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Jayasree Sengupta

Publications and source records attributed to Jayasree Sengupta.

13 recordsLinked to original sources
PubMed2006

Monoclonal anti-leukemia inhibitory factor antibody inhibits blastocyst implantation in the rhesus monkey.

INTRODUCTION: Leukemia inhibitory factor (LIF) appears important in the process of blastocyst implantation in primates. In the present study, we investigated the effect on pregnancy outcome of the administration of a monoclonal antibody (mAb) to recombinant human (rh) LIF (anti-LIF mAb) into the uterine cavity of mated female rhesus monkeys during the peri-implantation period. METHODS: Two milligrams of either mouse mAb to rhLIF or isotype-matched immunoglobulin (Ig) was administered into the uterine cavity on estimated Day 5 or Day 8 after ovulation either through the vagina (n=33) or through the oviduct (n=29) of successfully mated females. RESULTS: There was a significant (p<.04) decline in pregnancy outcome in groups treated with anti-LIF mAb (8 pregnancies from 32 animals) compared with control animals (24 pregnancies from 30 animals). There was, however, no significant difference in pregnancy inhibition between a group of animals subjected to vaginal route treatment and a group of animals subjected to oviductal route treatment, as well as between a group subjected to anti-LIF mAb on Day 5 after ovulation and a group subjected to anti-LIF mAb on Day 8 after ovulation. No significant change was seen in the number of viable pregnancy in animals treated with 6 mg of anti-LIF mAb (5 pregnancies from 16 animals) compared with animals treated with 2 mg of anti-LIF mAb (8 pregnancies from 32 animals). Serum profiles of estradiol, progesterone, monkey chorionic gonadotropin and mouse IgG did not show any difference among different treatment subgroups during the luteal phase. However, among animals treated with anti-LIF mAb, the mean area under the curve for serum mouse IgG in pregnant animals (234+/-55 microg/mL day) was significantly (p<.01) less than that of nonpregnant animals (1325+/-97 microg/mL day). CONCLUSION: The results of the present study put forward the proof of concept that LIF plays a critical role in the process of blastocyst implantation in the rhesus monkey.

Animals↗
PubMed2005

Target-oriented anti-implantation approaches for pregnancy interception: experiences in the rhesus monkey model.

Blastocyst implantation is a critical process in the establishment of pregnancy in eutherian mammals and requires a harmonious symbiosis between the developing conceptus and the differentiating maternal uterus. A better understanding of this symbiotic relationship will provide novel approaches and interventions for realizing anti-implantation strategies for effective fertility regulation and reproductive health care management. We have been using the rhesus monkey (Macaca mulatta) as a nonhuman primate model to this end. In the present study, the process of progesterone-mediated regulation of endometrial receptivity for blastocyst implantation has been targeted by the use of mifepristone as an emergency contraceptive agent. Furthermore, based on cell-specific, temporal and spatial distribution of vasotropic cytokines and mediators in the "receptive" and periimplantation periods, the pregnancy interceptive potentials of (a) monoclonal antibody (MAb) to leukemia inhibitory factor (LIF); (b) inhibitors of nitric oxide synthase [e.g., N6-nitro-l-arginine (l-NAME) and aminoguanidine]; and (c) MAb to vascular endothelial growth factor (VEGF) were examined. LIF is a progesterone-responsive pleiotropic cytokine that functions as a proinflammatory cytokine, together with interleukins 1 and 6, during the process of implantation-placentation in primates, and its immunoneutralization with MAb resulted in inhibition (p<.04) of pregnancy establishment in the rhesus monkey. However, timed administration of l-NAME or aminoguanidine failed to inhibit blastocyst implantation in a significant manner. Also, no synergistic antinidatory action of antiprogestin combined with l-NAME was detected in the rhesus monkey. The application of MAb to VEGF during the periimplantation period, on the other hand, led to significant (p<.04) prevention of pregnancy without influencing steroid hormone levels in the circulation. Our data lend support to the hypothesis that VEGF is essential for pregnancy establishment and that trophoblast-derived VEGF, acting via its specific receptors Flt-1 and KDR, is necessary for blastocyst implantation. The use of cDNA-based expression arrays followed by differential display analysis has provided preliminary understanding of the nature of gene cluster networks operative in the receptive endometrium of potential conception cycles in the rhesus monkey. This knowledge may, in the future, lead to further innovative anti-implantation strategies for targeted pregnancy interception.

