Trophoblast Markers




Trophoblasts (from Greek threphein: to feed) are cells forming the outer layer of a blastocyst which provides nutrients to the embryo and develop into a large part of the placenta. They are formed during the first stage of pregnancy and are the first cells to differentiate from the fertilized egg.






  • applicable as a positive marker for the characterization of all subtypes of trophoblast and for trophoblast cell lines. PMID: 11504532


  • The IPL and p57(KIP2)/CDKN1C genes are closely linked and coordinately imprinted, and immunostaining showed that their protein products are co-expressed in villous cytotrophoblast. PMID: 13129680



  • found to be expressed on the majority of EVT, is an extravillous trophoblast marker. PMID: 12771237


  • greater pancytokeratin immunofluorescence is observed in extravillous cytotrophoblast cells as compared with villous trophoblast. The most invasive population of cells of the trophoblast lineage (the extravillous trophoblast) exhibits a significant reduction in cytokeratin immunofluorescence when comparisons of healthy and pre-eclamptic pregnancies are made. PMID: 15287017

  • a highly reliable marker for cells of the trophoblast lineage in vitro, trophoblasts should be identified by the presence of cytokeratin 7 in preference to cytokeratin 8/18. PMID: 10527816

  • Application of immunohistochemical staining for cytokeratin allowed proper identification of trophoblast. PMID: 8906606

  • the different populations of human placental trophoblast express cytokeratins in developmental, differentiative, and functional specific patterns. These findings can be useful to distinguish and classify the various trophoblastic populations and provide a foundation for studying pathological aspects of the trophoblast. PMID: 7539466

Cytokeratin-7 (CK7)

  • an accurate intracellular marker with which to assess the purity of human placental villous trophoblast cells by flow cytometry. PMID: 15087219


  • initially expressed in ectoplacental cone cells and chorionic plate, and later in the labyrinthine trophoblast of the chorioallantoic placenta. PMID: 9874789


  • the extra-villous trophoblast marker and could be used as a specific probe for extra-villous trophoblast in decidual tissue. PMID: 3301747

Gcm1 (glial cells missing 1)

  • a subset of trophoblast cells in the basal layer of the chorion that express the Gcm1 transcription factor. PMID: 16916377

  • a marker of differentiated labyrinthine trophoblasts. PMID: 16433625

  • GCM1 protein expression studies demonstrated that the transcription factor was present mainly within the nuclei of a subset of cytotrophoblast cells, consistent with its role as a transcription factor. PMID: 15135239

  • encoding the transcription factor glial cells missing-1 (Gcm1), is expressed in small clusters of chorionic trophoblast cells at the flat chorionic plate stage and at sites of chorioallantoic folding and extension when morphogenesis begins. PMID: 10888880


  • a trophoblast marker which reacts with placental-type alkaline phosphatase (PLAP) associated with the cell-membrane of the syncytiotrophoblast. PMID: 2590397

  • a trophoblast-specific marker. PMID: 3500181

  • reacting against a specific antigen present on the surface of foetal trophoblastic cells. PMID: 3510966

  • identifies a trophoblast-specific cell-surface antigen and strongly stained both placental villous trophoblast and the cytotrophoblastic layer of amniochorion. PMID: 6312818


  • H315 and H316 showed comparable staining of placental villous syncytiotrophoblast and cytotrophoblast and were also able to distinguish subpopulations of nonvillous trophoblast in the placental bed, including perivascular and endovascular trophoblastic cells as well as cytotrophoblastic elements within the decidua and myometrium. PMID: 6197884

  • reacted predominantly with normal placental trophoblast and with lymphocytic cells, as well as with most transformed or neoplastic cultured cell lines. PMID: 7118296


  • trophoblast-specific transcription factor. PMID: 12842421

  • trophoblast differentiation marker. PMID: 16885536, PMID: 10611232

  • the marker gene of trophoblast lineage. PMID: 15882982

  • detectable in trophoblastic tumour cells suggesting an equivalent role in trophoblast differentiation. PMID: 12527202

  • plays an important role in the differentiation of the amniotic membrane and the pre-implanting trophoblast. PMID: 11802795

  • Hand1 mRNA, however, was abundantly expressed in cytotrophoblastic Jeg-3 and BeWo cells, suggesting that Hand1 could be required for early trophoblast differentiation. PMID: 9931445

  • expression is restricted to placental trophoblast cells and later to embryonic cardiac and neural crest cells. PMID: 9500551


  • encodes a transcription factor playing a role in the development of the trophoblast. PMID: 9610003

hCG (human chorionic gonadotropin)

  • a hormone synthesized by trophoblast cells. PMID: 15570553

  • marker for the differentiation process of cytotrophoblast cells. PMID: 15852231

  • marker for the differentiation process of trophoblast cells to syncytial trophoblasts. PMID: 12942243, PMID: 12820356

  • a placental hormone and marker for the differentiation process of cytotrophoblast cells to syncytial trophoblasts. PMID: 12820352

hCG-beta (Human chorionic gonadotrophin beta)

