Eine quantitative Bestimmung von Faktor XIII mit Anti-Faktor-XIII-Serum

Eine neue Methode zur quantitativen Bestimmung von Faktor XIII wird beschrieben. Sie beruht auf der Verwendung von Anti-Faktor-XIII-Serum als Inhibitor in einem Hemmtest. Die Wirkung des Inhibitors ist spezifisch; aus der zur vollständigen Hemmung der Enzymaktivität notwendigen Menge an Antiserum läßt sich auf einfache Weise der Gehalt an Faktor XIII relativ zu einem als Standard gewählten normalen Mischplasma ermitteln.

Als Beispiel für die Anwendung wird das Ergebnis einer Untersuchung von 25 normalen Plasmen gesunder Einzelspender mitgeteilt. Die Werte der Faktor-XIII-Aktivität lagen zwischen 50% und 150% des Durchschnittswertes.

Isolierung und Charakterisierung des fibrinstabilisierenden Faktors aus menschlichen Thrombozyten

Der fibrinstabilisierende Faktor der menschlichen Thrombozyten wurde isoliert und rein in kristalliner Form erhalten. Seine Eigenschaften werden mit denen von Plasma-Faktor XIII verglichen. Physikalisch-chemisch unterscheidet sich der Thrombozyten-Faktor XIII wesentlich von dem aus Plasma isolierten Faktor XIII : die Molekulargewichte, die Untereinheiten sowie die Kohlenhydrat- und Aminosäurenzusammensetzung sind verschieden. Immunologisch zeigen die fibrinstabilisierenden Faktoren aus Plasma und Thrombozyten eine gewisse Übereinstimmung. Beide haben eine Antigendeterminante, die mit dem aktiven Zentrum in Zusammenhang stehen muß, gemeinsam; die gegen diesen Antigenbezirk gerichteten Antikörper hemmen die fibrinvernetzende Aktivität beider Faktoren. Eine zweite im Plasma-Faktor XIII vorkommende Antigendeterminante fehlt im Faktor XIII aus Thrombozyten.

Evolutionary origins of the placental expression of chromosome 19 cluster galectins and their complex dysregulation in preeclampsia

INTRODUCTION

The dysregulation of maternal-fetal immune tolerance is one of the proposed mechanisms leading to preeclampsia. Galectins are key regulator proteins of the immune response in vertebrates and maternal-fetal immune tolerance in eutherian mammals. Previously we found that three genes in a Chr19 cluster encoding for human placental galectin-13 (PP13), galectin-14 and galectin-16 emerged during primate evolution and may confer immune tolerance to the semi-allogeneic fetus.

MATERIALS AND METHODS

This study involved various methodologies for gene and protein expression profiling, genomic DNA methylation analyses, functional assays on differentiating trophoblasts including gene silencing, luciferase reporter and methylation assays. These methods were applied on placental specimens, umbilical cord blood cells, primary trophoblasts and BeWo cells. Genomic DNA sequences were analyzed for transposable elements, transcription factor binding sites and evolutionary conservation.

RESULTS AND DISCUSSION

The villous trophoblastic expression of Chr19 cluster galectin genes is developmentally regulated by DNA methylation and induced by key transcription factors of villous placental development during trophoblast fusion and differentiation. This latter mechanism arose via the co-option of binding sites for these transcription factors through promoter evolution and the insertion of an anthropoid-specific L1PREC2 transposable element into the 5' untranslated region of an ancestral gene followed by gene duplication events. Among placental Chr19 cluster galectin genes, the expression of LGALS13 and LGALS14 is down-regulated in preterm severe preeclampsia associated with SGA. We reveal that this phenomenon is partly originated from the dysregulated expression of key transcription factors controlling trophoblastic functions and galectin gene expression. In addition, the differential DNA methylation of these genes was also observed in preterm preeclampsia irrespective of SGA.

CONCLUSIONS

These findings reveal the evolutionary origins of the placental expression of Chr19 cluster galectins. The complex dysregulation of these genes in preeclampsia may alter immune tolerance mechanisms at the maternal-fetal interface.

Cloning, sequencing, structural and molecular biological characterization of placental protein 20 (PP20)/human thiamin pyrophosphokinase (hTPK)

Full-length cDNAs of placental protein 20 (PP20) were cloned by screening a human placental cDNA library, which encode a 243 amino acid protein, identical to human thiamin pyrophosphokinase (hTPK) as confirmed by protein sequence analysis. Genomic alignment showed that the PP20/hTPK gene contains 9 exons. It is abundantly expressed in placenta, as numerous EST clones were identified. As thiamine metabolism deficiencies have been seen in placental infarcts previously, these indicate that PP20/hTPK may have a role in placental diseases. Analysis of the 1kb promoter region showed numerous putative transcription factor binding sites, which might be responsible for the ubiquitous PP20/hTPK expression. This may also be in accordance with the presence of the protein in tissues responsible for the regulation of the exquisite balance between cell division, differentiation and survival. TPK activity of the purified and recombinant protein was proved by mass spectrometry with electrospray ionization. By Western blot, PP20/hTPK was found in all human normal and tumorous adult and fetal tissues in nearly equal amounts, but not in sera. By immunohistochemical and immunofluorescent confocal imaging methods, diffuse labelling in the cytoplasm of the syncytiotrophoblasts and weak staining of the trophoblasts were observed, and the amount of PP20/hTPK decreased from the first trimester to the end of gestation. A 3D model of PP20/hTPK was computed (PDB No.: 1OLY) by homology modelling. A high degree of structural homology showed that the thiamin binding site was highly similar to that of the mouse enzyme, but highly different from the bacterial ones. Comparison of the catalytic centre sequences revealed differences, raising the possibility of designing new drugs which specifically inhibit bacterial and fungal enzymes without affecting PP20/hTPK and offering the possibility for safe antimicrobial therapy during pregnancy.

