Identification of extra-villous trophoblast cells in human decidua using an apparently unique murine monoclonal antibody to trophoblast

Obstetric outcomes in thyroid cancer survivors: A retrospective cohort study

OBJECTIVE

To investigate whether thyroid cancer survivors would have increased risks of adverse obstetric outcomes.

METHODS

Data from 154 women with a history of thyroid cancer who had a live birth at Peking University Third Hospital from January 2012 to December 2019 were collected. The control group consisted of 308 women without any thyroid disease or malignant tumor. Age and year of delivery were matched between the two groups.

RESULTS

Serum levels of thyroid stimulating hormone and free thyroxine were significantly lower and higher in thyroid cancer patients, respectively (P < 0.001). After adjusting for age, pre-pregnancy body mass index, pre-pregnancy hypertension, pre-pregnancy diabetes mellitus, previous cesarean section, and conception by in vitro fertilization/intracytoplasmic injection, adverse obstetric outcomes including preterm birth (odds ratio [OR] 0.73, 95% confidence interval [CI] 0.32-1.67), low birth weight infant (OR 1.05, 95% CI 0.44-2.50), gestational diabetes mellitus (OR 0.86, 95% CI 0.54-1.39), and pre-eclampsia (OR 1.11, 95% CI 0.34-3.57) showed no differences between thyroid cancer survivors and the control group. However, pregnant women with a history of thyroid cancer had a higher risk of abnormally invasive placentation (OR 10.57, 95% CI 1.22-91.97, P = 0.032).

CONCLUSION

Although the thyroid function status of thyroid cancer patients was different from that of pregnant women without any thyroid disease or malignancy, they would not be at a higher risk of most adverse obstetric outcomes except for abnormally invasive placentation.

Decidua parietalis-derived mesenchymal stromal cells reside in a vascular niche within the choriodecidua

Mesenchymal stromal cells (MSCs) from gestational tissues represent promising cell populations with stem cell-like properties for use in regenerative medicine. Previously, we reported that MSCs in the chorionic villi of the human placenta reside in a vascular niche. However, the niche(s) in which MSCs reside in the fetal membranes, another rich source of MSCs, remains to be determined. The cell surface markers STRO-1 and 3G5 were previously employed to identify niches in a variety of tissues and here we use these markers to report the location of the MSC niche in the human decidua parietalis. The cultured decidua parietalis MSCs (DPMSCs) isolated from the choriodecidua component of the fetal membranes possessed stem cell-like properties such as adherence to plastic, colony forming ability, and multipotent differentiation potential. Fluorescence in situ hybridization analysis showed cultured DPMSCs were of maternal origin. Immunocytochemistry demonstrated that cultured DPMSCs stained positively with stem cell surface markers 3G5, CD105, CD106, STRO-1, CD146, CD49a, and α-SMA but were negative for hematopoietic markers (CD117, CD34) and vascular markers (CD34, von Willebrand factor [vWF]). Immunohistochemistry with antibodies to stem cell surface markers and the endothelial markers on term fetal membranes revealed a vascular niche for DPMSCs, which was confirmed by immunofluorescence analysis. Both STRO-1 and vWF fluorescence signals showed substantial overlap, while CD146 and vWF signals showed partial overlap. These observations were consistent with a vascular niche.

