Affinity of pregnant rat-specific beta 1-globulin for different lectins

The pregnancy-specific beta 1-globulin (SBG) reacts with 10 out of 11 lectins which have affinity to monosaccharides (glucose, mannose, galactose and fucose) and acetylamino sugars. The affinity to ConA and PHA-P was the most pronounced while this protein did not react with the pea lectin. The SBG reactions are specific for every lectin (even with the identical carbohydrate specificity). Peculiarities of the SBG reactions with lectins made it possible to reveal a few forms of this protein which differ in the carbohydrate composition and conformation of carbohydrate radicals.     

The immunohistochemical study of trophoblast beta 1-globulin expression in cancer and in the mucosa of the large intestine]

The expression of pregnancy-specific beta-1-globulin (SP1) was studied in cancer-affected and nonaffected colon mucosa. The antigen was revealed in 19 out of 50 (38%) cases of carcinoma and in 1 out of 4 cases of ulcerative colitis. SP1 was found neither in noncancer colon mucosa nor in transitional mucosa and adenomas. The antigen was detected in the epithelium and stromal macrophages of carcinoma. SP1-positive cells were located mainly in the sites of tumor invasion. The results allow considering SP1 the tumor marker suitable for immunohistochemical diagnosis of colon cancer.     

Human pregnancy-specific beta 1-glycoproteins are coded within chromosome 19.

We have isolated and characterized cDNAs that code for apoproteins having amino acid sequences highly similar to pregnancy-specific beta 1-glycoproteins (PS beta G). cDNAs coding for PS beta Gs, as well as the cDNA clone reported here, are members of the carcinoembryonic antigen (CEA) gene family. The previous localization of CEA-related genes to human chromosome 19, and the high level of DNA sequence conservation in the CEA family, suggested that the PS beta G genes are also located on this chromosome. We demonstrate here that chromosome 19 is indeed the site of PS beta G sequences. Our finding is in contrast to the recently reported indication that pregnancy-specific glycoproteins are encoded in chromosomes X and 6.     

Isolation of human β1A-globulin by modern techniques

1. Human beta(1A)-globulin was isolated from serum by precipitation with ammonium sulphate, gel filtration and electrophoresis in polyacrylamide gel. 2. The product was found by ultracentrifugation, analytical electrophoresis in polyacrylamide gel and two-dimensional immunoelectrophoresis to be of satisfactory quality for further study. 3. The amino acid composition of beta(1A)-globulin was determined. 4. In ordinary dilute buffers near neutrality, beta(1A)-globulin had S(0) (20,w) 6.42s and M 131 000, but some reversible aggregation occurred at lower pH. In neutral 6m-guanidine hydrochloride the molecular weight was not measurably different from that in dilute buffer.     

Physico-chemical properties of trophoblast-specific beta 1-globulin

It has been found that the trophoblast-specific beta 1-globulin [TSG) contains one site of binding to Con A and phytohemagglutinin. The interaction with phytohemagglutinin should be taken into consideration, when studying the immunosuppressive activity of the protein. Additional fractions of the protein with fast anodic electrophoretic mobility and lower molecular weights have been detected after treatment of the trophoblast-specific beta 1-globulin with diethylene triaminopentaacetate. This is indicative of a subunit structure of the glycoprotein molecules.     

Immunochemical study of the specific antigens of human amniotic fluid]

Four specific antigens (trophoblastic beta 1-globulin, placental lactogen, alpha 1- and alpha 2-globulins of human placenta) were identified using antisera to the native amniotic fluid. Five antigens with the mobility of prealbumins, alpha 1-globulins, alpha 2-globulins and beta 2-globulins which bear no resemblance with the previously studied antigens were identified using antisera to the acid fraction of the amniotic fluid. Both the prealbumins and alpha 2-globulin were found in the blood serum of foetuses of different age and of newborn infants; these proteins were absent from the blood serum of pregnant women and donors. They received the names of embryonic prealbumine 1, embryonic prealbumine 2 and embryonic alpha 2-globulin. The protein with the mobility of alpha 1-globulins was found in the amniotic fluid of foetuses and in the blood serum of pregnant women only and received the name of amniotic alpha 1-globulin. The concentration of the antigens in question was studied in the developing foetuses and in the blood serum of pregnant women at different stages of pregnancy.     

