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H Bohn

Publications and source records attributed to H Bohn.

At least 163 records · Page 9Linked to original sources
PubMed1976

[Isolation and characterization of the placental proteil pp1 (author's transl)].

The purification and characterization of the placental protein PP1 is described. The protein has been isolated from an aqueous extract of human term placentae using salt and ethanol fractionation procedures, gel filtration, preparative zone electrophoresis and chromatography on hydroxylapatite. PP1 sediments with 8.4 S and has a molecular weight of 160,000 daltons; it is composed of apparently four identical subunits, which have a molecular weight of 40,000 +/- 2000 daltons and are held together by non-covalent bonds. PP1 is a glycoprotein with a carbohydrate content of 2.7% and has the electrophoretic mobility of an alpha1-globulin. Immunochemical methods were used for the detection and quantitative determination of the protein. PP1 is not found in normal plasma or in erythrocytes; neither could it be detected in sera from pregnant women nor in sera from patients suffering from malignant diseases. PP1 is a tissue protein, but not specific for the placenta; it is also found in other human tissues. The average amount of PP1 extracted from one human term placenta was determined to be around 3 mg. Immunogluorescent studies revealed that the protein is located in the cytoplasma of the syncytium as well as in the stroma of the villi.

Cytoplasm↗
PubMed1976

[Isolation of the pregnancy specific beta-glycoprotein (SP1) and antigen-related proteins by means of immunoadsorption].

Purification of human pregnancy-specific beta1-glycoprotein (SP1) and antigenically related proteins of sub-human primates (chimpanzee, rhesus monkey, cynomolgus and baboon) was achieved by means of an immunoadsorbent technique. The immunoglobulins of a rabbit antiserum to human SP1 were isolated on DEAE-cellulose and coupled to CNBr-activated Sepharose. This immunoadsorbent was used to bind human SP1, respectively monkey proteins immunochemically related to SP1 from placental extract fractions. After extensive washing the proteins were eluted by an acidic glycine buffer. Contaminating serum proteins could be removed by chromatography on hydroxyapatite columns. With this method it was possible to obtain SP1 and the antigenically related proteins of monkeys in good yield and in highly purified form. The proteins thus isolated from human and sub-human primate placentae were compared in their physicochemical and immunochemical properties. The amino acid and carbohydrate compositions of human SP1 and rhesus SP1 have been determined. In a biological test certain inhibitory effect of human SP1 on the mixed leukozyte culture (MLC) could be demonstrated.

Adsorption↗
PubMed1976

[Isolation and characterization of pregnancy associated alpha2 glycoprotein].

A method using immunoadsorbents for the isolation of pregnancy-associated alpha2-glycoprotein (alpha2-PAG) from the extract of human placentae is described. The physical properties and the chemical composition of the purified protein are determined: alpha2PAG sediments with 11,5 S, has a molecular weight of 360 000 daltons and is composed of subunits having a molecular weight of 180000, which are held together by disulfide bonds. The isoelectric point was found to be pH 4,7 and the extinction coefficient (E1%1cm) was determined to be 9,7 at 277 nm. The carbohydrate content of the molecule amounts to 12,1% (hexose 6,0%, hexosamine 3,7%, fucose 0,06%, sialic acid 2,4%). An analysis of the amino acids is reported, too. The purified alpha2PAG was used to determine the absolute concentrations of this protein in a reference standard and in sera.

Female↗
PubMed1976

A serial study of pregnancy proteins in primigravidae.

The plasma concentrations from four 'pregnancy proteins' and three steroid hormones have been measured throughout pregnancy in 15 primigravidae. Two of the proteins, human placental lactogen (HPL) and pregnancy-specific beta1-glycoprotein (PSbetaG), are specific for pregnancy and correlate well with the stage of gestation. It is suggested that measurement of PSbetaG may be useful in assessing feto-placental wellbeing. Neither of the pregnancy-associated proteins, steriod-binding beta-globulin (SBbetaG) and pregnancy-associated alpha2-glycoprotein (alpha2-PAG), correlated with the length of gestation although, near term, plasma alpha2-PAG levels appeared to be related to fetal weight. In addition, no correlation has been demonstrated between placental or fetal weight and any of the pregnancy-specific proteins or steroid hormones studied.