  • a trophoblast marker, is expressed in human 8-cell embryos derived from tripronucleate zygotes. PMID: 2460490


  • HLA-G protein expression in different stages of pregnancy and different trophoblasts may be related to the controlled invasion of the trophoblast. PMID: 16354612

  • a nonclassical MHC class I antigen that has been shown to be a specific marker for normal intermediate trophoblast (IT), can serve as a useful marker in the differential diagnosis of these lesions. PMID: 12131159

  • HLA-G expression in extravillous trophoblasts is induced in an autonomous manner, independently of embryonic development, and may be an integral part of placental development allowing its tolerance from maternal immune system. PMID: 11137214

  • It has a tissue-specific expression in trophoblast, where the products of HLA-A, -B and -C classical genes are absent. PMID: 7583772

  • HLA-A,B,C was employed to discriminate intermediate trophoblasts (Its) from cytotrophoblasts (CTs). PMID: 2584815

hPL (human placental lactogen)

  • marker for the differentiation process of trophoblast cells to syncytial trophoblasts. PMID: 12942243


  • expressed at a high level in undifferentiated trophoblast stem cells and then down-regulated during early differentiation, and is thought to be a key regulator in the trophoblast giant-cell differentiation pathway. PMID: 16638616



  • plays an important role in trophoblast and chondrogenic differentiation by negatively regulating a subset of lineage-restricted bHLH proteins. PMID: 9799236

Inhibin A

  • Maternal serum inhibin A levels are a marker of a viable trophoblast in incomplete and complete miscarriage. PMID: 12590643


  • alpha5 integrin mediates binding of human trophoblasts to fibronectin and is implicated in the regulation of trophoblast migration. PMID: 15846213

  • interaction with fibronectin through integrin alpha5 plays an important role in human extravillous trophoblast invasion. PMID: 17027088

  • Integrins display dynamic temporal and spatial patterns of expression by the trophoblast cells during early pregnancy in humans. PMID: 15255377

  • Direct contact between trophoblasts and endothelial cells increases the expression of trophoblast beta1 integrin. PMID: 15189562

  • integrin, alphaIIbbeta3, plays a key role in trophoblast adhesion to fibronectin during mouse peri-implantation development. In vivo, alphaIIb was highly expressed by invasive trophoblast cells in the ectoplacental cone and trophoblast giant cells of the parietal yolk sac. PMID: 15031111

  • the alpha 7 beta 1 integrin is expressed by trophoblast cells and acts as receptor for several isoforms of laminin during implantation. PMID: 11784026

  • Villous trophoblast from first trimester and term placenta expresses the integrin subunits alpha 6 and beta 4, as monitored by immunohistochemistry. PMID: 7685095

  • the expression of a alpha 5 integrin subunit on cytotrophoblastic cell surfaces is correlated with the appearance of an invasive phenotype. PMID: 8288018


  • induced coincidentally with the transition to the endocycle in trophoblast giant cells, is stable when ectopically expressed in proliferating trophoblast cells. PMID: 10712518

  • The IPL and p57(KIP2)/CDKN1C genes are closely linked and coordinately imprinted, and immunostaining showed that their protein products are co-expressed in villous cytotrophoblast. However, other cell types, including extravillous cytotrophoblast and cells in various non-placental tissues, expressed p57(KIP2), but not IPL. PMID: 13129680



  • the spongiotrophoblast marker. PMID: 16966370, PMID: 15901283

  • immunoreactive Mash-2 protein was localized predominantly to the cytoplasm of human cytotrophoblasts. PMID: 12917334

  • trophoblast-specific transcription factors. PMID: 12842421

  • may serve as a hypoxia-induced transcription factor that prevents differentiation to syncytiotrophoblast and aromatase induction in human trophoblast cultured under low O2 conditions. PMID: 11043580

  • Mash-2 expression begins during preimplantation development, but is restricted to trophoblasts after the blastocyst stage. Within the trophoblast lineage, Mash-2 transcripts are first expressed in the ectoplacental cone and chorion, but not in terminally differentiated trophoblast giant cells. After day 8.5 of gestation, Mash-2 expression becomes further restricted to focal sites within the spongiotrophoblast and labyrinth. PMID: 9291577

  • a mammalian member of the achaete-scute family which encodes basic-helix-loop-helix transcription factors and is strongly expressed in the extraembryonic trophoblast lineage. PMID: 8090202


  • for trophoblast cell identification, is a trophoblast marker. PMID: 12848643

  • identified, as expected, syncytial giant cells and mononuclear trophoblasts within the placental bed and glandular epithelial cells throughout the uterus, but also cross-react with epitopes expressed in cells other than giant trophoblastic cells and mononuclear trophoblasts in the uterus and, thus, caution has to be used when such antibodies are used for the diagnostic characterization of tissues related to the placental bed. PMID: 8575730


  • NDOG1 stained chorionic syncytiotrophoblast but not villous cytotrophoblast and also did not react with any cytotrophoblastic elements in the placental bed. NDOG1 distinguished these different subpopulations of trophoblast as early as 13 to 15 days after ovulation. PMID: 6197884