Homology modelling and molecular dynamics studies of human placental tissue protein 13 (galectin-13)

The primary structure of the newly sequence analysed placental tissue protein 13 (PP13) was highly homologous to several members of the beta-galactoside-binding S-type lectin (galectin) family. By homology modelling, the three-dimensional structure of PP13 was built based on high-resolution crystal structures of homologues and also their characteristic 'jellyroll' fold was found in the case of PP13. Our model has been deposited in the Brookhaven Protein Data Bank. By multiple sequence alignment and structure-based secondary structure prediction, we underlined the structural similarity of PP13 with its homologues. The secondary structure of PP13 was identical with 'proto-type' galectins consisting of a five- and a six-stranded beta-sheet, joined by two alpha-helices, and galectins' highly conserved carbohydrate-recognition domain (CRD) was also present in PP13. Of the eight consensus residues in the CRD, four identical and three conservatively substituted were shared by PP13. By docking simulations PP13 possessed sugar-binding activity with highest affinity to N-acetyllactosamine and lactose typical of most galectins. All ligands were docked into the putative CRD of PP13. Based on several lines of evidence discussed in this paper demonstrating that PP13 is a novel galectin, PP13 was also designated galectin-13. These computational results provide some new insights into the possible role and importance of PP13 in various processes of the human body and can be of help in the initial steps of further functional research.

Molecular cloning and characterization of placental tissue protein 18 (PP18a)/human mitochondrial branched-chain aminotransferase (BCATm) and its novel alternatively spliced PP18b variant

Five different insert-length cDNAs encoding for soluble placental tissue protein 18 (PP18) variants were isolated by screening a human placental cDNA library using monospecific anti-PP18 serum. Sequence analysis of the longest clone showed that the insert contains an open reading frame encoding for a 392 residue-long protein with a 27 amino acid mitochondrial targeting sequence. The mature protein-designated PP18a-is 41.264 kDa consisting of 365 residues and is identical to the previously isolated and characterized PP18 antigen described in 1985. We also found a new, alternatively spliced cDNA encoding for a 300 residue-long, 33.776 kDa protein, which was designated PP18b. Alignment search of the protein databank showed that PP18a is almost entirely identical to the human mitochondrial branched-chain aminotransferase, while PP18b is its newly discovered splicing variant. We detected the two PP18 variants in normal adult and fetal human tissues besides the mitochondrial (only PP18a) and cytosolic (only PP18b) fractions of term placenta with chemiluminescence Western blot analysis. The 41 kDa PP18a variant was expressed ubiquitously, while the 33 kDa PP18b variant was found in smaller amounts in nearly all tissues. Trace amounts of the variants were present in the sera of non-pregnant healthy controls, as well as in pregnant women, but there was no real change in serum levels during pregnancy. In conclusion, PP18 variants are not specific for the placenta. Aminotransferase activity of placental origin PP18 antigens was verified by structural analysis and by a coupled branched-chain aminotransferase/glutamate dehydrogenase assay.

Overexpression of placental tissue protein 17b/TIP47 in cervical dysplasias and cervical carcinoma

In our previous Western- and Northern-blot investigations, high over-expression of placental protein 17b/TIP47 was detected in extracts of human cervical carcinoma tissues compared to normal conditions of the cervical tissue. PP17b serum levels were also elevated in untreated cervical carcinoma patients compared to healthy controls. In the present study, the expression pattern of PP17 proteins was investigated in various cervical dysplasias and in cervical carcinoma tissue specimens by the streptavidin-biotin immunoperoxidase technique using PP17-specific antiserum. In normal third-trimester human placentas, which served as positive controls, mainly cytoplasmic PP17 immunostaining of syncytiotrophoblasts and chorionic trophoblasts was observed. Normal human uterine cervical squamous and glandular epithelia were negative or weakly positive, while in low grade dysplasias (CIN I-II) only the cytoplasms of dysplastic cells were weakly positive or positive; in high grade dysplasias (CIN III/ISC) cytoplasms of the dysplastic cells were strongly positive. Normal and superficial cells in the differentiated zones were negative in all tissue specimens. In cases of invasive epithelial cervical carcinomas, small basal-type tumour cells were mostly negative whilst cells with squamous differentiation were strongly positive for PP17. Our hypotheses for this newly detected phenomenon are briefly discussed.

Glycodelins

Glycodelins are 28 to 30-kD glycoproteins synthesized in various glands, notably those of the male and female reproductive organs. Depending on the site of origin, the same protein backbone is glycosylated in different ways, yielding glycodelins with different biological actions. Thus, human endometrium-derived glycodelin-A is temporally expressed in the latter half of the menstrual cycle, consists of unique sialylated and fucosylated lacdiNAc oligosaccharide sequences, and inhibits sperm-egg binding. By contrast, glycodelin-S from seminal vesicles has no such oligosaccharide sequences and no contraceptive activity. Glycodelin-A also has potent immunosuppressive properties, and its chemically modified forms inhibit transmission of HIV in vitro. Studies are reviewed suggesting that glycoforms dictate the function of human glycodelins, and that some of the oligosaccharide recognition sites present in the human gametes and immune cells have converged.

Isolation and sequence analysis of a cDNA encoding human placental tissue protein 13 (PP13), a new lysophospholipase, homologue of human eosinophil Charcot-Leyden Crystal protein

Expression of placental tissue protein 13 (PP13) in different human tissues was investigated by chemiluminescence Western blot analysis using monospecific anti-PP13 serum. In term placentae we detected a 16 kDa single protein band immunochemically identical to the purified PP13 antigen. After investigation of 26 types of human fetal and adult tissue, PP13 was also found in certain other normal and tumorous tissue extracts. It is not secreted into circulation as we could not find PP13 in sera of pregnant women. A full length cDNA with 578 bp insert was isolated by screening a human placental cDNA library with anti-PP13 serum. The open reading frame of the cDNA encodes for a 139-residue-long protein with a predicted molecular mass of 16.118 kDa, identical to the previously isolated and characterized PP13 antigen described in 1983. By alignment search of the protein databank PP13 is highly homologous (69 per cent) to the 16.5 kDa human eosinophil Charcot-Leyden Crystal protein, a unique dual-function lysophospholipase, a member of the beta-galactoside binding S-type animal lectin superfamily. Northern blot analysis revealed a 600 bp PP13 mRNA, detected only in placental tissue from 16 types of human healthy adult tissue. Lysophospholipase activity of PP13 was confirmed by(1)H and(31)P nuclear magnetic resonance (NMR) measurements.

