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H Bohn

Publications and source records attributed to H Bohn.

At least 55 records · Page 3Linked to original sources
PubMed1989

Immunochemical measurement and immunohistochemical detection of membrane-associated placental tissue protein 1.

Using the avidin-biotin binding system, an enzyme immunoassay procedure was developed to measure the membrane-associated placental tissue protein 1 (MP1) in serum. The standard curve covered the range from 10 to 1000 ng/ml of MP1. The intra- and inter-assay coefficient of variations (C.Vs) were less than 5 and 10%, respectively. Recoveries of MP1 added to serum ranged between about 96 and 101%. The MP1 serum level was over 10 and under 112 ng/ml in non-pathological men, and under 240 ng/ml in non-pathological women. The MP1 level in the ovulatory phase was higher than in other phases of the menstrual cycle. In pregnancies during 6-39 weeks, the MP1 level ranged from 10 to 540 ng/ml, and it increased during the third trimester of gestational age. In benign gynecologic diseases, the MP1 concentration in serum ranged from 10 to 215 ng/ml. The MP1 levels in benign diseases were compared with those in ovarian malignancies, in endometrial carcinoma, and in uterine cervical cancer. The immunohistochemical location of MP1 was detected in the cell membrane of ovarian cystadenocarcinoma.

Female↗
PubMed1989

Synthesis of polypeptides by the cervix of the baboon (Papio anubis).

Administration of oestradiol to ovariectomized baboons caused the epithelium of the cervix to differentiate into tall columnar cells that were ciliated or secretory. Administration of progesterone in the presence or absence of oestradiol altered the appearance of the lining epithelium, suggesting a decrease in secretory activity. Fluorographs of media from cultures of tissue from steroid-treated animals reflected changes in polypeptide biosynthesis which correlated with the morphological observations: 6 polypeptides (Mr 88,000-37,000; pI 5.5-6.0) were observed in all treatment groups and, except for relative changes in intensity, these polypeptides were electrophoretically similar to those synthesized by the endometrium. A new group of low molecular weight polypeptides (Mr 23,000-20,000, pI greater than 8.0-5.5) and a basic protein (Mr 160,000) were synthesized and released in the oestradiol-dominated animal. These polypeptides were distinct to the cervical mucosa since they were not observed in the endometrium or oviduct. Progesterone suppressed the synthesis of the low molecular weight acidic polypeptides (Mr 23,000-20,000; pI 6.1-5.5) but maintained the synthesis of the basic polypeptides (Mr 23,000-20,000; pI greater than 8). Treatment with progesterone +/- oestradiol did not appear to induce the synthesis of any new major polypeptides in the cervical epithelium. These results suggest that oestradiol induces the synthesis of a group of cervix-specific polypeptides and progesterone antagonizes the action of oestradiol in the baboon cervix.

Animals↗
PubMed1989

Oxygen and oxidation promote the release of nitric oxide from sydnonimines.

The antianginal effect of sydnonimines is believed to be due to the release of nitric oxide (NO) from inactive prodrugs. The first step in the transformation of the sydnonimine SIN-1 is the hydroxyl ion-dependent conversion to SIN-1A that occurs almost immediately at neutral pH. However, the subsequent process of NO release from SIN-1A is not yet understood. Therefore, the spontaneous degradation of SIN-1A in aqueous solutions was studied by chemical and pharmacological means. Measurement of the oxygen content of a freshly prepared SIN-1A solution revealed a rapid decrease of the oxygen concentration. The oxygen-consuming process was accompanied by a decrease in SIN-1A concentration and a progressive formation of NO and SIN-1C. SIN-1A was stable under nitrogen, labile under air, and very unstable under pure oxygen. Thus, oxygen is an important reactant in the decomposition of SIN-1A. The question of whether or not oxygen is essential for NO release was studied by investigating the effect of other oxidants. The oxidants potassium hexacyanoferrate, cupric sulfate, and lead tetraacetate augmented the conversion of SIN-1A to SIN-1C and increased the relaxing effect on isolated pulmonary arteries used to bioassay NO. Therefore, an oxidative process is essential for the release of NO from sydnonimines.

