Lawrence W. Chamley

Antiphospholipid antibodies in pregnancy: prevalence and clinical associations

Objective To determine prevalence, clinical association and predictive power of antiphospholipid antibodies in pregnancy.

A randomized, double-blind, placebo-controlled trial of heparin and aspirin for women with in vitro fertilization implantation failure and antiphospholipid or antinuclear antibodies.

OBJECTIVE To investigate whether heparin and low-dose aspirin increase the pregnancy rate in antiphospholipid antibody or antinuclear antibody-seropositive women with IVF implantation failure. DESIGN A double-blind, randomized, transfer-by-transfer of fresh or cryopreserved embryos, crossover trial.A hospital infertility clinic and associated IVF service. PATIENT(S) Women seropositive for at least one antiphospholipid (APA), antinuclear (ANA), or beta(2) glycoprotein I autoantibody and >or=10 embryos transferred without achieving pregnancy (n = 143). INTERVENTION(S) Subcutaneous unfractionated heparin (5000 IU b.i.d.) and aspirin (100 mg daily) (158 transfers of 296 embryos) or placebo (142 transfers of 259 embryos) from the day of embryo transfer. MAIN OUTCOME MEASURE(S) Fetal heart per embryo transferred (implantation rate). RESULT(S) There was no significant difference in pregnancy rates or implantation rates between treated and placebo cycles; for example, fetal hearts per embryo transferred implantation rates were 6.8% (20/296) and 8.5% (22/259), respectively, and the generalized estimating equation covariate adjusted relative pregnancy rate was 0.65 (95% confidence interval, 0.33-1.28). The implantation rate for seropositive trial participants (42/555, 7.6%) compared favorably with that for IVF implantation-failure patients continuing treatment outside the trial (147/3237, 4.5%). CONCLUSION(S) Heparin and aspirin did not improve pregnancy or implantation rates for APA-positive or ANA-positive patients with IVF implantation failure.

Antiphospholipid antibodies induce a pro-inflammatory response in first trimester trophoblast via the TLR4/MyD88 pathway

Problem  Women with antiphospholipid antibodies (aPL) are at risk for recurrent miscarriage, pre‐eclampsia, and pre‐term labor. aPL target the placenta directly by binding to beta2‐glycoprotein I (β2GPI) expressed on the surface of trophoblast cells. The objective of this study was to determine the effects of aPL on trophoblast function and the mechanisms involved.

Human Placental Mesenchymal Stem Cells (pMSCs) Play a Role as Immune Suppressive Cells by Shifting Macrophage Differentiation from Inflammatory M1 to Anti-inflammatory M2 Macrophages

BackgroundMesenchymal stem cells (MSCs) have a therapeutic potential in tissue repair because of capacity for multipotent differentiation and their ability to modulate the immune response. In this study, we examined the ability of human placental MSCs (pMSCs) to modify the differentiation of human monocytes into macrophages and assessed the influence of pMSCs on important macrophage functions.MethodsWe used GM-CSF to stimulate the differentiation of monocytes into the M1 macrophage pathway and then co-cultured these cells with pMSCs in the early stages of macrophage differentiation. We then evaluated the effect on differentiation by microscopic examination and by quantification of molecules important in the differentiation and immune functions of macrophages using flow cytometry and ELISA. The mechanism by which pMSCs could mediate their effects on macrophage differentiation was also studied.ResultsThe co-culture of pMSCs with monocytes stimulated to follow the inflammatory M1 macrophage differentiation pathway resulted in a shift to anti-inflammatory M2-like macrophage differentiation. This transition was characterized by morphological of changes typical of M2 macrophages, and by changes in cell surface marker expression including CD14, CD36, CD163, CD204, CD206, B7-H4 and CD11b, which are distinctive of M2 macrophages. Co-culture with pMSCs reduced the expression of the costimulatory molecules (CD40, CD80 and CD86) and increased the expression of co-inhibitory molecules (CD273, CD274 and B7-H4) as well as the surface expression of major histocompatibility complex (MHC-II) molecules. Furthermore, the secretion of IL-10 was increased while the secretion of IL-1β, IL-12 (p70) and MIP-1α was decreased; a profile typical of M2 macrophages. Finally, pMSCs induced the phagocytic activity and the phagocytosis of apoptotic cells associated with M2- like macrophages; again a profile typical of M2 macrophages. We found that the immunoregulatory effect of pMSCs on macrophage differentiation was mediated by soluble molecules acting partially via glucocorticoid and progesterone receptors.ConclusionsWe have shown that pMSCs can transition macrophages from an inflammatory M1 into an anti-inflammatory M2 phenotype. Our findings suggest a new immunosuppressive property of pMSCs that may be employed in the resolution of inflammation associated with inflammatory diseases and in tissue repair.