Seasonal changes in blood serum protein fractions and in activity of AspAT and AlAT in Arabian brood mares and their foals

In 34 pure breed Arabian horses divided into four groups (Gr. I--10 pregnant mares, Gr. II--7 barren mares, Gr. III--10 foals born in 1981, Gr. IV--7 foals born in 1982) seasonal changes in total blood serum protein, its electrophoretic fractions and the activity of AspAT and AlAT were studied. Seasonal cyclicity was found in all groups in the amount of total serum proteins, and alpha 2- and beta 1-globulin fractions. Cyclicity was found in the level of albumin and activity of AspAT in three groups, not Gr. II, and in gamma-globulin, not Gr. IV. beta 2-globulin and AlAT cyclicity was found in two groups and alpha 1-globulin cyclicity was found only in Gr. II. Out of nine indices studied, cyclicity was found in eight of them in pregnant mares, Gr. I; in seven in older foals, Gr. III; in six in the young foals, Gr. IV; and in five in barren mares, Gr. II.     

Immunohistochemical study of the expression of trophoblastic beta-1-globulin in the gastric epithelium of man in stomach cancer]

The expression of specific-pregnancy beta 1-globulin (SP1) was studied in gastric mucosa with chronic gastritis. The expression of SP1 was revealed in focus of intestinal metaplasia, dysplasia as well as in cover epithelial cells.     

Immunolocalization of alpha and beta chains of human chorionic gonadotropin, placental lactogen and pregnancy-specific beta-glycoprotein in term placenta by a touch preparation method

Touch preparations of human placenta yield cells retaining antigenic reactivity to immunoperoxidase stains for alpha and beta chains of human chorionic gonadotropin, placental lactogen, and pregnancy-specific beta glycoprotein. This method is a rapid and simple alternative to conventional frozen and paraffin-embedded sections for detection of placental peptides.     

Expression of CEA-related genes in the first trimester human placenta

Eight cDNA clones, closely related to the carcino-embryonic antigen gene family, have been isolated from a cDNA library representing genes expressed in the first trimester human placenta. Sequence analysis of one clone shows it to be a pregnancy-specific beta 1-glycoprotein (PS beta G) closely related to three other PS beta G cDNA recently characterised from a term placenta library. The protein encoded by the cDNA is predicted to be less high glycosylated than those reported previously and differs markedly in the C-terminal sequence. The 3' untranslated region of the cDNA is very similar to the equivalent region of beta 1-glycoprotein PS beta G E except that it contains the 12bp repeat sequence found flanking the Alu sequence in CEa and an additional 67bp of sequence that appears to be derived from CEA.     

Serum proteins in the leopard seal, Hydrurga leptonyx, in Prydz Bay, Eastern Antarctica and the coast of NSW, Australia

Blood protein analysis including total serum protein and albumin by chemical methods, fibrinogen estimation and serum protein electrophoresis (SPE) was performed on the leopard seal, Hydrurga leptonyx. The most commonly observed SPE pattern was eight fractions designated albumin, alpha(1a), alpha(1b), alpha(2a), alpha(2b), beta(1), beta(2) and gamma-globulin. Significantly higher total serum protein and albumin concentrations, as determined by chemical methods, and significantly higher alpha(2)-globulin concentrations, determined by SPE, were seen in free-ranging male seals compared to females, whilst significantly higher beta-globulin concentrations were seen in female seals. Season of sampling influenced fibrinogen and beta(2)-globulin concentrations, whereas there were no significant differences in any protein concentrations with moult status. Qualitative comparison of SPE traces of leopard seals in Antarctica with "sick" individuals in NSW, Australia revealed obvious differences, as did quantitative comparison of protein concentrations where differences in alpha(1), alpha(2), beta(1), beta(2), and gamma-globulin concentrations were seen. These findings suggest that SPE is a useful tool for investigating serum proteins in the leopard seal, with applications for the investigation of "sick" individuals and the assessment of variation in homeostasis. This technique could also be used to identify the presence of environmental stressors, subclinical disease and physiological variation within specific seal populations.     

