Properties of human pre- and post-implantation embryo-associated immunosuppressor factor(s)

Embryo associated immunosuppressor factor (EASF) and serum estradiol synergism in pre-embryonic development after in vitro fertilization

The aim of this study was to test whether the level of serum immunosuppressor factor (EASF) and serum estradiol (E2) play a cooperative role in the pre-implantation early embryonic development in IVF-patients. Serum samples were collected from 80 patients undergoing IVF-ET and the level of EASF in patient's sera was assayed using a two-site sandwich enzyme linked immunosorbent assay (ELISA) system. Two-hundred fifty-one IVF-culture media were obtained from these patients and the EASF activity was measured using concanavalin A-induced lymphocyte proliferation assay. EASF activity in embryo growth media, quality of ova, number of cells in each pre-embryo at the time of embryo transfer, cycle day 3 serum E2 and peak E2 levels were correlated with pregnancy outcome. Thirty-three out of 80 patients had detectable levels of serum EASF. The number of pre-embryos with > 4 cell stage at the time of embryo transfer correlated with the total number of ova retrieved in patients positive for serum EASF (P = 0.01) and patients that had an ongoing pregnancy at 7-8 weeks (P < 0.01). Ratio of the number of pre-embryos with > 4 cell stage at the time of embryo transfer and total number of ova retrieved correlated with cycle day 3 serum E2 (P < 0.01) and peak E2 (P = 0.01) levels only in patients positive for EASF. The EASF activity of embryo growth media correlated with cycle day 3 serum E2 (P = 0.0001) and peak E2 (P = 0.007) levels only in patients that were positive for EASF and got pregnant after IVF-ET. This study suggests that the levels of serum EASF and E2 may act synergistically in the development of early embryo.

High levels of spermine in IVF medium as a negative predictor of subsequent success of embryo transfer

PURPOSE

Our purpose was to test the prediction that spermine levels in IVF culture supernatants measure by rapid ELISA assay correlate with subsequent success or failure to establish a pregnancy.

RESULTS

Forty-nine patients undergoing gonadotropin-stimulated ovulation after LHRH analogue treatment in the current study succeeded and 57 failed. With the exception of the first 4 hr of culture, where polyamine levels were slightly (but not significantly) higher in supernatants associated with subsequent success, higher levels of polyamines were predictive of failure.

CONCLUSIONS

The result in this study differs from previous data obtained with women ovulated using clomiphene where low spermine levels (assayed in an immunosuppression assay in vitro) correlated with failure to establish pregnancy, and detectable levels correlated with success. Supplementation of IVF culture medium with spermine and/or spermidine appears unlikely to improve IVF success rates, where the success rate is already very good, and may possibly do harm. The possibility that different methods of ovulation affect subsequent polyamine production in vitro by fertilized oocytes merits further study.

Hormonal and pregnancy relationships to rheumatoid arthritis: convergent effects with immunologic and microvascular systems

OBJECTIVE

To review sex hormones and rheumatoid arthritis (RA) and the interrelationships between hormonal, immunological, and vascular systems.

DATA SOURCES

Publications detailing serum sex hormone levels and their HLA interactions, steroidogenesis, pregnancy, and therapeutic uses of sex hormones in RA.

STUDY SELECTION

Controlled studies of sex hormone levels in RA patients not previously treated with glucocorticoids.

DATA EXTRACTION

Mean (+/- SD) serum levels of dehydroepiandrosterone sulfate (DHEAS), testosterone (T), and estradiol (E2).

DATA SYNTHESIS

Mean (+/- SD) levels were collated into tables for women with pre-versus postmenopausal onsets of disease and men. Data were also ordered across all study groups by increasing mean levels of the control subjects. Pooled data were summarized statistically, and major sources of variation between the studies were identified.

CONCLUSIONS

Serum DHEAS, an adrenal androgen, was impressively decreased among women with premenopausal onset of RA. One study showed such deficiency years before disease onset. Serum T was somewhat decreased in the premenopausal onset group, but could be explained by decreased peripheral conversion of the lower levels of adrenal androgens. Women with postmenopausal onset of RA had modestly decreased serum DHEAS levels overall, but no difference in serum T, compared with controls. Male RA cases had consistently decreased serum levels of T, but not of DHEAS. Serum E2 was comparable in all RA versus control groups. The complex biology of pregnancy was interpreted as an example of vital interactions between hormonal, immunological, and vascular systems, as they may relate to the physiopathology of RA. The major age, sex, and hereditable determinants of RA were compared within a composite table of estimated relative risks. Elucidation of the interacting risk factors offers promising avenues of research in this complex disease.

Embryo-associated immunosuppressor factor is produced at the maternal-fetal interface in human pregnancy

PROBLEM

To study whether embryo associated immunosuppressor factor (EASF) is synthesized at the maternal-fetal interface.

METHOD

Anti-EASF monoclonal antibody H5D12 was used to identify EASF. Paraffin-embedded sections were prepared from placental and fetal tissues and immunohistochemistry was done by the avidin-biotin-peroxidase technique. EASF was affinity purified using H5D12-Sepharose 4B from culture media of placental villi and analyzed for immunosuppressive activity (by Concanavalin A-induced lymphocyte proliferation assay) and molecular weight identity (by metabolic labeling studies with 35S-methionine followed by immunoprecipitation and SDS-PAGE).

