Development and Characterization of Antibodies to a Nicked and Hyperglycosylated Form of hCG from a Choriocarcinoma Patient: Generation of Antibodies That Differentiate Between Pregnancy hCG and Choriocarcinoma hCG
- 1 January 1999
- journal article
- Published by Springer Nature in Endocrine
- Vol. 10 (2), 137-144
- https://doi.org/10.1385/endo:10:2:137
Abstract
Human chorionic gonadotropin (hCG) exists in blood and urine as a variety of isoforms one of which contains peptide bond cleavages within its beta-subunit loop 2 and is referred to as nicked hCG (hCGn). This hCG isoform appears to be more prevalent in the urine of patients with certain malignancies and possibly in some disorders of pregnancy. Until now, only indirect immunoassays could be used to quantify hCGn. We report the development of two monoclonal antibodies (MAbs) to a form of hCGn isolated from a choriocarcinoma patient. This hCG isoform was not only 100% nicked, but also contained 100% tetrasaccharide-core O-linked carbohydrate moieties in its beta COOH-terminal region. Two-site immunometric assays have been developed using these new antibodies, B151 and B152. The former exhibits good specificity for hCGn independent of the source of the hCGn, the form excreted by choriocarcinoma patients or the form of hCGn from normal pregnancies. The latter antibody, B152, is sensitive to the carbohydrate moieties and possibly other differences in hCG isoforms, but is not for nicking of the beta-subunit. These two immunometric assays provide potential novel diagnostic tools for direct measurement of hCG isoforms which could not be accurately quantified earlier before development of the assays using these newly generated antibodies.Keywords
This publication has 30 references indexed in Scilit:
- Differential urinary gonadotrophin profiles in early pregnancy and early pregnancy lossPrenatal Diagnosis, 1998
- Carbohydrate and peptide structure of the α- and β-subunits of human chorionic gonadotropin from normal and aberrant pregnancy and choriocarcinomaEndocrine, 1997
- Biochemical markers of trisomy 21 in amniotic fluid.1997
- AGE-INDEPENDENT INDICES IN SECOND-TRIMESTER SERUM SCREENING FOR DOWN'S SYNDROME ARE USELESSPrenatal Diagnosis, 1996
- Human chorionic gonadotropin beta-subunit nicking enzymes in pregnancy and cancer patient serum.Journal of Clinical Endocrinology & Metabolism, 1994
- The deactivation of hCG by nicking and dissociation.Journal of Clinical Endocrinology & Metabolism, 1993
- The Heterogeneity of Human Chorionic Gonadotropin (hCG). III. The Occurrence and Biological and Immunological Activities of Nicked hCG*Endocrinology, 1991
- The Heterogeneity of Human Chorionic Gonadotropin (hCG). II. Characteristics and Origins of Nicks in hCG Reference Standards*Endocrinology, 1991
- Occurrence of Fragmentation of Free and Combined Forms of the β-Subunit of Human Chorionic Gonadotropin*Endocrinology, 1990
- Preparation and Characterization of Antibodies to the Urinary Fragment of the Human Chorionic Gonadotropin β-Subunit*Endocrinology, 1988