Animals↗
PubMed2005

Nitric oxide in blastocyst implantation in the rhesus monkey.

Successful blastocyst implantation depends on the interaction between cells of maternal endometrium and conceptus, as well as adequate blood supply to the site of blastocyst implantation. Nitric oxide (NO) generally plays a significant role in the local regulation of vascular physiology in a variety of mammalian tissue systems, however, its role in blastocyst implantation and placentation in the primate is not known. The aim of the present study was to examine: (i) NADH-diaphorase activity and expression of three isoforms of nitric oxide synthase (NOS), namely endothelial NOS (eNOS), inducible NOS (iNOS) and neuronal NOS (nNOS) in pre-implantation stage monkey embryos, morula (n = 4) and blastocyst (n = 10), as well as, in different compartments of conceptus and maternal endometrium at primary implantation sites during lacunar (n = 6) and villous (n = 9) stages of placentation in the rhesus monkey, and (ii) the potential anti-nidatory effect of vaginal administration of NOS inhibitor during the peri-implantation period of conception cycles in rhesus monkeys. Pre-implantation stage blastocysts exhibited marked NADPH-diaphorase activity along with immunopositive iNOS mainly in the inner cell mass. During the lacunar stage, marked eNOS expression was observed in cytotrophoblast cells lining the embryonic cavity. However, cytotrophoblast cells lining villi, forming columns, and constituting anchoring villi expressed all the three isoforms of NOS in villous placenta stage tissue. During the lacunar stage, eNOS and iNOS protein expressions were observed in epithelial and decidual cells of endometrium. As gestation advanced, mRNAs for all three isoforms of NOS were observed to increase in epithelial and decidual cells, however, with no marked change in protein expression. Vaginal administration of a NOS inhibitor (N(G)-nitro-l-arginine methyl ester, L-NAME, 4, 6, and 8 mg/kg body weight or aminoguanidine, AG, 4 mg/kg body weight) during days 6 to 12 after ovulation resulted in pregnancy failure in a higher number of animals (L-NAME: 8 confirmed pregnancies in 25 animals; AG: 2 confirmed pregnancies in 8 animals) compared with control animals (5 pregnancies in 7 animals). It appears that NO may play an important role in the establishment of pregnancy in the rhesus monkey.

Animals↗
PubMed2005

Effect of (Ala8,13,18)-magainin II amide on human trophoblast cells in vitro.

Magainins are cationic peptides with anti-bacterial and anti-tumor properties. The anti-nidatory function of a synthetic analogue of magainin, (Ala8,13,18)-magainin II amide, has earlier been reported, and it has been indicated that placental trophoblast cells could be a target of magainin resulting in its contragestational action. The aim of the present study was to examine the effect of (Ala8,13,18)-magainin II amide (100 ng/ml and 1000 ng/ml) on attachment efficiency, viability, differentiation in terms of hCG secretion and invasive function of isolated first trimester, human placental trophoblast cells grown on rat-tail collagen type-I matrix in primary cell culture. In the present experimental model, magainin was not found to affect human trophoblast cell functions in vitro.

Amides↗
PubMed2005

Effect of tumour necrosis factor-alpha (TNF-alpha) on protein synthesis by mouse preimplantation stage embryos in vitro.

Successful blastocyst implantation depends upon the synchronous dialogue between age- and stage-matched embryo and adequately primed maternal endometrium. Endometrial signals present in the uterine lumen influence the growth and the viability of preimplantation stage embryo. Thus, uterine secretion of embryotoxic cytokines may affect the preimplantation stage embryo. Our previous study in the rhesus monkey has indicated that tumor necrosis factor-alpha (TNF-alpha) is one such candidate present in the uterine lumen, which may act as an embryotoxic agent. In the present study, the effect of TNF-alpha on de novo protein synthesis by mouse morulae (n = 100) and blastocysts (n = 100) in vitro was investigated by 2D-polyacrylamide gel electrophoresis. A total of 35 and 40 protein spots were detected in lysates of control morulae and blastocysts, respectively. Exposure of embryos to TNF-alpha (50 ng/ml) reduced the number of protein spots to 15 and 17 compared to that of control morulae and blastocysts. Seven spots in morula and 13 protein spots in blastocyst flourograms showed quantitative changes in their expressions with exposure to TNF-alpha. Morulae and blastocysts exposed to TNF-alpha expressed 8 and 17 protein spots, respectively, that were not seen in control embryos. It appears from the present study that exposure of preimplantation stage embryos to TNF-alpha affects their protein synthesis both quantitatively and qualitatively.