Biological Assay↗
PubMed1988

High molecular weight forms of insulin-like growth factor II and its binding protein identified by protein immunoblotting.

Insulin-like growth factor (IGF)II is a mitogenic polypeptide which circulates in association with a binding protein(s). Immunoblotting studies were performed in human serum and indicate that:(1)a approximately 200 kDa covalently-linked IGF-II/binding protein complex is antigenically related to the 30 kDa binding protein, (2)IGF-II prohormone is associated with this complex, and (3)a major portion of the IGF-II prohormone immunoreactivity in human serum is present in fractions which would not be detected by standard radioimmunoassay methods. Our data provide insight regarding the inter-relationships of IGF-II and its binding protein, and direct evidence for the presence of IGF-II prohormone in human serum.

Humans↗
PubMed1988

Purification and characterization of placental protein 5.

This report describes the purification of placental protein 5, PP5, from the human placenta by two affinity chromatography steps, the first with Heparin-Sepharose and the second with Sepharose-linked monoclonal anti-PP5 antibody. The final purification is achieved by reversed-phase high performance liquid chromatography. In SDS-polyacrylamide gel electrophoresis under reducing or nonreducing conditions, PP5 purified in this study migrates as one major band at 36 kD. The previously purified PP5 is more heterogeneous: under nonreducing conditions it migrates at 30 kD and, after reduction, it gives three bands at 16.8 kD, 18.3 kD, and 19.0 kD. In Western blot analysis, both purified proteins react with polyclonal and monoclonal anti-PP5 antibodies. Three N-terminal amino acid sequences are obtained for the previously purified PP5, whereas the N-terminal of PP5 purified in this study is blocked. These results suggest that PP5 previously purified in the absence of protease inhibitors, does not represent the native form of PP5. Computer comparison of the obtained amino acid sequences revealed no significant homology to known protein sequences.

Amino Acid Sequence↗
PubMed1988

Beta lactoglobulin homologue placental protein 14 (PP14) in serum of patients with trophoblastic disease and non-trophoblastic gynecologic malignancy.

Serum levels of beta lactoglobulin homologue placental protein 14 (PP14) were measured by a sensitive radioimmunoassay in various trophoblastic diseases and non-trophoblastic gynecologic malignancies. While trace amounts of protein were detected in sera of non-pregnant subjects (22.3 +/- 13.7 micrograms/l), during first half of normal pregnancy a dramatic rise of serum-PP14 levels was demonstrable with a peak-value at 7th-10th week of gestation, followed by a decline thereafter. Serial determinations of PP14 have been performed in 31 patients with trophoblastic tumour (20 hydatidiform moles, 4 invasive moles and 7 choriocarcinomas). In patients with hydatidiform moles and invasive moles (273.5 +/- 106.5 micrograms/l and 162.2 +/- 109.6 micrograms/l) respective values before therapy were much exceeding the non-pregnant controls. After therapy there was a rapid decline of the serum-PP14 levels within two weeks. In patients with choriocarcinoma the PP14 values were moderately elevated (66.4 +/- 25.7 micrograms/l), and declined following the remission of disease. In 32 gynecological tumours (21 carcinomas of the cervix, 4 endometrial carcinomas, 5 ovarian carcinomas, 2 carcinomas of the vulva) the pretreatment levels were not different to normal controls.

Choriocarcinoma↗
PubMed1988

Serum PP12, PP14, SP1 and hCG values in the 28 days after the LH-surge in patients who do and do not conceive after artificial insemination or in vitro fertilization.

Serum levels of PP12 (somatomedin binding protein), PP14 (beta lactoglobulin homologue), Schwangerschaftsprotein 1 (SP1) and of human chorionic gonadotropin (hCG) were simultaneously measured in patients being treated for infertility in the 28 days after the LH-surge. PP14 levels were similar in the 14 days after the LH-surge in the patients who conceived when compared with those who did not and a high PP14 level was only indicative of pregnancy at 21 days after the LH-surge. hCG and SP1 levels behaved similarly in pregnant subjects. PP12 levels did not change significantly in the 28-days after the LH-surge.