Is placental tissue protein 17b/TIP47 a new factor in cervical cancer genesis?

We identified novel members of the placental tissue protein 17 (PP17) protein family which consists of different-size variants of PP17; cDNAs of PP17a and PP17b variants have also been cloned and sequence analyzed. By Western-blot analysis in cervical carcinoma tissues we found overexpression of PP17b. Compared to healthy controls a mean five-fold increase in the amount of PP17b was also detected in the sera of untreated cervical carcinoma patients, which declined after radical operations. In our recent findings, in sera of inoperable cervical carcinoma patients, we also found elevated PP17b levels which did not change after irradiation. By Northern-blot analyses we confirmed PP17b overexpression in cervical carcinoma tissues and also the alternative splicing of PP17 mRNAs in various normal human tissues. Presently, the amino acid sequence of TIP47--a mannose-6-phosphate receptor cargo selection device--turned out to be identical to that of PP17b. Due to its oncodevelopmental function, PP17b/TIP47 is more than likely to be connected to HSV-2 infection, which is probably one of the main etiopathogenic agents of cervical carcinoma along with the HPV virus, and may open a new trend in the research of pathological processes in human uterine cervical cancer.

Cloning and sequencing of human oncodevelopmental soluble placental tissue protein 17 (PP17): homology with adipophilin and the mouse adipose differentiation-related protein

Using a monospecific anti-PP17 antiserum, we detected 4 different molecular-weight PP17 immunoreactive proteins (31,500 kD PP17a, 48, 000 kD PP17b, 60,900 kD PP17c and 74,000 kD PP17d) in different normal adult and fetal human tissues, and in term placenta, by chemiluminescence Western blot analysis. These proteins are overexpressed in cervix carcinoma tissue. Furthermore, increased amounts of PP17b are secreted into the circulation in cervix carcinoma patients; after radical surgery, PP17b serum levels are decreased, and the protein probably has an oncodevelopmental significance. cDNAs were isolated from a human placental cDNA library with the monospecific anti-PP17 antiserum. Sequence analysis of the clones showed that they encode for the 251 residue long PP17a variant, which is identical to the previously isolated and characterized PP17 antigen described in 1983. An alignment search of the protein databank showed that PP17a is homologous to human adipophilin and mouse adipose differentiation-related protein. PP17c turned out to be a dimer of PP17a, while PP17b and PP17d immunoreactive proteins recently detected on Western blots require further investigations.

Cloning and sequence analysis of cDNAs encoding human placental tissue protein 17 (PP17) variants

Using monospecific anti-PP17 serum with chemiluminescence Western-blot analysis, we detected different molecular-mass variants of human soluble placental tissue protein 17 (PP17) in different normal adult and fetal human tissues besides term placenta. 13 cDNAs with three different insert lengths encoding PP17 variants were isolated by screening a human placental cDNA library. Sequence analysis of the shortest clones showed that the inserts contain the same open reading frame encoding PP17a variant (28,129 kDa) consisting of 251 residues, which is identical to the previously isolated and characterised PP17 antigen described in 1983. The ubiquitous PP17b variant is encoded by longer clones and contains 434 residues with a predicted molecular mass of 47,208 kDa. Compared to normal conditions, these newly discovered PP17 variants are overexpressed in cervix carcinoma tissue, as are their three different-size messenger RNAs in HeLa cell line. Increased amounts of PP17b are secreted into the circulation in cervix carcinoma patients. We also observed a typical elevation in serum levels of PP17 variants during healthy pregnancy. An alignment search of the protein databank showed that PP17a and PP17b are homologous to adipose tissue differentiation and lipid-droplet-associated proteins: human adipophilin, mouse adipose differentiation-related protein and rat perilipin A and B.

Immunohistochemical localization of pregnancy-related placental protein 4 in human placenta, umbilical cord and adult human female genital tissues

Placental protein 4 (PP4) is a soluble placental tissue protein which was isolated from human placenta. The aim of the present study was to demonstrate the localization of cells containing PP4 in human placenta and in various female genital tissues under normal conditions. PP4 immunoreactive structures were demonstrated by using the peroxidase-antiperoxidase immunohistochemical technique. The samples were obtained from normal human placenta, umbilical cord, uterine cervix, endometrium, ovary and vulva. The most differentiated trophoblastic cells, the syncytiotrophoblasts, as well as the intermediate trophoblast cells contained PP4. PP4 immunoreactivity was present in umbilical cord as well. Occasionally PP4 was detected in normal ovarian, endometrial or vulvar tissue samples. Cervix and myometrium were free of PP4 immunoreactive material. PP4 staining was cytoplasmic. Our findings indicate that PP4 cannot be considered specific for the placenta since it is present in some human adult tissues as well.

Cardiovascular actions of the furoxan CAS 1609, a novel nitric oxide donor

1. This study examines the cardiovascular effects of CAS 1609 (4-hydroxymethyl-furoxan-3-carboxamide) in vitro as well as in vivo in various animal models. 2. CAS 1609 relaxed guinea-pig pulmonary artery strips without endothelium with IC50-values of 0.9 microM (phenylephrine contracted) and 15 microM (KCl-depolarized). This effect was inhibited by oxyhaemoglobin. In these arteries CAS 1609 significantly increased (+192%) guanosine 3':5'-cyclic monophosphate levels, which indicates that the compound acts as a donor of nitric oxide (NO). 3. In the anaesthetized pig, CAS 1609 (0.3-1.0 mg kg-1, i.d.) significantly lowered blood pressure and left ventricular end-diastolic pressure. Left ventricular contractility was slightly reduced and heart rate remained almost unchanged. 4. In anaesthetized dogs, i.v. or i.d. administration of CAS 1609 (0.3-3.0 mg kg-1) decreased, in a dose-related fashion, preload and afterload of the heart, cardiac output, left ventricular work and myocardial oxygen consumption. This haemodynamic profile is similar to that of known NO-donors. 5. In anaesthetized dogs with acute heart failure due to intracoronary injection of microspheres, CAS 1609 (0.3 mg kg-1, i.v.) improved the haemodynamic condition and reduced mortality by 80%. 6. In conscious dogs, oral treatment with a dose of 0.5 mg kg-1 given twice daily at 07 h 00 min and 19 h 00 min (each dose had a duration of action > or = 12 h) for 5 days showed no signs of tolerance to the haemodynamic effects of the drug. 7. All these data indicate that CAS 1609 is a potent, long-lasting orally active donor of NO, devoid of tolerance development.