Antibodies to β2 glycoprotein I are associated with in vitro fertilization implantation failure as well as recurrent miscarriage: results of a prevalence study ☆

OBJECTIVE To investigate whether antiphospholipid and related autoantibodies are associated with IVF implantation failure as well as with recurrent spontaneous miscarriage. DESIGN Prevalence study. SETTING University teaching hospital and associated IVF unit. PATIENT(S) Patients with at least three consecutive first-trimester miscarriages (n = 97), patients undergoing IVF who had at least 10 embryos transferred without any resulting clinical pregnancy (n = 105), fertile women (n = 106), and patients newly referred for IVF treatment (n = 52). INTERVENTION(S) Antibodies tested included lupus anticoagulant; immunoglobulin (Ig) G and IgM isotypes of each of anticardiolipin antibody, antiphosphatidylserine, antiphosphatidylethanolamine, and antiphosphatidylinositol; beta2 glycoprotein I antibodies; and antinuclear antibodies. Statistical analysis included chi2 and Fishers exact tests for differences between groups, and multiple linear regression analysis and Spearmans nonparametric tests for relations between results. MAIN OUTCOME MEASURE(S) Seropositivity for autoantibodies tested. RESULT(S) Overall, 84 (23%) of the 360 samples tested positive for at least one autoantibody. Beta2 glycoprotein I IgM antibody and antinuclear antibody were significantly associated with both IVF implantation failure and recurrent miscarriage. CONCLUSION(S) Autoantibodies, particularly beta2 glycoprotein I antibodies and antinuclear antibodies, are associated with IVF implantation failure as well as with recurrent spontaneous abortion, although the mechanism is still unclear. The high seroprevalence of antibodies to beta2 glycoprotein I suggests that it may have an important role in autoimmune reproductive failure that needs to be explored further.

Tumor Necrosis Factor-Alpha, Interleukin-6, and Interleukin-10 Levels are Altered in Preeclampsia: A Systematic Review and Meta-Analysis

Published reports testing the association between cytokine levels and preeclampsia are conflicting. This comprehensive systematic review and meta‐analysis aimed at testing the association between preeclampsia and maternal circulating tumor necrosis factor‐alpha (TNF‐α), interleukin (IL)‐6, and IL‐10.

Antisperm antibodies and conception

Sperm have been known to be antigenic for more than a century. There is a strong body of evidence that in humans and in other species at least some antibodies that bind to sperm antigens can cause infertility. Therefore, these antibodies are of interest today for two practical reasons. Firstly, the association of the antibodies with infertility means that they must be detected and then the couples treated appropriately. Secondly, because these antibodies can induce infertility they have the potential to be developed for contraceptive purposes in humans and also for the control of feral animal populations.

Phagocytosis of Necrotic but Not Apoptotic Trophoblasts Induces Endothelial Cell Activation