Chorionic Gonadotropin↗
PubMed1988

Two fetal antigens (FA-1 and FA-2) and endometrial proteins (PP12 and PP14) isolated from amniotic fluid; preliminary observations in fetal and maternal tissues.

Rabbit antihuman antibodies were derived by the injection of fractions of second trimester amniotic fluid known to contain proteins of endometrial/decidual origin. Using standard separation and absorption procedures, two antibody preparations were generated which demonstrated specificities against two and three proteins, respectively, in line immunoelectrophoresis and crossed immunoelectrophoresis. Analysis against proteins of fetal, maternal, endometrial and placental origin revealed that the bispecific antiserum reacted only with placental protein 14 (PP14; also known as progestagen-dependent endometrial protein, PEP) and one other hitherto undescribed antigen referred to as Fetal Antigen 1 (FA-1) molecular mass 60 kDa; electrophoretic mobility: slow; alpha 1-alpha 2; fast, albumin. The trispecific antiserum demonstrated specifities against placental protein 12 (PP12), alpha-fetoprotein (AFP) and another previously undescribed antigen referred to as Fetal Antigen 2 (FA-2) molecular mass 35 and 140 kDa; electrophoretic mobility: albumin. Following purification, monospecific antisera against each of these proteins (with the exception of AFP) were derived in new rabbits. Maternal and fetal blood, amniotic fluid and aqueous extracts from endometrial/decidual and placental tissues were analysed in rocket immunoelectrophoresis using these antisera to examine the distribution in these tissues. The analyses demonstrated a pattern of distribution typical for proteins of endometrial/decidual origin in these compartments in the case of PP12 and PP14, but suggested that the primary source of origin of FA-1 and FA-2 may be the fetus.

Amniotic Fluid↗
PubMed1988

Characterization of cDNA encoding human placental anticoagulant protein (PP4): homology with the lipocortin family.

A cDNA library prepared from human placenta was screened for sequences encoding the placental protein 4 (PP4). PP4 is an anticoagulant protein that acts as an indirect inhibitor of the thromboplastin-specific complex, which is involved in the blood coagulation cascade. Partial amino acid sequence information from PP4-derived cyanogen bromide fragments was used to design three oligonucleotide probes for screening the library. From 10(6)independent recombinants, 18 clones were identified that hybridized to all three probes. These 18 recombinants contained cDNA inserts encoding a protein of 320 amino acid residues. In addition to the PP4 cDNA we identified 9 other recombinants encoding a protein with considerable similarity (74%) TO PP4, which was termed PP4-X. PP4 and PP4-X belong to the lipocortin family, as judged by their homology to lipocortin I and calpactin I.

Amino Acid Sequence↗
PubMed1988

Characteristic differences in immunohistochemical localization of new placental proteins (PP1, PP19, PP21) in the human placenta.

The immunohistochemical localization in the human placenta of new placental proteins PP1, PP19, and PP21 was clarified using modified indirect enzyme-labeled antibody method and compared with that of pregnancy-specific beta 1-glycoprotein (SP1). The major results are as follows: positive staining for PP1 was seen at the nucleus and cytoplasm of villous cytotrophoblasts, the X cells at the basal plate, and of chorionic trophoblasts, while the decidua cells and amnion were not stained. PP19 was characteristically seen in the nucleus and cytoplasm of syncytiotrophoblasts. X cells in basal plate, chorionic trophoblasts, and maternal leukocytes. The villous cytotrophoblasts, decidua cells, and amnion were not stained. PP21 localization was found at the microvilli and basal membrane of syncytiotrophoblasts and at the cytotrophoblast plasma membrane of the chorionic villus in early gestation. In late gestation, increased staining was seen at the syncytiotrophoblast microvilli and the villous basement membrane, and moderate staining at plasma membrane of the amniotic epithelium and chorionic trophoblasts. SP1 was found only at the syncytiotrophoblast cytoplasm of chorionic villi. Studies using these four placental proteins simultaneously may therefore provide a new key learning about unknown metabolic functions of trophoblasts.

Basement Membrane↗
PubMed1988

Placental protein 21. Localization in human placenta and concentrations in the body fluids of men and nonpregnant and pregnant women.