Antiischemic effects of pirsidomine, a new nitric oxide donor

The antiischemic effect of pirsidomine (CAS 936 (3-(cis-2,6-dimethylpiperidino)-N-(4-methoxybenzoyl))-sydnon imine), a new nitric oxide donor, was investigated in a model of myocardial infarction in the dog. Dogs were anaesthetised, thoracotomized, and the left descending coronary artery was occluded for 6 h. Pirsidomine was given intraduodenally (i.d.) at the dose of 1.0 mg/kg to 11 dogs 30 min prior to coronary occlusion. Eleven dogs received the solvent i.d. and served as controls. Pirsidomine administration completely prevented the increase in left ventricular end-diastolic pressure and pulmonary artery pressure induced by the coronary occlusion and resulted in a marked decrease in systolic and diastolic blood pressure, cardiac output, left ventricular contractility, left ventricular work and left ventricular oxygen consumption. Additionally, pirsidomine completely prevented the occlusion-induced increase in flow in the non-occluded circumflex coronary artery. Regional blood flow measurements (with radioactive microspheres) revealed that pirsidomine induced a significant reduction in blood flow in the non-ischemic areas (both epi- and endocardial) but in the course of the ischemia, significantly increased flow in the ischemic epicardial areas. Infarct-size (triphenyltetrazolium chloride technique) in control dogs was 45% of the area at risk, but only 26% (P < 0.05) in pirsidomine-treated dogs. Thus, pirsidomine had a marked antiischemic effect in this model. This was probably due to the hemodynamic unloading of the heart as well as to redistribution of blood from the non-ischemic to the ischemic areas of the myocardium.

Immunohistochemical localization of pregnancy-related placental protein 4 in nontumorous tissues and in gynecological tumors

The aim of the study was to demonstrate the localization of placental protein 4 (PP4) in different nontumorous and tumorous tissues originating from the female genital tract. PP4 immunoreactivity was demonstrated using the peroxidase-antiperoxidase immunohistochemical technique. Tissue samples were obtained from the cervix and body of the uterus, ovary, vulva and from gestational trophoblastic tumors. PP4-positive cells were present in nontumorous tissues with various pathologic findings, and in many but not all benign gynecological tumors. Similar numbers of PP4-positive cells were located in malignant and benign gynecological tumors; however, PP4 staining intensity was greater in the malignant lesions. PP4-positive cells were found in hydatidiform moles and in choriocarcinoma. PP4 was distributed mainly in the cytoplasm, but it was also bound to the cell membrane. We conclude from these studies that PP4 is located in a variety of benign and malignant cells of the female genital tract and that these cells may be the source of plasma PP4 found in patients with these conditions.

New NO-donors with antithrombotic and vasodilating activities, II: 3-alkyl-N-nitroso-5-sydnone imines

Fifteen 3-alkyl-, four 3-cycloalkyl-N-nitroso-5-sydnone imines and five 3-alkyl-N-nitro-5-sydnone imines were synthesized and their ability to inhibit platelet aggregation induced by collagen (Born-test) was studied in vitro. Dependent on the chemical structure, the IC50-values for the inhibition of platelet aggregation were in the range of 0.2-140 mumol/L. It is suggested that this scale reflects different binding properties of the nitrosimines with respect to the platelet membrane. Highest activities were observed for the 3-hexyl (2f) and the 3-cyclohexyl (2p) derivative. Three nitrimines (3e, 3f, 3i) also showed IC50 values below 10 mumol/L. For the nitrosimines 2a, 2f, and 2m antithrombotic activity was demonstrated in vivo. They inhibited laser induced arterial thrombosis in anesthetized rats up to 70% two h after oral administration. In conscious renal-hypertensive dogs, the decrease in systolic blood pressure and left ventricular enddiastolic pressure suggests an antianginal activity of the compound 2a similar to that of molsidomine (M). The smoother onset and the longer duration of action of the new compound as compared to M could be a significant advantage of 2a in the therapy of angina pectoris.

The development of an enzyme immunoassay for placental tissue protein 17 (PP17) and its clinical significance

We developed an enzyme immunoassay (EIA) for placental protein 17 (PP17) using avidin biotin binding, and measured the serum-PP17 levels of 37 healthy men, 103 nonpregnant women, 48 pregnant women, and 86 patients with gynecologic malignancies. The mean level was 12.8 ng/ml in healthy men and 44.2 ng/ml in nonpregnant women (p < 0.05). The calculated upper limit of normal was 97.8 ng/ml (mean + 2 sigma). The serum PP17 concentration was remarkedly reduced postmenopausally. Pregnant women showed a mean serum level of 19.2 ng/ml, which was significantly lower than that of nonpregnant women. Immunoserological results strongly suggest that PP17 is produced far more in the normal endometrium than in the placentae and decidua. Patients with gynecologic malignancies had obviously lower mean serum PP17 levels (8.3-19.9 ng/ml) than those found in healthy nonpregnant women. Measurement of the serum PP17 concentration might be useful in distinguishing gynecologic malignancies from various normal conditions.

Levels of alpha2 pregnancy-associated glycoprotein in maternal circulation during pregnancy in the mink

This is the first demonstration of alpha 2-pregnancy-associated glycoprotein (alpha 2-PAG) in the mink. Mink alpha 2-PAG exhibits complete immunological cross reaction with dog alpha 2-PAG when analysed in assays employing antisera against canine alpha 2-PAG raised in rabbits. Alpha 2-PAG was quantitated by rocket immunoelectrophoresis in heparin plasma samples obtained from the peripheral circulation of mink during the breeding season. The plasma levels recorded in male mink were significantly lower (23 AU/ml) than the levels recorded in females at any stage of the breeding period. Very early in the breeding season and 2 weeks after delivery the alpha 2-PAG levels were high (> 200 AU/ml) in the circulation of the female mink. Like alpha 2-PAG in the pregnant bitch, mink alpha 2-PAG concentrations reach a local maximum in mid-pregnancy, and a local minimum at term.