Animals↗
PubMed2004

Endocrine and paracrine correlates of endometrial receptivity to blastocyst implantation in the human.

Synchronous attainment of maternal endometrial receptivity allows implantation-stage adhesive blastocyst to undertake apposition, attachment and invasion. In the present essay, we propose a model according to which luteal phase progesterone induces a basic drive in endometrium toward receptivity and as a result, adequately primed endometrium differentiates through certain steps in a fixed action pattern. The implantation-stage embryo senses such endometrial responsiveness circumstantially by the factors secreted by maternal endometrium and undertakes differentiation to implant by secreting factors which act on maternal endometrial cells to further potentiate them to implantation stage-specific changes. Such a dynamic temporo-spatial manner of interaction involving a set of specific factors acting synchronously leads to the activation of innate releasing process in both compartments towards embryo attachment followed by successful intrusion and controlled invasion of trophoblast cells into maternal endometrium. In the present review we discuss the potential role of various endocrine and paracrine factors in the process of blastocyst implantation in the human.

Animals↗
PubMed2004

Immunohistochemical localization of macrophage CD68+, HLA-DR+, L1+ and CD44+ subsets in uterine endometrium during different phases of menstrual cycle.

Different tissue macrophage subsets were immunohistochemically examined in normal endometrial samples collected from proliferative (n=4), peri-ovulatory (n=6) and secretory (n=8) phases of menstrual cycles in women. The different macrophage subsets, namely CD68 (pan macrophage marker), CD44 (transmembrane adhesion molecule), HLA-DR (transmembrane heterodimeric protein involved in antigen presentation) and L1 (calprotectin)-positive cells, as well as, CD45 (common leucocytic antigen)-positive cells were examined on the basis of immunohistochemical staining, and areas of immunoprecipitation were analyzed morphometrically using computer-assisted video imaging system. The stage-specific distribution of receptors for estrogen (ER) and progesterone (PR) in endometrial cells were examined and morphometrically analyzed. There was an increase in the number of CD45+ cells (P < 0.01) and CD68+ cells (P < 0.05) in secretory phase endometrium compared with proliferative and peri-ovulatory phases. There was no remarkable cycle dependent pattern in HLA-DR+ and L1+ cells. However, there was an increase in CD44 immunopositive area in peri-ovulatory (P < 0.05) and in secretory (P < 0.01) phases of endometrium compared with proliferative phase endometrium. A higher (P < 0.01) degree of immunopositivity for ER was observed during peri-ovulatory phase, and for PR, during peri-ovulatory (P < 0.05) and secretory (P < 0.01) phases compared with proliferative phase of cycle. Positive correlations between areas occupied by (i) CD68+ cells and PR (P < 0.01), (ii) HLA-DR+ and L1+ cells (P < 0.05), (iii) CD45+ and CD68+ cells (P < 0.01), (iv) CD45+ and L1+ cells (P < 0.05), and (v) PR and L1+ cells (P < 0.05) were obtained. It appears that the recruitment of different macrophage subsets in human endometrium involves a complex set of endocrine and paracrine factors.

Antigens, CD↗
PubMed2003

Immunohistochemical localization of leukemia inhibitory factor, interleukins 1 and 6 at the primary implantation site in the rhesus monkey.