  • reacted only with trophoblast of placental chorionic villi and did not react with any nonvillous cytotrophoblast population. PMID: 6312818

PAI-1 (plasminogen activator inhibitor-1)

  • an immunocytochemical marker of invading trophoblasts. PMID: 2473276

  • plays a key role in the regulation of fibrinolysis and cellular invasion by virtue of suppression of plasminogen activator function. PMID: 12398812

  • present in villous syncytiotrophoblasts and co-localized focally with fibrin-type fibrinoid on the surface of the chorionic villi. Basal plate and placental bed extravillous interstitial trophoblasts, as well as vascular trophoblasts, were also PAI-1 positive. PAI-1 defines specific extravillous invasive trophoblasts within the maternal decidua. PMID: 11095924


  • expressed in term placental villi, primarily in the trophoblast layer. Using quantitative PCR we found that the expression of PHLDA2 gradually declined during differentiation of primary term human trophoblasts. PMID: 16584773

Placental Lactogen (PL-1, PL-2)

  • a trophoblast cell differentiation marker. PMID: 15685636

  • Trophoblast giant cells release two types of PLs in vitro; a high-molecular-weight lactogen, PL-1, and a low-molecular-weight lactogen, PL-2. PMID: 3972167


  • PLP-A was expressed in both trophoblast giant cells and spongiotrophoblast cells, whereas PLP-B was expressed in decidual and spongiotrophoblast cells. PMID: 9472921

  • PLP-L and PLP-M are most highly expressed in invasive trophoblast cells lining the central placental vessel as markers of invasive trophoblasts in the rat. PMID: 10906059

  • Expression of PLP-N mRNA was restricted to migratory trophoblast cells. PMID: 14656203

  • PLP-A, PLP-L and PLP-M are synthesized by both interstitial and endovascular rat trophoblast cells. PMID: 12885563

  • PLP-A is a novel pregnancy- and trophoblast cell-specific cytokine. PMID: 12850282

  • In the mouse, PLF-RP was expressed in the trophoblast giant cell layer of the midgestation chorioallantoic and choriovitelline placentas and, during later gestation, in the trophoblast giant cell and spongiotrophoblast layers within the junctional zone of the mouse chorioallantoic placenta. In the mouse, PLP-F is an exclusive product of the spongiotrophoblast layer, whereas in the rat, trophoblast giant cells were found to be the major source of PLP-F, with a lesser contribution from spongiotrophoblast cells late in gestation. PMID: 10657001

  • PLP-A was specifically localized to giant and spongiotrophoblast cells of the junctional zone. PMID: 2667962

  • PLP-C is a major secretory protein produced by spongiotrophoblast cells during the second half of gestation. PMID: 2036977

  • PLP-C mRNA was specifically expressed by spongiotrophoblast cells and some trophoblast giant cells in the junctional zone region of rat chorioallantoic placenta. PMID: 1744098

  • PLP-A, PLP-B and PLP-C are expressed in distinct cell- and temporal-specific patterns and can be used to monitor the state of differentiation of rat trophoblast cells. PMID: 8290493

  • PLP-D mRNA was specifically expressed in spongiotrophoblast cells and trophoblast giant cells of the placental junctional zone. PMID: 8756556

  • PLP-Cv is a unique gene structure, and displaying a trophoblast-specific pattern of transcriptional activation. PMID: 8895375

  • Expression of PLP-E is restricted to the trophoblast giant cells, whereas PLP-F is synthesized only in the spongiotrophoblasts. PMID: 9389541


  • an excellent marker for trophoblast uninucleate cells from placenta of sheep at the later stages of pregnancy. PMID: 1692053


  • a trophoblast-specific beta 1-glycoprotein. PMID: 2450546, PMID: 3675636, PMID: 2422727

  • In syncytiotrophoblast, SP-1 was expressed in normal pregnancy and unexpressed in spontaneous abortion. PMID: 9589941

  • HCG and SP-1 are equally well suited for the serial evaluation of trophoblast function in early pregnancy. PMID: 6984404

  • a good, additional parameter for the assessment of the trophoblast function. PMID: 94488

TA1/TA2 (trophoblast antigens)


  • the chorionic trophoblast marker. PMID: 15987772

  • expressed at low levels in the embryo but at high levels in the labyrinthine trophoblast cells of the placenta, plays a critical role in the signal transduction processes required for normal vascularization of the placenta. PMID: 9806910

Troma 1 and CAM 5.2


  • Markers for human placental trophoblasts in two-dimensional gel electrophoresis. PMID: 1700776

  • Detection of both progesterone receptors and laminin, or type IV collagen, excluded fibroblast contamination and could then be useful for quick identification of cultured trophoblast cells. PMID: 2572485

  • Comparative study of placental protein 19, human chorionic gonadotrophin and pregnancy-specific beta 1-glycoprotein as immunohistochemical markers for extravillous trophoblast in pregnancy and trophoblastic disease. PMID: 2559069