CHARACTERIZATION OF THE HUMAN CHORIONIC GONADOTROPHIN FRACTIONS IN PREGNANCY URINE

1978 ◽  
Vol 89 (3) ◽  
pp. 612-624 ◽  
Author(s):  
D. Puett ◽  
A. Kenner ◽  
R. Benveniste ◽  
D. Rabinowitz
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Pregnancy Urine ◽  
In Pregnancy

Distribution of the β-core human chorionic gonadotrophin fragment in human body fluids

1992 ◽  
Vol 135 (1) ◽  
pp. 175-188 ◽  
Author(s):  
S. F. de Medeiros ◽  
F. Amato ◽  
D. Bacich ◽  
L. Wang ◽  
C. D. Matthews ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Granulosa Cells ◽  
Follicular Fluid ◽  
Intramuscular Injection ◽  
Body Fluids ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Pregnancy Urine ◽  
In Pregnancy

ABSTRACT The origins of a fragment of the human chorionic gonadotrophin (hCG) molecule, β-core (βC-hCG) were studied by analysis of βC-hCG concentrations in biological fluids. In addition, the ability of the placenta to produce the fragment and the metabolism of hCG to βC-hCG by human granulosa cells was determined in tissue culture. Finally the conversion of exogenous hCG to βC-hCG was studied in vivo. The fragment was present in pregnancy urine as well as that from premenopausal and postmenopausal subjects. The highest concentrations were found in pregnant women. Ratios of βC-hCG to intact hCG were higher in pregnancy urine when radioimmunoassay (RIA) was used compared with immunoradiometric assay (IRMA) (0·67 and 0·37 respectively). Concentrations of βC-hCG were higher in postmenopausal urine than in premenopausal specimens. A significant amount of a high molecular weight βC-hCG immunoreactive material was found in serum samples after size separation, and the molar ratio of βC-hCG/hCG was estimated as 0·019. Amniotic fluid also contained small quantities of two forms of immunoreactive βC-hCG and the ratio of 0·01 for authentic βC-hCG/hCG increased to 0·026 when the high molecular weight form was considered. Cultured trophoblastic tissue released material with βC-hCG immunoreactivity in the medium and chromatographic separation revealed that the majority of this material was of higher molecular weight compared with the authentic βC-hCG form. βC-hCG was the principal glycoprotein found in follicular fluid after hyperstimulated folliculogenesis and intramuscular injection of 5000 IU hCG. We also demonstrated that 26% of follicular fluid samples (n = 50) were positive for βC-hCG; levels ranged from 5·2 to 23·0 pmol/l (13·1 ±5·7); s.d.) when a specific IRMA was used. The RIA could detect βC-hCG in 48 samples (96%), levels ranging from 7·0 to 28·5 pmol/l (19·4±5·2). Moreover, granulosa cells cultured in the presence of hCG were able to degrade the intact molecule to both high molecular weight and authentic immunoreactive forms of βC-hCG. After gel filtration, material of molecular weight over a wide range and immunoreactive for βC-hCG was present in human seminal plasma. Assaying 74 samples of this fluid by IRMA, βC-hCG was detected in 42 (56·7%), levels ranging between 5·5 and 59·5 pmol/l (24·9± 15·2). Following intramuscular injection of 1500 IU hCG into male volunteers, the levels of βC-hCG in urine increased by approximately 220% during the first 24 h (P= 0·036 for βC-hCG levels at 2 h and 24 h), decreasing thereafter to undetectable levels in the next 72 h. However, in serum, βC-hCG immunoactivity remained under the limit of detection of the assay at all times. We concluded that (1) the βC-hCG fragment is widely distributed in body fluids and a dissociable high molecular weight material immunoreactive for βC-hCG is found in some biological compartments; (2) granulosa-lutein cells are able to degrade intact hCG to a small βC-hCG immunoreactive fragment; (3) trophoblastic cells synthesize and release different size material with βC-hCG immunoreactivity; (4) intramuscular injection of hCG is followed by increased βC-hCG immunoreactivity in urine; and (5) our results support previous studies indicating the peripheral metabolism of intact hCG to βC-hCG as the principal source for this fragment but raise the possibility that a high molecular weight-associated form, probably bound to a specific protein, may be produced by some tissues. Journal of Endocrinology (1992) 135, 175–188

Human chorionic gonadotrophin-like and β-core-like materials in postmenopausal urine

1990 ◽  
Vol 125 (3) ◽  
pp. 477-484 ◽  
Author(s):  
A. H. Akar ◽  
G. Gervasi ◽  
C. Blacker ◽  
R. E. Wehmann ◽  
D. L. Blithe ◽  
...  
Keyword(s):  
Postmenopausal Women ◽  
Tumour Marker ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Acetone Extract ◽  
Small Molecular Weight ◽  
Pregnancy Urine ◽  
Normal Man ◽  
Molecular Weight Form ◽  
In Pregnancy