Cardiovascular effects of the new nitric oxide donor, pirsidomine. Hemodynamic profile and tolerance studies in anesthetized and conscious dogs

The hemodynamic profile of pirsidomine, a new donor of NO (nitric oxide), was evaluated in dogs. In anesthetized dogs, the intravenous or intraduodenal administration of pirsidomine (0.3-10 mg/kg) decreased dose relatedly the preload and afterload of the heart, total peripheral resistance, cardiac output, left ventricular work and myocardial oxygen consumption. In conscious renal-hypertensive dogs, oral administration of pirsidomine (1.0-10 mg/kg) caused a marked and sustained decrease in systolic blood pressure and left ventricular end-diastolic pressure, which was accompanied by a slight and transient increase in heart rate and contractility. The diastolic blood pressure was affected less than in anesthetized dogs. Similar hemodynamic effects were obtained with M1 (3-(1-(2,6-dimethylpiperidino))-sydnonimine; 0.3-1 mg/kg), the main metabolite of pirsidomine, and with the known NO donor, isosorbide-5-mononitrate (IS-5-MN; 2-10 mg/kg). Tolerance development after repeated administration of pirsidomine and IS-5-MN was also investigated. In anesthetized dogs, repeated intraduodenal administrations of pirsidomine did not attenuate the response whereas tolerance occurred with hemodynamically equieffective doses of IS-5-MN. In conscious dogs, long term oral treatment, three times daily every 8th h for 5 days, revealed tolerance to IS-5-MN, slight or no tolerance to pirsidomine, and no cross-tolerance between the two agents. The results indicate that pirsidomine possesses an antianginal hemodynamic profile similar to that of its main metabolite, M1, and of IS-5-MN. This suggests a common mode of action via the release of NO.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical and ultrastructural investigation of new membrane-associated placental tissue proteins (MP2 A, B, C, D, and E) in gynecologic neoplasms

New membrane-associated placental tissue proteins (MP2 A, B, C, D, and E) were investigated immunohistochemically by avidin-biotin immunoperoxidase technique and immunoelectron microscopy in various gynecologic neoplasms and normal gynecologic tissues. MP2 A and MP2 B were not specific for malignant tumors. MP2 C was present in 67-100% of ovarian carcinomas, 100% of benign dermoid cysts, and 77% of endometrial carcinomas. Except for endocervical adenocarcinomas, MP2 D was hardly detectable in gynecologic malignancies. Although MP2 E was hardly detectable in benign gynecologic tumors, this protein was present in ovarian carcinomas, uterine squamous carcinomas, endocervical adenocarcinomas, and endometrial adenocarcinomas. These results suggest a possible clinical application of these MP2 proteins as a new tumor marker for gynecologic malignancies.

The immunohistochemical localization of new membrane-associated placental tissue proteins (MP2 A, B, C, D, and E) in human and cynomolgus monkey placentae

New membrane-associated placental tissue proteins (MP2 A, B, C, D, and E) were investigated by avidin-biotin immunoperoxidase technique in the human and cynomolgus monkey placentae, decidua and umbilical cords. In human early placentae, MP2 A, B, C, and E were localized mainly in the membrane of villous syncytiotrophoblasts and cytotrophoblasts. Histiocytes in the villous stroma were positive for MP2 A, B, D, and E. In human term placentae, obvious positive staining for MP2 A, B, C, and E was observed in the membrane of villous syncytiotrophoblasts, in the amniotic epithelium, and in the umbilical cord sheath. Histiocytes in the villous stroma were positive for MP2 A, B, C, E, and especially for MP2 D. Importantly, MP2 A, C, and E were positive in polymorphonuclear neutrophils, since most of these common antigens are also carcinoma-associated, suggesting clinical usage of MP2 proteins as a new tumor marker. In the cynomolgus monkey placentae, similar immuno-staining results were obtained. The monkey can thus serve as a experimental model for the investigation of the placental proteins.

CAS 936, a novel syndnonimine with direct vasodilating and nitric oxide-donating properties: effects on isolated blood vessels

Organic nitrates and sydnonimines exert their vasorelaxant activity by a common mechanism of action, i.e., release of nitric oxide (NO) and stimulation of the soluble guanylate cyclase of vascular smooth muscle cells. We wished to investigate the vasodilating activity of the novel sydnonimine CAS 936 in guinea pig isolated pulmonary arteries without endothelium. CAS 936 had no effect on contractions induced by norepinephrine (NE) or by the PGF2 alpha-analogue U46 619, but induced a longlasting relaxation of potassium depolarized arteries and of A23 187-contracted vessels. This effect was concentration-dependent (IC50 approximately 16 microM). Oxyhemoglobin and methylene blue had no inhibitory effect on CAS 936, whereas they inhibited the relaxations induced by SIN-1, a sydnonimine which acts by releasing NO. These results suggest that the vasodilating activity of CAS 936 is not related to NO. On the other hand, in vivo metabolites of CAS 936 inhibited NE- and U46 619-induced contractions. Oxyhemoglobin inhibited this effect. Therefore, we conclude that the CAS 936 molecule possesses a vasodilating activity of its own, whereas the metabolites may function as NO donors. The primary target of the intrinsic vasodilating activity of CAS 936 is very likely the vascular smooth muscle cell membrane. To determine which mechanism of action (NO unrelated or NO related) contributes mainly to the in vivo effects of CAS 936, studies of the metabolic fate of CAS 936 may be crucial.

Immunochemically detected placental proteins and their biological functions

During the last 20 years a systematic search for proteins occurring in human term placenta (afterbirth) has been performed in our laboratory. As a result more than 30 soluble placental proteins and at least 20 different solubilized antigens apparently derived from the placental membranes have been identified by immunochemical methods in extracts from human term placentas. Most of these proteins have already been isolated to purity and characterized by their physicochemical parameters. Specific antisera to these proteins were obtained by immunizing animals with the corresponding purified proteins. They were used detect and localize these antigens by immunochemical methods in the placenta and in other human tissues. Sensitive immunochemical assays have been developed to exactly quantitate the new proteins in body fluids and to find out the diagnostic significance of measurement of these proteins in pregnant women and in patients with tumors and other diseases. Another aim was to elucidate the biological functions of our immunochemically detected proteins. The results obtained thus far are reported.