Blastocyst implantation and placentation involve localized inflammatory type of responses at and around the site of nidation. In the present study, the likely involvement of inflammatory cytokines, namely, leukemia inhibitory factor (LIF), interleukins 1 alpha and 1 beta (IL-1alpha and IL-1beta) and IL-6 at the primary implantation site of the rhesus monkey was examined immunocytochemically during lacunar (n=6) and villous (n=8) stages of gestation. Trophoblast cells and extraembryonic mesenchymal cells were immunopositive for LIF and IL-1alpha. The distribution of IL-1beta and IL-6 in trophoblast cells was low in lacunar stage samples, however, a higher degree of immunopositivity for IL-6 was observed in villous stage samples. Decidual cells were immunopositive for all the cytokines studied. In lacunar stage samples, plaque cells adjacent to implanted nidus were immunopositive for all the cytokines examined, and the degree of their immunoprecipitation increased, except that of IL-1beta, during the villous stage. Luminal and glandular epithelial cells were immunopositive for LIF, IL-1alpha, IL-1beta and IL-6 in lacunar and in villous stage samples. LIF immunopositivity was detected in endothelial cells of blood vessels within and below chorionic plate and cytotrophoblast shell, while vascular smooth muscle cells were positive for all the cytokines studied. The temporo-spatial characteristics of LIF, IL-1alpha, IL-1beta and IL-6 protein expressions in primary implantation sites of the rhesus monkey suggest that these pro-inflammatory cytokines play specific roles in regulating trophoblast cell proliferation, differentiation, invasion and associated maternal tissue remodelling during early gestation.

Animals↗
PubMed2003

A multiparametric study of the action of mifepristone used in emergency contraception using the Rhesus monkey as a primate model.

Mifepristone is a potent agent used in emergency contraception (EC). In the present study, we examined the contraceptive efficacy of mifepristone used in EC and then, using the model of mifepristone-based EC, we investigated its mechanism of action in the rhesus monkey. Sexually mature females were allowed to cohabitate with male animals from 1600 to 900 h of any one day of days 8-17 of cycle without (Group I; n = 6) and with a single dose of mifepristone (Group II, n = 31, 25 mg per animal, subcutaneous) 72 h postcoitus. Blood samples from all animals of Groups I and II were used to determine the concentrations of estradiol (E), progesterone (P) and chorionic gonadotrophin in peripheral circulation for retrospective analysis of the days of ovulation and blastocyst implantation. Four out of six animals (66.6%) in Group I became pregnant, while all 31 monkeys in Group II failed to establish pregnancy along with marginal changes in serum concentrations of E and P. In the second part of the study, animals were subjected to the same experimental protocol followed by collection of endometrial tissue samples on cycle day 22 from animals of both Group I (n = 6) and Group II (n = 24). Endometrial samples were subjected to morphological analysis including mitotic index, immunohistochemistry for vascular endothelial growth factor (VEGF), leukemia inhibitory factor (LIF), transforming growth factor beta1, estradiol receptor (ER), progesterone receptor (PR), proliferating cell nuclear antigen, placental protein 14 (PP 14) and detection of apoptosis by terminal nick end labeling method followed by histometric analysis. The results were retrospectively analyzed between the two groups on the basis of the day of treatment after ovulation: early luteal phase (days 0-3 postovulation) and mid-luteal phase (days 4-7 after ovulation). Mifepristone used in EC in the present study resulted in general loss of functional integrity of epithelial compartment characterized by loss of secretory maturation, increased apoptosis and higher degree of degeneration along with decreased expression of VEGF, LIF, PP14 and ER, while PR level increased as compared to control samples. The vascular compartment appeared to be compromised along with affected morphological features and decreased expression of VEGF, LIF, ER and PR following the administration of mifepristone. It appears that mifepristone used in EC alters the physiological homeostasis in epithelial and vascular compartments of implantation stage endometrium rendering it hostile to blastocyst implantation. Furthermore, the degree to which the endometrial function is affected largely depends on the day of mifepristone treatment in a parameter-specific manner resulting in a higher degree of degenerative changes in samples obtained from animals who received mifepristone during mid-luteal phase of cycles.

Animals↗
PubMed2003

Experimental models for human implantation.