It is hypothesized that preeclampsia is caused by factors from the placenta that induce endothelial cell activation. Trophoblasts are cells that may be shed from the placenta, then deported in the maternal blood, and finally become trapped in the pulmonary capillaries. The ultimate fate of deported trophoblasts is unknown, but to prevent clogging of the pulmonary circulation they must be cleared from the capillary beds. We examined the hypothesis that endothelial cells phagocytose deported trophoblasts and also examined the consequent effects of the trophoblasts on endothelial cells. Fluorescently labeled trophoblast–derived choriocarcinoma cells were induced to become apoptotic or necrotic and exposed to endothelial cell monolayers. Confocal microscopy demonstrated uptake of both apoptotic and necrotic trophoblasts, and this phagocytosis could be inhibited by cytochalasin B. Phagocytosis of necrotic but not apoptotic trophoblasts induced increased endothelial intercellular adhesion molecule 1 (ICAM-1) expression, as well as increased adhesion of monocytes to endothelial cell monolayers. Inhibiting the phosphatidylinositol 3-kinase and p38 mitogen-activated protein kinase pathways blocked both expression of ICAM-1 and phagocytosis, whereas inhibition of the P42/44 mitogen-activated protein kinase pathway blocked only ICAM-1 expression. This work suggests that endothelial cells can phagocytose deported trophoblasts and that the mechanism of trophoblast death (apoptotic or necrotic) could have major effects on the maternal vascular response to shed trophoblasts.

Sex of Bovine Embryos May Be Related to Mothers' Preovulatory Follicular Testosterone

Although the sex of the offspring in mammals is commonly viewed as a matter of chance (depending on whether an X or a Y chromosome-bearing spermatozoon reaches the ovum first), evolutionary biologists have shown that offspring sex ratios are often significantly related to maternal dominance, a characteristic that has been shown to be linked to testosterone in female mammals, including humans. Hence, we hypothesized that variations in female testosterone might be related to reproductive mechanisms associated with sex determination, with higher levels of follicular testosterone being associated with a greater likelihood of conceiving a male. To investigate this hypothesis we collected follicular fluid and cumulus-oocyte complexes from bovine antral follicles. Individual matched samples of follicular fluid were assayed for testosterone, whereas the oocytes were matured, fertilized, and cultured in vitro. The resultant embryos were sexed by PCR. The level of testosterone in the follicular fluid was then compared with sex of the embryo (n = 171). Results showed that follicular testosterone levels were significantly higher for subsequently male embryos (Mann-Whitney U = 2823; P [one-tailed] = 0.016). When we excluded embryos from follicles in which the estradiol-to-testosterone ratio was more than 1 (leaving a sample size of 135), the same result held (Mann-Whitney U = 1667; P [one-tailed] = 0.009). Thus, bovine ova that developed in follicular fluid with high concentrations of testosterone in vivo were significantly more likely to be fertilized by Y chromosome-bearing spermatozoa.

Regulated expression of signal transducer and activator of transcription, Stat5, and its enhancement of PRL expression in human endometrial stromal cells in vitro.

Differentiation of human endometrium during the secretory phase of the menstrual cycle is characterized by expression of a variety of genes implicated in the establishment and maintenance of pregnancy. An increased abundance of signal transducers and activators of transcription (Stats) in the secretory phase suggests Stat5 as a component of the differentiation of endometrium in response to ovarian hormone stimulation in vivo. Decidualization is initiated in a subset of endometrial stromal cells (ESC) in vivo during the secretory phase, but it is unclear whether regulated expression of Stat5 is a feature of these cells. Here, therefore, the abundance and subcellular distribution of Stat5 in ESC after a decidualization stimulus of cAMP plus medroxyprogesterone acetate (MPA) has been investigated in vitro. Western blotting revealed an increase in the apparent abundance of Stat5a and Stat5b, in the cytosolic and nuclear fractions, at 2, 3, and 4 d after stimulation. The potential functional relevance of this increase in Stat5 is suggested by the ability of transiently transfected Stat5a or Stat5b to significantly enhance the response of the decidual PRL promoter to cAMP/MPA and attenuation of the response to cAMP/MPA by dominant negative Stat5. Recent evidence suggests endometrial differentiation, including PRL production, as a possible target of antiphospholipid antibodies (aPL) prevalent in recurrent miscarriage. Monoclonal antibody, ID2, which has similar reactivity as human aPL, significantly decreased the apparent abundance of nuclear Stat5b in response to cAMP/MPA and was associated with decreased decidual PRL promoter activation and PRL secretion. Regulated expression of Stat5 is therefore a component of decidual differentiation of human ESC and contributes significantly to activation of the decidual PRL promoter. Alteration of this process by an aPL component suggests decidual differentiation as a potential clinical target in recurrent early miscarriages.