Initial experience with placental protein 4 (PP-4) as tumor marker in cervical and endometrial cancer

PP-4, a recently characterized glycoprotein from human placenta was studied using a specific double-antibody radioimmunoassay in sera of 130 volunteers, 74 cervical cancer patients and 43 endometrial cancer patients. Elevated levels (greater than 3 micrograms/l) were found in 35 (47.3%) cervical cancer patients and in 18 (41.9%) endometrial cancer patients. Degree of elevation were not correlated with clinical stage, histology, and histological degree of differentiation. 36 patients with cervical cancer and 20 patients with endometrial cancer were monitored on two to seven occasions during four to 50 weeks. Rising, remaining unchanged of falling levels of PP-4 correlated with progression, stabilization or regression of disease 55.5% in patients with cervical and 65.0% in patients with endometrial cancer. During and some months after external telecobalt irradiation therapy wide range of PP-4 levels were observed in some patients. The study suggest that PP-4 can be regarded as a tumor associated protein which most likely can serve as tumor marker in cervical and endometrial cancer.

Secretory endometrial protein PP14 in women with early pregnancy bleeding

The decidualized endometrium produces secretory proteins of which secretory endometrial protein PP14 is the major product during the first trimester of pregnancy. The protein is secreted into the uterine lumen as well as into the peripheral blood. The purpose of this study was to examine whether decidual function, evaluated by the serum concentration of PP14, was different in women with early pregnancy bleeding compared to normal pregnant women. A reference range for serum PP14 was established on the basis of single samples from 236 normal pregnant women with ultrasonically confirmed gestational age. All the women were delivered of a normal child at term. The study comprised 128 pregnant women admitted because of vaginal bleeding between 6 and 18 weeks gestation. At ultrasonography, intrauterine fetal heart activity was either present or was confirmed at a subsequent examination. No difference was found in the serum level of PP14 compared to that in normal pregnancies, but women with vaginal bleeding and depressed PP14 levels appeared to have a 5-fold higher risk of preterm delivery than women with bleeding and normal PP14 levels.

Identity between the placental protein PP10 and the specific plasminogen activator inhibitor of placental type PAI-2

The highly specific plasminogen activator inhibitor of placental type, PAI-2, occurs in the placenta in a low molecular mass form of 46.6 kDa, and in pregnancy plasma in a (possibly glycosylated) high molecular mass form of 60 kDa. Extensive knowledge is available about the functional properties of PAI-2 as a plasminogen activator inhibitor and about its molecular biology and regulation. Of the several placenta proteins (PP) isolated, one of them, PP10, has a molecular mass of 48 kDa and its occurrence in malignancy and in complications during pregnancy has been the topic of a number of studies, though its properties and physiological significance are unknown. The present findings constitute evidence of immunological identity between PP10 and PAI-2. The sections of the amino acid sequence of PP10 analysed here were found to have identical counterparts in the sequence of the low molecular mass form of PA1-2, but in several preparations PP10 was found to occur in an inactive two-chain form due to cleavage of an Arg-Thr bond, the two peptide chains being linked to each other by a disulphide bridge. The cleavage site is identical to that observed in the reaction between PAI-2 and urokinase. The results make it possible to coordinate and correlate the findings of many separate studies and our own observations on PP10 and PAI-2.

Isolation and characterization of membrane-associated placental proteins

Membrane-associated proteins (MPs) of the human term placenta (afterbirth) were obtained by extracting the insoluble part of the tissue with solubilizing agents, after the soluble material had been removed by washing with saline. The insoluble residue was subsequently exhaustively extracted first with the nonionic detergent Triton X-100 and then with 6 M urea. In the Triton extract eleven new different membrane-associated antigens could be detected by immunochemical methods; they were designated as MP2A to MP2L. One of these proteins (MP2C) was found to be immunochemically identical with the already described soluble placental protein PP21 [3]. MP1 another antigen detected in the Triton extract later was identified as heart stable alkaline phosphatase. In the urea extract eight different membrane-associated antigens could be identified by immunochemical methods; they were designated as MP3 to MP10. MP3 later was found to be immunochemically identical with laminin. All these membrane-associated proteins have now been isolated to purity and characterized by their physico-chemical properties. Specific antisera to the new proteins were obtained by immunizing animals with the corresponding purified proteins. They were used to detect and quantitate the new proteins in extracts of placentas and other human tissues by immunochemical methods such as gel diffusion tests. The immunocytochemical localization of the new proteins as well as measurement of their concentrations in body fluids by sensitive radioimmunoassays or enzyme immunoassays are presently under investigation.

Isolation and characterization of five new soluble placental tissue proteins (PP22, PP23, PP24, PP25, PP26)

Five new soluble placental tissue proteins (PP22, PP23, PP24, PP25, PP26) were isolated to purity from saline extracts of human term placentas and characterized by their physico-chemical properties. Specific antisera to the new proteins were obtained by immunizing animals with the corresponding purified proteins. They were used to detect and quantitate the new proteins in extracts of placentas and other human tissues by immunochemical methods such as gel diffusion tests. The immunohistochemical localization of the new proteins as well as measurement of their concentrations in body fluids by sensitive radioimmunoassays are presently under investigation.

Placental protein 4 as a possible tumor marker in ovarian tumors

Placental protein 4 (PP-4), a recently characterized glycoprotein from human placenta, was studied using a specific double-antibody radioimmunoassay in sera of 130 volunteers, 76 ovarian tumor patients and in ovarian tumor cyst fluid and ascites of 21 patients. Elevated levels (greater than 3 micrograms/l) were found in 45 of 52 ovarian cancer patients (86.5%). PP-4 levels correlated significantly with staging. 31 patients with malignant ovarian tumor were monitored on 2-9 occasions during 5-82 weeks. Rising or falling levels of PP-4 correlated with progression or regression of disease in 25 of 31 instances (80.6%). Elevated levels were found in 10 of 24 benign and borderline ovarian tumors. Elevated PP-4 level does not indicate malignancy in each case. PP-4 can be regarded as tumor-associated antigen and an tumor marker in oncological practice.