A novel basal lamina matrix of the stratified epithelium of the ovarian follicle

Basal laminas are important sheets of specialized extracellular matrix that underlie and surround groups of cells, such as epithelia or endothelia, enabling the cells to orientate their basal/apical polarity and creating a microenvironment for them. Basal laminas can also individually encapsulate whole cells, such as muscle cells, thereby forming a microenvironment but not polarizing the enclosed cells. Other mesenchymal or stromal cells exist with no basal lamina. In the course of studying the bovine follicular basal lamina which underlies the multilayered epithelium of the ovarian follicle, we identified a developmentally regulated novel extracellular matrix (which we call focimatrix for focal intra-epithelial matrix). Focimatrix is composed of basal lamina-like material deposited as plaques or aggregates between the multilayers of the epithelial granulosa cells. The focimatrix does not encapsulate individual or groups of cells and therefore does not form a microenvironment for them. Focimatrix contains collagen type IV subunits alpha1 and alpha2 (but not alpha3-alpha6), and laminin chains alpha1, beta2 and gamma1 (but not alpha2 or beta1), and nidogen-1 and perlecan (but not versican). The amount of focimatrix increases with increasing follicular size, and its appearance precedes the expression by granulosa cells of the enzymes for steroid hormone synthesis, cholesterol side-chain cleavage cytochrome P450 (SCC) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD), in the days preceding ovulation. The expression in granulosa cells of two components examined, nidogen-1 and perlecan, also increases substantially when follicles enlarge to a sufficient size capable of ovulating. Following ovulation the follicular basal lamina is degraded, and presumably focimatrix is too since it is not detected in corpora lutea that develop from the ovulating follicles. During this development the granulosa cells undergo an epithelial-mesenchymal transition (EMT) into luteal cells following ovulation, and substantially increase their expression of steroidogenic enzymes in the process. During EMT epithelial cells lose polarity. Since focimatrix exists on more than one side of the granulosa cells, we propose that it disrupts the polarity induced by the follicular basal lamina in the lead up to ovulation. Hence focimatrix maybe a key part of the follicular/luteal EMT.

Cholesterol side-chain cleavage cytochrome P450 and 3beta-hydroxysteroid dehydrogenase expression and the concentrations of steroid hormones in the follicular fluids of different phenotypes of healthy and atretic bovine ovarian follicles

Bovine ovarian antral follicles exhibit either one or the other of two patterns of granulosa cell death in atresia. Death can commence either from the antrum and progress toward the basal lamina (antral atresia) or the converse (basal atresia). In basal atresia, the remaining live antrally situated cells appeared to continue maturing. Beyond that, little is known about these distinct patterns of atresia. Healthy (nonatretic) follicles also exhibit either one or the other of two patterns of granulosa cell shape, follicular basal lamina ultrastructure or location of younger cells within the membrana granulosa. To examine these different phenotypes, the expression of the steroidogenic enzymes cholesterol side-chain cleavage cytochrome P450 (SCC) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in granulosa cells and concentrations of steroid hormones in follicular fluid were measured in individual histologically classified bovine antral follicles. Healthy follicles first expressed SCC and 3beta-HSD in granulosa cells only when the follicles reached an approximate threshold of 10 mm in diameter. The pattern of expression in antral atretic follicles was the same as healthy follicles. Basal atretic follicles were all <5 mm. In these, the surviving antral granulosa cells expressed SCC and 3beta-HSD. In examining follicles of 3-5 mm, basal atretic follicles were found to have substantially elevated progesterone (P < 0.001) and decreased androstenedione and testosterone compared to healthy and antral atretic follicles. Estradiol was highest in the large healthy follicles, lower in the small healthy follicles, lower still in the antral atretic follicles, and lowest in the basal atretic follicles. Our findings have two major implications. First, the traditional method of identifying atretic follicles by measurement of steroid hormone concentrations may be less valid with small bovine follicles. Second, features of the two forms of follicular atresia are so different as to imply different mechanisms of initiation and regulation.