Adult↗
PubMed1975

[Comparative studies on placenta specific proteins in man and subhuman primates (author's transl)].

It is shown that in placentae and partly also in sera from pregnant monkeys (chimpanzee, baboon, rhesus monkey and cynomolgus) proteins occur which are immunochemically related to the human placental specific antigens HPL (human placental locatogen), SP1 (pregnancy specific beta1-glycoprotein), PP5 (placental protein 5) and HSAP (heat stable alkaline phosphatase). The immunochemical and physico-chemical properties of these monkey proteins are compared with those of the corresponding human proteins using gel diffusion test, immuno-electrophoresis, gel filtration and polyacrylamide gel electrophoresis. These antigens also have been localized in the tissue of human and monkey (cynomolgus) placentae by the immunofluorescent technique.

Alkaline Phosphatase↗
PubMed1975

Uteroglobin-like antigen in the male genital tract secretions.

The secretion of the rabbit seminal vesicle has been investigated by morphological and biochemical means. Apical regions of seminal vesicle epithelial cells show highly active protein synthesizing and releasing organells. The secretory proteins released are analysed by disc-electrophoresis and three different immunological procedures. There is evidence for the presence of an uteroglobin-like antigen in seminal vesicle secretion. Comparison with seminal plasma indicated that the uteroglobin-like protein is also present in this fluid. The immunological and electrophoretical identity of rabbit uteroglobin, obtained from the uterus, with "male uteroglobin" is obvious, but molecular-biochemical and biological identity awaits further clarification. The demonstration of uteroglobin-like antigen in the male as in the female points towards new aspects in reproductive and contraceptive research.

Animals↗
PubMed1975

[Antigens of the human placenta (author's transl)].

The immunologic relations between mother, foetus and placenta are discussed and those antigens of the human placenta already characterized by their physico-chemical and immunochemical properties described. In diagnostics the detection and determination of placental proteins is used in pregnancy tests, for the evaluation of placental functions and the detection of malignant diseases. Antibodies to placental antigens have an abortive effect; immunization against placental specific proteins may have implications as an immunologic contraceptive method and for the immunotherapy of choriocarcinoma.

Abortion, Spontaneous↗
PubMed1975

[Isolation and characterization of a high molecular weight placental protein (PPg)(author's transl)].

The isolation and characterization of a high molecular weight protein (PP6) from human placentae is described. The protein which apparently has some steroid-binding properties shows the mobility of an alpha1-globulin and has a molecular weight of around 1 X 10(6) daltons. The molecule is composed of several different subunits with molecular weights ranging from 200,000-35,000 daltons which are held together by non-covalent bonds. Immunofluorescent studies revealed that the placental protein PP6 is localized in the nuclei of the syncytiotrophoblast. But PP6 is not specific for the placenta; this protein is also found in extracts from other human tissues as well as in the erythrocytes. PP6 usually is not present in normal sera but in some cases it could be detected in concentrations ranging from 1-3 mg per 100 ml in sera from pregnant women and in sera from patients with malignant tumors.

Alpha-Globulins↗
PubMed1975

[Isolation and characterization of a 19S-alpha1-glycoprotein from human erythrocytes and its identification as placenta protein PP6].

A high molecular weight protein was isolated from the hemolysate of washed human erythrocytes by a procedure involving ion exchange chromatography, ammonium sulfate fractionation and gel filtration. The purified protein was found to have a sedimentation coefficient of 18,68S and a molecular weight of 8 times 10-5 to 1 times 10-6 daltons. In the presence of sodium dodezylsulfate the molecules are dissociated into at least four different subunits having molecular weights ranging from 12,000 to 30,000 daltons. The protein has the electrophoretic mobility of an alpha-1-globulin and an isoelectric point of pH 4.75. The chemical analysis revealed that the protein is chemical and immunochemical properties the 19S-alpha-1-glycoprotein from human erythrocytes was shown to be identical with the protein PP6 isolated from huamn placentae. The content of this protein in packed red blood cells was determined to be around 50 mg per 100 ml.

Chromatography, Gel↗