The nucleotide and deduced amino acid sequences of a cDNA encoding a new species of pregnancy-specific beta 1-glycoprotein (PS beta G)

We screened a cDNA library of a human placenta with cDNA for nonspecific cross-reacting antigen, a member of the carcinoembryonic antigen gene family. One of the positive clones, PS34, was found to encode a 426 amino acid protein belonging to pregnancy-specific beta 1-glycoprotein (PS beta G). The mature PS34 protein consisted of domains, N, A1, A2, B2 and C. The domain-N of PS34 showed sequence similarities of 79.8-83.5% to those of the PS beta G members so far reported, indicating PS34 is a new member of PS beta G and also of the carcinoembryonic antigen gene family.     

Tissue-specific retinal proteins in vertebrate evolution

Studies have been made on water soluble antigens of the retina from man and some animals. In the bovine retina, immunochemical analysis reveals, apart from antigens with a broad and narrow interorganic specificity, organospecific alpha 1- and rho-globulins. Immunochemically, the bovine alpha 1-globulin is partially identical with the same protein of the human retina and completely identical to retinal antigens from cattle; rho-globulin is characterized as an interspecific antigen in man and mammals. Molecules of organospecific alpha 1-globulins from the retina of man and some animals (sheep, camel, horse, cow, pig) do not contain the determinants related to the retinal antigens from fishes, reptiles and birds. In human and mammalian retina, acid neurospecific alpha 1-glycoprotein was found which is topical of the cerebral tissue. Organospecific alpha 1-globulin of the bovine retina is located in the pigment epithelium, in the zone of outer and inner photoreceptor segments; organospecific rho-globulin is distributed in the outer synaptic layer of the retina.     

Immunochemical determination of placenta-specific and interorganic antigens in placental extract and blood serum in pregnant rats

It has been demonstrated that placenta extract of rats contains up to 14 antigens. Moreover, 11 of them are interorgan proteins of wide and limited specificity, two antigens (alpha 1- and alpha 2-globulins) are attributed to acute-phase proteins typical for pregnancy. beta 1-Globulin is a specific protein of rat placenta. The content of these antigens in blood serum increases with pregnancy and reaches a maximum toward the delivery; 3-4 days after delivery beta 1-globulin disappears completely from maternal blood, whereas the concentration of acute-phase proteins drops to the initial level.     

The elastase inhibitors of swine serum: isolation and partial characterization of the beta 1-globulin inhibitor and its interaction with elastase

1. The principal elastase inhibitor of swine serum, a beta 1-globulin, has been isolated from serum by ammonium sulfate fractionation, DEAE-cellulose column chromatography and chromatofocusing. 2. The purified beta 1-globulin was homogeneous by immunoelectrophoresis and sodium dodecyl sulfate polyacrylamide gel electrophoresis. Multiple zones (isoinhibitors) were produced on anionic polyacrylamide gels. The mol. wt for the native, elastase-inactivated inhibitor and the beta 1-globulin-elastase complex were respectively, 65,467 and 60,000 and 79,667. The amino acid residue weight was 63,331. 4. The electrophoretic mobilities of the native inhibitor, elastase-inactivated inhibitor and the inhibitor-elastase complex were respectively, -3.4, -3.8 and -2.2 x 10(-5) cm2/V per sec, the isoelectric points were respectively, 4.78-5.28 (major pIs = 5.15, 5.35), 4.63-5.35 (major pI = 5.13) and 6.02-6.2 (major pI = 6.12). 5. The first order dissociation rate constant for the beta 1-globulin-elastase complex (two-fold molar excess of elastase at 37 degrees C) was 1.9 x 10(-3) per sec with complete dissociation in 40.4 min. The dissociation constant for the complex was 1.47 x 10(-7) M. One mol of elastase was bound per mol of the inhibitor. 6. The beta 1-globulin-elastase complex reacts with antibody to either protein moiety.     