Dynamic changes in the expression of relaxin-like factor (INSL3), cholesterol side-chain cleavage cytochrome p450, and 3beta-hydroxysteroid dehydrogenase in bovine ovarian follicles during growth and atresia

Relaxin-like factor (RLF) is a new member of the insulin-relaxin gene family known to be expressed in the ovarian follicular thecal cells of ruminants. To investigate the pattern of RLF expression in development and atresia of bovine follicles, antisera were raised in rats and rabbits to recombinantly expressed bovine pro-RLF and to chemically synthesized ovine RLF B chain, respectively. On dot blotting analysis, the rat antiserum bound to pro-RLF and less strongly to a synthetic mature ovine RLF lacking the C-domain, whereas the rabbit antiserum bound the mature form of ovine RLF. These antisera were used to immunostain bovine ovarian follicles of differing sizes and stages of health and atresia. 3beta-Hydroxysteroid dehydrogenase was colocalized with pro-RLF (n = 86 follicles), and cholesterol side-chain cleavage cytochrome P450 was localized in another section of many of the same follicles (n = 66). Not all follicles expressed pro-RLF in the theca interna, so the results are presented as the proportion of follicles expressing pro-RLF. Both mature and pro-RLF were immunolocalized to steroidogenic thecal cells of healthy follicles. As follicles enlarged to >5 mm, the proportion expressing pro-RLF declined (19/19 for <5 mm and 18/26 for >6 mm). Atresia was divided into antral (antral granulosa cells dying first) or basal (basal cells dying first) and further divided into early, middle, and late. For antral atresia of small follicles (2-5 mm), no decline in the proportion expressing pro-RLF was observed (early 6/6, middle 2/2) until the late stages (1/4). For basal atresia, which only occurs in small follicles (2-5 mm), the proportion expressing pro-RLF declined in the middle (2/5) and late (0/8) stages. In larger follicles (>6 to <10 mm), the proportion expressing pro-RLF also declined with atresia (1/13). These declines in RLF expression with atresia or increasing size were not accompanied by a decline in the expression of steroidogenic enzymes in the theca interna. A significant (P < 0.001) inverse relationship in the expression of pro-RLF and 3beta-hydroxysteroid dehydrogenase in the membrana granulosa was observed. We conclude that the expression of pro-RLF in the theca interna is switched off as follicles enlarge or enter atresia, whereas the expression of steroidogenic enzymes is maintained in the theca interna.

Inconsistency of fetal trophoblast cells in first trimester maternal peripheral blood prevents non-invasive fetal testing using this cell target

We have investigated whether maternal peripheral blood from the first trimester of pregnancy is a reliable source of identifiable trophoblast cells. The cells were enriched from 30 ml of venous blood, with multiple antibodies shown previously to enrich trophoblasts and a new cocktail based on known trophoblast surface features. Three different magnetic solid phases were tested to enrich trophoblasts, and both positive and negative cell enrichment strategies were examined. The cells were identified as trophoblast by morphology coupled with immunocytochemistry to co-localize cytokeratin with one of three IGF-II, PAI-1 or hPLH proteins or by in-situ hybridization with a mixture of 50 oligos directed to eight different expressed genes, alpha-HCG, IGF-II, PAI-1, HASH2, hPLH, p57(KIP2), PP5, H-19. While these tools worked beautifully in chorionic villi cell/sprout preparations and tissue sections, we could not detect and identify any trophoblasts in maternal peripheral blood even if the maternal peripheral blood was drawn 5-20 min following termination of pregnancy or from individuals maintaining the pregnancy. Based on our own experience and that of some reports in the literature, trophoblasts do not appear to be a viable candidate for fetal screening using maternal peripheral blood as the source. It is important to note that while trophoblast deportation is a biological phenomenon that has been described repeatable, they do not provide a means to perform prenatal genetic diagnosis.

A monoclonal antibody to human placental lactogen hormone facilitates isolation of fetal cells from maternal blood in a model system

A cocktail of trophoblast-reactive monoclonal antibodies (MAbs) is required for efficient isolation of trophoblasts from maternal blood. A modified antibody screening procedure was used to identify a clone, in a COS cell placental cDNA expression library, that expressed the gene product recognized by MAb FDO202N. The antigen recognised by MAb FDO202N was identified as human placental lactogen (hPL) hormone. hPL hormone is secreted into the maternal blood by trophoblasts at high levels during pregnancy. Immunohistochemical localization of hPL hormone was consistent with expression in the syncytiotrophoblast and extravillous cytotrophoblast. A model system was used where known numbers of syncytiotrophoblast sprouts were seeded into saline or maternal blood, bound by trophoblast-specific MAbs, recovered magnetically, and then counted. MAb FDO202N was shown to facilitate the efficient recovery of trophoblast sprouts from saline and maternal blood.

