EIA. Effects of chemokines on proliferation of choriocarcinoma cell lines were examined by MTT assay. RESULTS: We observed mRNA expression of CCR-1, 2, 3, 4, 5 and CXCR-1, 2, 4 in 1st trimester placental villi, CCR-I, 2, 4 and CXCR-1, 2. 4 in 2nd trimester placental villi, CCR-1, 2, 4 and CXCR-4 in 3rd trimester placental villi. Using MACS enriched trophoblasts, we observed identical results. A choriocarcinoma cell line BeWo expressed CCR-1, 3, 4 and CXCR-1, 2, 4 while JEG-3 and JAR expressed CCR-1, 3, 4, 5 and CXCR-1, 2, 4. Expression of the CCR-5 and CXCR-4 protein in choriocarcinoma cell lines and MACS-enriched trophoblats were confirmed by flow cytometry. Chemokine MCP-3, MIP-1alpha, RANTES mRNA were expressed by the 1st, 2nd and 3rd trimester placental samples and the three choriocarcinoma cell lines examined. MCP-1 was expressed by 1st and 2nd trimester placental villi. Administration of chemokines up-regulated proliferation (10(-1) - 10 ng/mL) and hCG production (10(-1) - 10(-2)ng/ mL) of the three choriocarcinoma cell lines examined. CONCLUSIONS: Our results suggest possible roles of chemokines/chemokine receptors on placental physiology and their involvement in HIV transmission as alternative receptors.     

Effects of Tumor Necrosis Factor-Alpha on Human Trophoblast Cell Adhesion and Motility

PROBLEM: Adhesive interaction between trophoblast cells and uterine endometrial basement membrane is one of the critical processes in embryo implantation. This interaction is directly or indirectly regulated by hormones, growth factors, and cytokines. Since tumor necrosis factor-alpha (TNF-α) is synthesized by both decidual and trophoblast cells, we hypothesized that TNF-α may play a regulatory role in trophoblast cell invasion. To test this hypothesis, we have used in vitro models to determine the effect of TNF-α on human trophoblast cell adhesion and motility, two major steps in trophoblast invasion. METHODS: The effect of TNF-α on the motility of extended-lifespan first trimester trophoblasts (HTR) and JEG-3 choriocarcinoma cells was tested using the phagokinetic track motility assay. An in vitro adhesion assay was used to determine the effect of TNF-α on the adhesion of HTR and JEG-3 cells to laminin, a major basement membrane component. In addition, the effect of TNF-α on the surface expression of the laminin receptor β1 integrin subunit was examined using flow cytometry. RESULTS: HTR or JEG-3 cells were strongly adherent to laminin which was not significantly altered by TNF-α treatment. We also measured the effect of TNF-α on the surface expression of β1 integrin on HTR and JEG-3 cells; no difference was observed between control and treatment groups. Interestingly, the motility of both HTR and choriocarcinoma JEG-3 cells was significantly inhibited by TNF-α. CONCLUSIONS: The role of TNF-α in human embryo implantation is currently unknown. Our data demonstrate that TNF-α does not alter trophoblast cell adhesion to laminin, but significantly inhibits trophoblast cell motility in vitro, suggesting that TNF-α may play a regulatory role in trophoblast cell invasion.     

Interleukin-17 Increased Progesterone Secretion by JEG-3 Human Choriocarcinoma Cells

Problem  JEG-3 choriocarcinoma cell line has previously been reported to express a receptor for interleukin (IL)-17. The involvement of IL-17 in the production of progesterone and human chorionic gonadotropin by placental trophoblast has not been investigated.
Method of study  The present study investigated the in vitro effect of IL-17 on progesterone and human chorionic gonadotropin (hCG) secretion by JEG-3 cells. Both hormones were quantified using enzyme-linked immunosorbent assays.
Results  The results showed that IL-17 significantly increased progesterone secretion at 6 ( P  < 0.001) and 24 ( P  < 0.01) hr, while this cytokine had no effect on hCG secretion.
Conclusion  Interleukin-17 may regulate the function of JEG-3 cells through increased progesterone secretion.