ABSTRACT In addition to human chorionic gonadotrophin (hCG), the urine of pregnant women contains a small molecular weight form of the hCG-β subunit known as β-core. Human CG-like material has been described in tissues, serum and urine of normal man, particularly in postmenopausal women. We examined different urine preparations from postmenopausal women to determine whether β-core-like material, as well as hCG-like material, could be detected. We studied an acetone extract of a pool of 11 litres of postmenopausal urine, three different commercial preparations of human menopausal gonadotrophins and two commercial preparations of 'pure' FSH. After Sephadex G-100 chromatography of these various postmenopausal urine extracts, fractions were assayed using four assay systems to detect hCG, β-core, LH and FSH immunoreactivities. Human CG immunoreactivity was readily detected in all urinary extracts and it eluted in a position indistinguishable from that of purified hCG. In addition to this hCG-like material, all urinary extracts, except the commercial 'pure' FSH preparations, contained material which reacted in the β-core radioimmunoassay. This β-core immunoreactive material eluted from Sephadex G-100 in a position corresponding to that of purified pregnancy-derived β-core. We conclude that the urine of postmenopausal women contains material resembling the β-core molecule found in pregnancy urine. The origin of this β-core-like material remains to be determined, and its presence will have an impact on the application of urinary β-core as a tumour marker. Journal of Endocrinology (1990) 125, 477–484

COMPARISON OF BIOASSAY AND IMMUNOASSAY OF HUMAN CHORIONIC GONADOTROPHIN IN URINE

1965 ◽  
Vol 50 (3) ◽  
pp. 335-344 ◽  
Author(s):  
Rudi Borth ◽  
Michel Ferin ◽  
Annette Menzi
Keyword(s):  
Biological Activity ◽  
Total Variation ◽  
Regression Line ◽  
Haemagglutination Inhibition ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Factorial Experiment ◽  
Serological Result ◽  
Pregnancy Urine ◽  
Acceptable Agreement

ABSTRACT In 39 samples of pregnancy urine, the concentration of human chorionic gonadotrophin (HCG) was estimated biologically by the ovarian hyperaemia reaction in rats, and serologically by the passive haemagglutinationinhibition technique. The results of the bioassays varied from 3 to 150 IU/ml, those of the immunoassays from 5 to 640 IU-eq./ml, and the correlation between the two (calculated for their logarithms) accounted for only 17 per cent of the total variation (r2 = 0.169, P ≈0.01). If the biological activity were estimated from a serological result and the appropriate regression line, the fiducial interval for P = 0.05 would extend from 17 to 610 per cent of the estimate. In a factorial experiment using three anti-HCG sera, three standard and three sensitizing preparations of HCG, the sensitivity of the serological system (expressed as the endpoint concentration in IU of HCG) varied considerably between the 27 combinations of the 3 factors, but there was no interaction between the latter. From these data and those of other authors, it is concluded that immunoassays based on haemagglutination inhibition cannot replace bioassays in the estimation of HCG, as distinct from its hypothetical metabolites or other related antigens, unless specificity has been demonstrated. The well-documented reliability of serological pregnancy tests is, of course, not in dispute. Attention is drawn to the fact that »statistically significant« correlation does not guarantee analytically acceptable agreement between two methods of assay.

A novel form of ectopic human chorionic gonadotrophin β-subunit in the serum of a woman with epidermoid cancer

1985 ◽  
Vol 107 (3) ◽  
pp. 403-408 ◽  
Author(s):  
S. B. Nagelberg ◽  
L. A. Cole ◽  
S. W. Rosen
Keyword(s):  
Molecular Weight ◽  
Unknown Origin ◽  
Apparent Molecular Weight ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Size Difference ◽  
Gel Chromatography ◽  
Β Subunit ◽  
Peanut Agglutinin ◽  
Pregnancy Urine

ABSTRACT A novel form of free human chorionic gonadotrophin β-subunit (hCGβ) was found in serum from ElBre, a woman with epidermoid carcinoma of unknown origin. ElBre hCGβ was larger than standard (pregnancy urine) hCGβ when analysed by gel chromatography (apparent molecular weight 54 000 vs 44000). This size difference appeared to be due to a larger carboxyterminal extension (CTE) of ElBre hCGβ since thermolysin cleavage of the CTE from standard hCGβ and Elbre hCGβ yielded core products of the same size. Oligosaccharides, O-linked to serine or threonine, were present in ElBre hCGβ, presumably on its CTE as judged by the complete binding of desialylated ElBre hCGβ to immobilized peanut agglutinin (this lectin is specific for terminal galactose linked β1 → 3 to N-acetylgalactosamine, a disaccharide exposed after desialylation of the O-linked oligosaccharides of standard hCGβ). ElBre hCGβ, however, was incompletely recognized by antisera specific for the CTE of standard hCGβ, especially the carbohydrate-sensitive antiserum R141. The O-linked oligosaccharides of standard hCGβ are heterogeneous in size; 13% are of the largest (hexasaccharide) form. In contrast, over 50% of the O-linked oligosaccharides in hCGβ from the JAr choriocarcinoma cell line are hexasaccharides. Like desialylated ElBre hCGβ, desialylated JAr hCGβ bound completely to peanut agglutinin, but was incompletely recognized by antisera to the hCGβ-CTE. Furthermore, JAr hCGβ was intermediate in size between standard hCGβ and ElBre hCGβ when analysed by gel chromatography (apparent molecular weight 49 000). Thus, we propose that ElBre hCGβ had an even higher proportion of large O-linked oligosaccharides than had JAr hCGβ. Moreover, the N-linked oligosaccharides of ElBre hCGβ differed from standard hCGβ; only 55% of ElBre hCGβ bound to Concanavalin A versus 89% of standard hCGβ. These data further support the concepts of aberrant glycosylation by neoplastic tissues and carbohydrate heterogeneity of hCGβ produced by various tissues. J. Endocr. (1985) 107, 403–408

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