Glycosaminoglycans of the aorta in avitaminosis]

It has been shown that pregnancy specific beta 1-globulin (SBG) is found in the rat blood serum on the 6--7th day of pregnancy. SBG reaches the maximum by the end of pregnancy and is not detected already at the 3d--4th day after delivery. The placenta is the site of the SBG snythesis. Other organs of the pregnant rat are not able to incorporate radioactive aminoacids into the protein in vitro.     

Biosynthesis and production of specific beta 1-globulin (SBG) during pregnancy in rats]

It has been shown that pregnancy specific beta 1-globulin (SBG) is found in the rat blood serum on the 5--7th day of pregnancy. SBG reaches the maximum by the end of pregnancy and is not detected already at the 3d--4th day after delivery. The placenta is the site of the SBG synthesis. Other organs of the pregnant rat are not able to incorporate radioactive aminoacids into the protein in vitro.     

Analysis of the size of the carcinoembryonic antigen (CEA) gene family: isolation and sequencing of N-terminal domain exons

Five members of the human CEA gene family [human pregnancy-specific beta 1-glycoprotein (PS beta G); hsCGM1, 2, 3 and 4] have been isolated and identified through sequencing the exons containing their N-terminal domains. Sequence comparisons with published data for CEA and related molecules reveal the existence of highly-conserved gene subgroups within the CEA family. Together with published data eleven CEA family members have so far been determined. Apart from the highly conserved coding sequences, these genes also show strong sequence conservation in their introns, indicating a duplication of whole gene units during the evolution of the CEA gene family.     

Immunochemical identification of human placental organ specific alpha2-globulin and its concentration in amniotic fluid]

An organospecific alpha2-globulin of human placenta was identified with the aid of immunochemical analysis. This antigen differed immunologically from the alpha2- and beta1-globulins of pregnancy, alpha-fetoprotein, placental lactogen, and chorionic gonadotropin. High level of the antigen revealed was found in the placental tissue and the amniotic fluid at the early terms of pregnancy, but its concentration sharply decreased by the time of labour.     

Carbohydrate, protein and glycoprotein metabolism by the guinea-pig liver in chronic metribuzin poisoning

Male guinea-pigs weighing 400-600 g, 8 months old, were given metribuzin directly into the gastric lumen over a period of 30 days (20 animals) or 90 days (20 animals) 6 times a week. In the liver of the poisoned animals, the glycogen level and the AspAT and AlAT activities, while in the serum the total protein and the fractions albumin, alpha 1-globulin and gamma-globulin significantly decreased; serum glucose and the serum fractions alpha 2-globulin and beta-globulin, each showed an increase. The glycogen level in the liver, total protein, glucose as well as the alpha 1 and alpha 2 globulin fractions in the serum showed not appreciable difference between 30 and 90 days of intoxication. After 90 days of metribuzin treatment AspAT and AlAT dropped in the liver and rose in the serum, in comparison to the 30-day values. As to the parameters of glycoprotein metabolism, the intoxicated animals showed a significant decrease and increase in concentration of hexosamines and sialic acids in the liver and serum, respectively. Metribuzin intoxication also cause a significant decrease in activity of glucosamine phosphate isomerase and significant increase in activity of glycosidases in the liver. The results suggest that metribuzin disturbs the metabolism of carbohydrates, proteins and glycoproteins in the guinea-pig liver.