An understanding of the cellular and molecular basis of blastocyst implantation in the human remains as yet a black box, however, a few experimental models using human and non-human primate species have addressed this issue. This review attempts to highlight, based on experimental evidence, the paradigm shifts in our understanding of the endocrine basis of embryo implantation, and the nature of dialogue between a growing, viable conceptus and maternal endometrial cells in the establishment of 'receptivity' for blastocyst implantation. It is being proposed that an existing inflammation paradigm of blastocyst implantation could be tested using an experimental model to compare tissue behaviour of conceptus associated endometrial cells with that occurring after induction of deciduoma in hormone-primed uterus. We anticipate that an in vitro model of blastocyst implantation using the experimental models of homotypic and heterotypic cultures of uterine epithelial and stromal fibroblast cells expressing structural and functional phenotypic responses as observed in situ may provide us with necessary clues about the temporal and spatial nature of cellular and molecular functions involving various endocrine and paracrine factors at implantation.

Animals↗
PubMed2002

Effect of vaginally administered fumagillin on immunohistochemical distribution of leukemia inhibitory factor, interleukin 6, transforming growth factor beta and vascular endothelial growth factor in implantation stage endometrium of the rhesus monkey.

Intravaginal administration of an anti-angiogenic agent, fumagillin, during blastocyst implantation inhibits pregnancy establishment in a dose-related manner in the rhesus monkey. In the present study, mated female rhesus monkeys were vaginally inserted with tampons containing vehicle (group 1; n = 5) and test agent (fumagillin, 4 mg/animal; group 2; n = 6) on cycle day 20, and endometrial tissue samples were collected on cycle day 24 from all monkeys and processed for histological examination and immunohistochemical localization for LIF, IL-6, TGF-beta and VEGF. Concentrations of estradiol-17 beta, progesterone and chorionic gonadotrophin in peripheral circulation were determined. From the serum profiles of the hormones, 2 monkeys in group 1, and 1 monkey in group 2 appeared pregnant. However, endometrial morphology revealed histological evidence of pregnancy in 3 out of 6 fumagillin-treated animals. Histometric analysis of immunohistochemical staining in epithelial, stromal and vascular compartments revealed that per cent areas occupied by immunoprecipitate for the cytokines studies did not change in epithelial and stromal compartments, except that for TGF-beta which was higher (P < 0.05) in epithelial compartment in group 2. No change was observed in immunoprecipitation areas for IL-6 in epithelial, stromal and vascular compartments. On the other hand, changes (P < 0.05) for LIF, TGF-beta and VEGF were evident in the vascular compartment. It is possible that disparate responses observed in glandular, stromal and vascular compartments in implantation stage endometrium following fumagillin treatment actually caused from associated decline in progesterone concentration in peripheral circulation. It is also possible that fumagillin, an angiostatic agent, affects the synthesis and secretion of cytokines primarily in the vascular compartment of implantation stage endometrium, and thereby manifests differential responses in epithelial, stromal and vascular compartments.

Administration, Intravaginal↗
PubMedDate not supplied

Immunohistological localization of insulin-like growth factor binding protein-1 in primary implantation sites and trauma-induced deciduomal tissues of the rhesus monkey.

We have earlier demonstrated that there is a close similarity in the temporo-spatial pattern in the onset of oedema, epithelial-plaque transformation, stromal decidualization and influx of granulated lymphocytes in artificially trauma-induced deciduomal endometrium with such events in maternal endometrium at the primary implantation site during early stages of pregnancy in the rhesus monkey. In the present study, we have immunohistochemically examined whether the pattern of insulin-like growth factor-binding protein 1 (IGFBP-1) protein expression in conceptus tissue and maternal endometrium during lacunae and villous placenta stages of gestation in the rhesus monkey is developmental stage-specific and whether a discernible difference exists in the temporo-spatial characteristics of IGFBP-1 protein expression between conceptus associated implantation-decidualization and trauma induced deciduoma in the rhesus monkey. Trophoblast cells failed to exhibit IGFBP-1 immunopositive staining at any stage of implantation-placentation studied. Epithelial cells in plaque acini, endothelial cells, and vascular smooth muscle also did not show any immunopositive staining for IGFBP-1 in samples of primary implantation sites and trauma-induced deciduoma. Maternal endometrial epithelial and stromal-decidual cells however exhibited a temporal and spatial pattern of IGFBP-1 expression in cell-type specific manner and clear distinctions were observed between conception and deciduoma samples. Our results suggest that IGFBP-1 expression is highly tissue and development-specific and that conceptus-derived signals are necessary to initiate the glandular expression of IGFBP-1 during the early stage of gestation.

Animals↗