Enzyme immunoassay for placental protein 4 (PP4) and its possible diagnostic significance in patients with genital tract cancer

We have established an enzyme immunoassay for placental protein 4 (PP4), by using avidin-biotin binding reaction, and set its normal range below 10.9 ng/ml (mean + 2 sigma). Throughout the menstrual cycle, the serum PP4 profile was similar to that of serum progesterone. In the follicular and ovulatory phase, PP4 remained relatively low, with the mean levels of 1.5 ng/ml and 1.8 ng/ml, respectively. In the luteal phase, the mean level was 3.2 ng/ml. In normal pregnancy, serum PP4 levels were low irrespective of gestational age, with a mean level of 3.0 ng/ml. There was only one case in which the serum PP4 level over 10.9 ng/ml. Mean serum PP4 levels and the frequencies of elevated serum PP4 levels were respectively 6.3 ng/ml and 11% in patients with benign ovarian neoplasms, 4.7 ng/ml and 6% in patients with endometriosis, and 5.5 ng/ml and 18% in patients with uterine myomata. The frequency of raised PP4 levels was 48% and the mean value was 13.3 ng/ml in patients with endometrial carcinoma, and the values were 44% and 13.4 ng/ml respectively in patients with cervical carcinoma. In patients with ovarian malignancy, the respective values were 15% and 7.0 ng/ml. The results did not relate to clinical stages of disease (FIGO), while the frequencies of elevated serum PP4 in patients with uterine carcinoma was over 40% in stage I diseases. Compared with other tumor markers such as carcino-embryonic antigen (CEA), tissue polypeptide antigen (TPA) and cancer antigen 125 (CA125), PP4 seems to be more promising as a marker of endometrial carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Cloning and expression of a cDNA encoding human placental protein 11, a putative serine protease with diagnostic significance as a tumor marker

The placental protein 11 (PP11) can act as a tumor marker because of its specific association with various forms of cancer. A lambda gt11 cDNA library prepared from human placenta was screened with a polyclonal anti-PP11 antiserum. Out of 10(6) independent clones, only one clone reacted with the anti-PP11 antiserum. The isolated cDNA coded only for the carboxy-terminal part of PP11 and was subsequently used to rescreen a lambda gt10 placental cDNA library. Two cDNA clones out of 10(6) screened were identified encoding the entire protein of 369 amino acids, including a typical hydrophobic signal sequence of 18 amino acids. Expression of the PP11 cDNA coding sequence in Escherichia coli resulted in the synthesis of a protein with the expected size which can be specifically immunoprecipitated with anti-PP11 antiserum. Fractionation experiments revealed that two forms of the protein are present in the bacterial cell: a higher-molecular-weight form of approximately 42 kD in the cytoplasm and a smaller-molecular-weight form of approximately 42 kD in the periplasm. This result indicates that PP11 can be synthesized in E. coli and is process by removal of the hydrophobic signal sequence. Both the placental and the processed recombinant PP11 protein exhibit a protease activity.

Cloning and prokaryotic expression of a biologically active human placental aldose reductase

cDNA clones coding for human aldose reductase (AR) were isolated by antibody screening of a placental lambda gt11 cDNA library. The cDNA comprises the entire coding region and has a total length of 1,394 bp. The sequence deduced from the open reading frame encodes a protein of 316 amino acids and its amino acid composition is identical to the placental protein 9 (PP9), whose isolation and characterization were described by Bohn et al. (1982). The amino acid sequence of the placental human AR shows high homology to the rat AR; both proteins belong to the same protein superfamily as human liver AR, frog lens rho-crystallin, and bovine lung prostaglandin F synthase. Northern blot hybridization analysis revealed a size for the AR mRNA of approximately 1,500 bases. In addition to the full-length cDNA, one lambda gt11 clone was isolated which carries a putative intron of 597 bp at nucleotide position 754, corresponding to amino acid position 247. Expression of the AR cDNA in Escherichia coli resulted in the synthesis of a protein with a molecular weight of approximately 35 kD which can be immunoprecipitated specifically with antiserum raised against PP9. Despite the absence of a typical signal sequence, the human aldose reductase is partially translocated into the periplasm of the E. coli cells, where it is present in an enzymatically active form.

Concentration of placental protein 19 in body fluid and placental tissues

Placental protein 19 (PP19) is one of the new placental tissue proteins identified in extracts from human term placenta by Bohn and Winkler. We measured the PP19 concentration in body fluids and placental tissue by radioimmunoassay; the minimum detectable dose of standard was 1.5 ng/ml. Although ethylene diamine tetraacetic acid (EDTA-2K) inhibited the immunoreaction between PP19 (225/242) and anti-PP19 antibody (632 ZA), the PP19 concentration did not differ between serum and heparin and sodium citrate plasmas. The serum PP19 concentration was increased by hemolysis. In blood cell fractions separated by the Ficoll-Paque/Macrodex method, polymorphonuclear leukocyte fraction contained the highest PP19 concentration. The circulating serum PP19 concentration was 4.5 +/- 1.1 ng/ml (mean +/- standard deviation) in the proliferative phase (n = 8) and 5.1 +/- 1.6 ng/ml in the secretory phase (n = 7) for nonpregnant women, and 4.6 +/- 2.2 ng/ml from men (n = 12). Seminal plasma (n = 8) contained 212.2 +/- 99.7 ng/ml. The maternal serum PP19 concentration in 291 normal pregnancies increased from 6.2 ng/ml (median) at 6-7 weeks of gestation to 34.1 ng/ml at 38-39 weeks. The mean PP19 concentration was higher in amniotic fluid and retroplacental blood, but lower in umbilical cord blood than that in circulating maternal serum. In hydatidiform mole, vesicular fluid contained high PP19 concentration (1154.6 +/- 659.5 ng/ml), although these maternal serum concentration was not statistically higher than normal range. The chorionic villous trophoblast contained more PP19 than decidua, chorion, and amnion. These results suggest that PP19 has an extraplacental source, even though the chorionic villous trophoblast may be the main source throughout pregnancy.