Generation and characterization of monoclonal antibodies specific to surface antigens of human trophoblast cells

PROBLEM

To generate and utilize specific monoclonal antibodies for routine fetal cell isolation from the maternal circulation.

METHODS

Monoclonal antibodies specific to human trophoblast cell surface antigens were generated and characterized. After cell fusion, antibodies secreted by hybridomas were screened by enzyme-linked immunosorbent assay and immunohistochemical assays.

RESULTS

By using cultured BeWo choriocarcinoma cells or the membrane fraction of human placenta as the immunogen, seven (BW-108, 110, 123, 124, HP-15, 16 and 17) antibodies specific to the surface antigens of trophoblast were produced. They were shown to have little cross-reactivity to other human tissues. Among the antibodies raised against human sperm, HSA-10 was also found to cross-react with human trophoblast, but not detected in other tissues. When immobilized to magnetic beads, these antibodies were shown to react only with BeWo cells in suspension, but not blood cells and ovarian carcinoma cell line, OC-3-VGH.

CONCLUSION

Therefore, these antibodies may have potential application in fetal trophoblast cell isolation from the maternal circulation for prenatal genetic diagnosis.

A morphologic study of trophoblast isolated from peripheral blood of pregnant women

OBJECTIVE

Our purpose was to evaluate the morphologic characteristics of cells separated from peripheral maternal blood with immunomagnetic beads coated with trophoblast-reactive monoclonal antibodies of restricted specificity.

STUDY DESIGN

Blood samples were collected from 14 pregnant women at 9 to 12 or 16 to 18 weeks' gestation. Immunomagnetic beads coated with trophoblast-reactive monoclonal antibodies were used to isolate cells from the blood. The isolated cells were then fixed, embedded, and sectioned to enable morphologic identification.

RESULTS

Multinucleate cells identical to syncytiotrophoblast sprouts were identified in 12 of 14 samples.

CONCLUSION

Multinucleate syncytiotrophoblast can be isolated from the peripheral blood of normal pregnant women in both the first and second trimesters of pregnancy. The isolated trophoblast may allow prenatal genetic diagnosis by a noninvasive technique.

Isolation of fetal trophoblast cells from peripheral blood of pregnant women

Fetal trophoblast cells were isolated from maternal peripheral blood by means of murine monoclonal antibodies of high specificity and affinity for human syncytiotrophoblast and nonvillous cytotrophoblast cells. The cells were isolated in sufficient numbers to allow polymerase chain reaction (PCR) amplification of the Y-chromosome-specific DNA sequence from the peripheral blood of thirteen pregnant women. The fetal sex predicted by PCR analysis of the isolated trophoblast cells accorded with that ascertained by karyotyping of chorionic villus samples in eleven of twelve women studied in early pregnancy and with the sex of the baby on delivery in one woman studied at 34 weeks' gestation. Isolation of these fetal cells could allow noninvasive diagnosis of a wide range of inherited disorders.

Human placentae: view from an immunological bias

Human placentae form a major part of the interface between maternal and embryonic tissues. Placentae are morphologically complex organs that are lined with a trophoblastic tissue that provides anatomical constraints over which flows maternal blood. Maternal antibodies and immune cells thus contact the lining syncytiotrophoblast, and this paper considers some of the antigens that maternal immune components might encounter. The antigens have been grouped into those of unknown function, major histocompatibility antigens, and antigens of suspected function. The paper also details certain antigens of cytotrophoblasts. We discuss consequences of maternal immune responses to extraembryonic antigens and present evidence for amplification of these responses through the activation of hemostasis and fibrinolysis within the placenta and placental bed.