RESULTS

Immunohistochemical studies demonstrates intense immunostaining of villous syncytiotrophoblast and cytotrophoblast cells of first trimester placental tissues. Hoffbauer cells and decidual cells stained positive. The same cells in second and third trimester placental tissues stained weakly. However, the endothelium and smooth muscle cells of fetal blood vessels, fetal ovarian stroma and primordial follicles, kidney epithelium, cerebral neurons, and glial cells all stained negative. The affinity-purified EASF from the conditioned media of placental villi (less than 12 wk gestational age) was identified as a 37-kDa molecule with immunosuppressive activity. Metabolic labeling studies revealed that placental villi from early gestational age secretes a major factor of 37-kDa and minor factors of 41-kDa and 47-kDa molecular weight.

CONCLUSIONS

Monoclonal antibody H5D12 identifies a factor that is produced by the pre-implantation embryo and also synthesized by decidua and trophoblast cells.

H5D12 monoclonal antibody identifies a 24-kD immunosuppressor factor produced by human chorio carcinoma cells

PROBLEM

The purpose of this study was to identify and characterize embryo-associated immunosuppressor factor (EASF) secreted by chorio carcinoma cells with the help of EASF-specific monoclonal antibody H5D12 (raised against EASF purified from embryo growth media of in vitro fertilized human ova).

METHOD

Paraffin-embedded slides of human chorio carcinoma as well as control cell lines were prepared, and immunohistochemistry was done by the avidin-biotin-peroxidase technique. EASF was affinity purified using H5D12-Sepharose 4B from culture media of cell lines and analyzed for immunosuppressive activity (by Concanavalin-A-induced lymphocyte proliferation assay) and molecular weight identity (by metabolic-labelling studies with 35S-methionine followed by immunoprecipitation and SDS-PAGE).

RESULTS

H5D12 showed intense immunostaining of BeWo chorio carcinoma cells. Biosynthetic labeling studies identifies this factor as a 24-kD molecule, and EASF bioassay indicates that this factor possesses immunosuppressive activity. No such immunosuppressive activity or similar molecules were identified when control cell lines were analyzed.

CONCLUSIONS

Monoclonal antibody H5D12 recognizes a 24-kD factor with immunosuppressive activity that is secreted by chorio carcinoma cells, which suggests that this is a unique factor and may be one of the key regulators of reproductive functions.

Human embryo associated immunosuppressor factor and serum estradiol synergism in ovarian follicle development

PROBLEM

The purpose of this study was to test whether the level of serum immunosuppressor factor (EASF) correlates with ovarian follicle development and with serum hormones during the ovarian cycle.

METHOD

One hundred seventy-three serum samples were collected starting at the time of ovulation and 1 wk after insemination from 29 women attempting pregnancy by ovarian hyperstimulation and intrauterine insemination. After ovarian stimulation, the patients were given human chorionic gonadotropin (hCG) 38 h before insemination. Number and size of follicles were measured by ultrasound. Serum samples were tested for hCG, estradiol (E2), luteinizing hormone, follicle-stimulating hormone (FSH), and progesterone levels. The level of EASF in patients' sera was assayed using a two-site sandwich enzyme-linked immunosorbent assay system. The levels of different hormones and EASF were then correlated among themselves and with the number of ovarian follicles.

RESULTS

Eleven out of 29 patients had detectable levels of serum EASF-Patients positive for EASF had a significantly higher number ovarian follicles > or = 13 mm and E2 levels after hCG treatment as compared to patients with no detectable EASF. The levels of EASF correlated with number of follicles (P = .001), blood E2 (P < .02) and FSH levels (P < .02). Number of follicles > or = 13 mm correlated with E2 (P = .01) and FSH levels (P < .01) only in patients positive for EASF.

CONCLUSIONS

The levels of EASF, E2; and FSH may act synergistically in the development of ovarian follicles.

Production and characterization of monoclonal antibodies to embryo-associated immunosuppressor factor (EASF) produced by human pre-implantation embryo

Balb/c mice were immunized with pre-implantation embryo-associated immunosuppressor factor (EASF) (purified from embryo growth media of in vitro fertilized human ova). Hybridoma clones were produced by fusing their spleen cells with NS1 and P3X653 myeloma cell lines. The presence of specific anti-EASF monoclonal antibodies (mAb) in the hybridoma culture supernatants were tested by enzyme-linked immunosorbent assay. A total of 15 hybridoma clones were selected, and their products were purified and characterized. Each mAb bound specifically to its antigen in a dose-dependent manner. The affinity-purified EASF from embryo growth media demonstrated immunosuppressive activity on Concanavalin A-induced lymphocytes and the presence of 14 kDa, 24 kDa and 37 kDa factors. No such activity or similar molecules were identified when control growth media were analyzed. This clearly demonstrates that these mAb are indeed EASF-specific and are able to recognize biologically active immunosuppressive components in embryo growth media. These mAbs are presently being tested for the development of EASF-specific assay system.