The immunohistochemical localization of placental protein 21 (PP21) was marked in the syncytial brush border and basal membrane during the 1st and 2nd trimesters of pregnancy and also in the chorionic epithelial brush border and basement membrane at term. A weaker stain was found in the cell membranes of amniotic epithelial and chorionic trophoblast cells. Neither heparin nor changes in temperature significantly influenced PP21 concentration. Relatively high serum PP21 concentrations were measured during the follicular and luteal phases in healthy nonpregnant women and in healthy men whose seminal plasma also showed a high PP21 concentration. Serum PP21 levels in normal pregnancy rose from a median of 29.1 ng/ml at 6-7 weeks of gestation to 82.0 ng/ml at 36-37 weeks of gestation. Although maternal urine showed low PP21 levels during pregnancy, amniotic fluid PP21 levels were higher at 7-21 weeks of gestation than at term. Cord blood sera showed almost the same PP21 concentration as maternal sera, but retroplacental blood showed much higher levels. Maternal serum PP21 levels in hydatidiform mole patients did not differ from the normal pregnancy range, although their molar vesicular fluids contained higher PP21 concentrations. These results suggest an extraplacental source for PP21.

Adult↗
PubMed1988

Insulin-like growth factor (IGF) binding protein from human decidua inhibits the binding and biological action of IGF-I in cultured choriocarcinoma cells.

The placenta expresses genes for insulin-like growth factors (IGFs) and possesses IGF-receptors, suggesting that placental growth is regulated by IGFs in an autocrine manner. We have previously shown that human decidua, but not placenta, synthesizes and secretes a 34 K IGF-binding protein (34 K IGF-BP) called placental protein 12. We now used human choriocarcinoma JEG-3 cell monolayer cultures and recombinant (Thr59)IGF-I as a model to study whether the decidual 34 K IGF-BP is able to modulate the receptor binding and biological activity of IGFs in trophoblasts. JEG-3 cells, which possess type I IGF receptors, were unable to produce IGF-BPs. Purified 34 K IGF-BP specifically bound [125I]iodo-(Thr59)IGF-I. Multiplication-stimulating activity had 2.5% the potency of (Thr59)IGF-I, and insulin had no effect on the binding of [125I] iodo-(Thr59)IGF-I. 34 K IGF-BP inhibited the binding of [125I] iodo-(Thr59)IGF-I to JEG-3 monolayers in a concentration-dependent manner by forming with the tracer a soluble complex that could not bind to the cell surface as demonstrated by competitive binding and cross-linking experiments. After incubating the cell monolayers with [125I]iodo-(Thr59)IGF-I in the presence of purified binding protein, followed by cross-linking, no affinity labeled bands were seen on autoradiography. In contrast, an intensely labeled band at 40 K was detected when the incubation medium was analyzed, suggesting that (Thr59)IGF-I and 34 K IGF-BP formed a complex in a 1:1 molar ratio. Also, 34 K IGF-BP inhibited both basal and IGF-I-stimulated uptake of alpha-[3H]aminoisobutyric acid in JEG-3 cells. RNA analysis revealed that IGF-II is expressed in JEG-3 cells. We conclude that decidual 34 K IGF-BP inhibits the cellular binding and biological action of IGFs in JEG-3 cells. Our data show that JEG-3 cells represent a cell type that can produce IGF, but not IGF-BPs. These cells may thus provide a useful model system for a better understanding of autocrine growth regulation mediated by the IGFs.

Binding, Competitive↗
PubMed1988

Monoclonal antibodies reacting with placental protein 5: use in radioimmunoassay, Western blot analysis, and immunohistochemistry.