Elevated sera levels of SP-1 induced by chemotherapy in patients with metastatic gestational trophoblastic diseases

6 patients with invasive mole and 5 patients with choriocarcinoma were treated from 1983 till 1986. Serum samples were analyzed by simultaneous determining of pregnancy-specific beta-1-glycoprotein (SP-1) using enzyme-linked immunosorbent assay (ELISA) and beta subunit of human chorionic gonadotropin (beta-hCG) using Serono radioimmunoassay kit. In 2 patients with metastatic gestational trophoblastic disease (MGTD) SP-1 peaks were found during chemotherapy. In patients with MGTD with normalized beta-hCG levels a repeated, temporary elevation of isolated SP-1 levels was observed within some months following chemotherapy. After the last isolated peak of SP-1 the pulmonary metastases disappeared. This phenomenon was interpreted as a consequence of the oncolytic process in the affected tissue. In 1 patient with nonmetastatic choriocarcinoma SP-1 ELISA pseudoreaction was found. To recognize these pseudoreactions, a control plate with nonimmunized rabbit IgG was used, simultaneously with SP-1 determinations.

Comparative study of placental protein 19, human chorionic gonadotrophin and pregnancy-specific beta 1-glycoprotein as immunohistochemical markers for extravillous trophoblast in pregnancy and trophoblastic disease

PP19, a new placental tissue protein, has alpha 1-beta 1 electrophoretic mobility, a molecular weight of 36,500 and 3.9% carbohydrate. To study immunocytochemical PP19 localization in extravillous trophoblast, we obtained formalin-fixed specimens from extravillous tubal pregnancy at gestational weeks (GW) 7-9 (12 blocks); four early intrauterine pregnancies at GW 7-13 (12 blocks); four late pregnancies at GW 28-38 complicated with intramural uterine myoma, placenta increta and abruptio placenta (8 blocks); four invasive complete moles (9 blocks); and seven primary and metastatic gestational choriocarcinomas (12 blocks). Immunohistochemical staining was done for PP19, pregnancy-specific beta 1-glycoprotein (SP1) and human chorionic gonadotrophin (hCG) using the indirect-labeled antibody method [purified PP19 (Lot no. 225/242) and antibody against PP19 (Lot no. 632ZA) prepared by H. Bohn, antibodies against hCG (Behringwerke, Marburg, FRG) and SP1 (Dakopatts, Copenhagen, Denmark)]. In both early and late intrauterine pregnancies, the extravillous syncytiotrophoblastic cell (XST) showed positive staining for hCG and SP1 in the cytoplasm, as well as for PP19, which stained more intensively in the nucleus than in the cytoplasm. The three proteins were not seen in the evtravillous cytotrophoblastic cell (XCT) in the trophoblastic cell column and shell. The interstitial cytotrophoblast-like cell (ICT), which infiltrated into the decidua and myometrium, and their blood vessels, was immunoreactively positive for PP19 but negative for hCG and SP1 with the exception of SP1-positive ICT in the myometrium in late pregnancy. XST and ICT in the endosalpinx of tubal pregnancy stained for all three proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Time-resolved immunofluorometric assay for placental protein 14

A sandwich-type solid phase time-resolved immunofluorometric assay (IFMA) was developed for endometrial protein PP14 (placental protein 14). The assay utilizes affinity-purified polyclonal antibodies for coating the microtiter wells and for labelling with europium (III) chelate. Maintaining specificity, the 0.6 micrograms/l sensitivity of IFMA is over 25 times higher than that of RIA. The immunofluorometric method enables detection and accurate quantitation of PP14 in all those samples in which PP14 is undetectable by RIA. The method is suitable for quantitative measurement of low PP14 levels in serum of postmenopausal and fertile-aged women and men, as well as in follicular fluid. At 14-16 micrograms/l, which is the sensitivity of radioimmunoassay, the intra-assay variation of IFMA is 6.6% and inter-assay variation 11.4%. In postmenopausal women the PP14 levels are 12.7-56.7 micrograms/l, in fertile-aged women 13.7-113.4 micrograms/l, and in men 3.1-53.1 micrograms/l. The levels in preovulatory follicular fluid are 1.2-20.5 micrograms/l. It is concluded that PP14 IFMA is highly sensitive, accurate and suitable for measurement of protein levels undetectable by other currently available methods.

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.

Pregnancy-specific beta 1-glycoprotein: cDNA cloning, tissue expression, and species specificity of one member of the PS beta G family

Pregnancy-specific beta 1-glycoprotein (PS beta G) is a heterogeneous product of the human syncytiotrophoblast, closely related to the CEA-NCA multigene family. In the present study, immunoscreening was carried out with anti-PS beta G antibodies to isolate cDNA sequences from a placental lambda gt11 expression library. One 1847-bp cDNA clone comprising the major portion of the coding sequence of a putative 48-kd peptide was sequenced and characterized. Hybridization of human genomic DNA to the PS beta G sequence revealed a complex pattern of restriction fragments, a finding well in agreement with the assumption that there are several independent PS beta G genes. A variable PstI band was found in human DNA. Transfer blot analysis of human placental RNA identified transcript of 2.2kb and 1.7kb that appear transiently with increasing levels of expression during gestation. No hybridization of PS beta G cDNA to human RNA from liver, kidney, heart, thyroid, and ovary was observed. In analyses of placental RNA from mouse, goat, sheep, and cow, no corresponding transcripts could be detected, and DNA hybridization under low-stringency hybridization conditions resulted in very faint cross-reacting bands, presumably indicating sequences that were scarcely related. However, PS beta G-specific DNA sequencies with similar restriction patterns were found in primates. These results are compatible with the assumption of late evolutionary development of certain PS beta G sequences.

Circulating levels of placental protein 12 and chorionic gonadotrophin following RU 38486 and gemeprost for termination of first trimester pregnancy

First trimester termination of pregnancy was successfully induced in ten patients with RU 38486 followed 2 days later by a prostaglandin (Gemeprost) pessary. Human chorionic gonadotrophin (HCG) values remained unaltered until after the abortion. The levels of placental protein 12 (PP12) showed an immediate and significant fall following RU 38486, then rose to values substantially higher than those at the initial visit after 2 days. These findings show that RU 38486 has a direct inhibitory effect on tissues producing PP12 and confirm the progesterone dependency of this protein.

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.