Monoclonal antibodies were raised reacting with placental protein 5 (PP5), a glycoprotein with properties of a serine protease inhibitor. Immunization was carried out with an antigen purified from late pregnancy placenta tissues. After fusion with myeloma cells, clones producing antibodies reacting with PP5 were isolated. Antibodies produced by two of the established hybridoma clones were characterized. The Ka of the antibodies was 0.22 x 10(9) L/mol and 0.3 x 10(8) L/mol. in Western blot analysis, both monoclonal antibodies reacted with the purified antigen that had a relative molecular weight (Mr) of 30 kd, but minor components of Mr 27 kd, 56 kd, and 62 kd were also identified. In polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate under reducing conditions, the purified protein yielded three polypeptides (Mrs of 16.4 kd, 16.8 kd, and 18.3 kd) that did not react with the monoclonal antibodies in Western blot analysis. By immunoperoxidase staining with monoclonal and polyclonal antibodies, PP5 was localized to the syncytiotrophoblast, cytotrophoblast, and endothelium of early and late pregnancy placenta tissues, whereas various other tissues were PP5-negative. In immunofluorescence staining, isolated endothelial cells were stained with both monoclonal antibodies. Endothelial cells in monolayer culture released into the medium a substance that is immunologically similar to purified PP5.

Animals↗
PubMed1988

Immunofluorometric demonstration and quantification of placental protein 5 in the absence of pregnancy.

This time-resolved immunofluorometric assay (IFMA) developed for measurement of placental protein 5 (PP5) involves two antibodies: a monoclonal anti-PP5 antibody attached to a solid phase and an europium(III) chelate-labeled polyclonal anti-PP5 antibody as a tracer. The measuring range is 0.05-100 micrograms/L and the detection limit is 20 times lower than that of a PP5 radioimmunoassay (RIA) performed with the same polyclonal antiserum. By IFMA, PP5 could be detected and quantified in all plasma and serum samples of nonpregnant and pregnant individuals, whereas PP5 was undetectable by RIA in serum of healthy men and nonpregnant women. The mean concentration of PP5 in sera from men was 0.43 micrograms/L (SD 0.13, range 0.19-0.75, n = 47) and in sera from nonpregnant women 0.49 micrograms/L (SD 0.19, range 0.20-0.90, n = 41). PP5 concentrations in serum showed no systematic variation during the menstrual cycle. In serum samples from 60 pregnant women the results obtained by IFMA and RIA correlated well (r = 0.97).

Female↗
PubMed1987

In vitro and in vivo studies of the production of placental proteins (HCG, SP1, PPs) in human choriocarcinoma cell lines.

The production of human chorionic gonadotropin (hCG), pregnancy-specific beta-1 glycoprotein (SP1), and the various placental tissue proteins (PP4, PP5, PP10, PP11, PP12, MP1) was examined in human choriocarcinoma cell lines using radioimmunoassay (RIA) and an immunoperoxidase (PAP) staining method. In 6 gestational and 2 nongestational choriocarcinoma cell lines, hCG was produced in vitro. A significant heterogeneity of hCG production was noted among the cell lines. Production of hCG in the xenograft tumors was consistent with the hCG production of the same cell lines in vitro. SP1 was demonstrated both in the culture supernatants and the xenograft tumors of 3 cell lines, and the production was found to be inversely correlated with the hCG production of the cell lines. Positive staining for PP4 and MP1, and weakly positive staining for PP5, PP10, and PP12 was found in the xenograft tumors by immunoperoxidase (PAP) stain, but the staining for PP11 was negative. These placental proteins showed positive staining in portions of choriocarcinoma cells. These results indicate that placental proteins are not equally produced in heterogeneous choriocarcinoma cells.

Animals↗
PubMed1987

Placental protein 10: levels in benign and malignant ovarian cyst fluids and pleural exudates.

Placental protein 10 (PP10) was measured in benign (n = 47) and malignant (n = 10) ovarian cyst fluids and in pleural fluid specimens from 19 patients with pleural metastases of various carcinomas (n = 15) or infectious pleurisy (n = 4). PP10 was found in 9 out of 18 follicular or luteal cyst fluids (range 2.0-42.0 micrograms/l) and in 24 out of 29 benign ovarian tumours (range 2.6-38.0 micrograms/l). Nine out of ten malignant ovarian cyst fluids contained detectable PP10 (range 4.0-55.2 micrograms/l). PP10 was found in all the pleural fluids from 15 patients with metastatic bronchial, pulmonary, breast or pancreatic carcinomas (range 5.1-100.2 micrograms/l), as well as from four patients with pleurisy (range 5.0-28.6 micrograms/l). Our results indicate that PP10 is tumour-associated, but not tumour-specific.

Female↗