We have characterized the folate receptor in normal and malignant tissue from male gonads. Radioligand binding displayed characteristics typical of other folate receptors. Those included a high-affinity type of binding (K = 1010 M−1), apparent positive cooperativity changing into non-cooperativity at low receptor concentrations, a tendency to increased binding affinity with decreasing receptor concentrations, a slow dissociation at pH 7.4 becoming rapid at pH 3.5 and inhibition by folates, in particular oxidized forms. The gel filtration profile of Triton X-100 solubilized tissue contained a 25 and 100 kDa peak of radioligand-receptor. The latter peak could represent receptor equipped with a hydrophobic membrane anchor that inserts into Triton X-100 micelles. The concentration of radiolabelled receptor ranged from 0.41 nmol/g protein to 1.68 nmol/g protein in specimens of normal testicular tissue from patients with prostatic carcinomas and from 1.54 nmol/g protein to 3.82 nmol/g protein in testicular tissue from young individuals. Compared to normal testicular tissue the concentration of receptor in seminoma tissue was low (0.38–1.27 nmol/g protein) but showed a higher degree of immunoreactivity in the presence of antibodies against human milk folate binding protein as evidenced by ELISA and immunohistochemistry data. Hence a folate receptor isoform homologous to human milk folate binding protein is apparently expressed in seminomas where the total expression of receptor, however, seems to be lower than in normal testicles.
Skip Nav Destination
Article navigation
Research Article|
December 01 1999
Characterization of a High-Affinity Folate Receptor in Normal and Malignant Human Testicular Tissue
Jan Holm;
Jan Holm
1Department of Clinical Chemistry, Central Hospital Herning, Herning, DK-7400 Denmark
Search for other works by this author on:
Steen Ingemann Hansen;
Steen Ingemann Hansen
2Department of Clinical Chemistry, Central Hospital, Hillerød, DK-, 3400, Denmark
Search for other works by this author on:
Mimi Høier-Madsen;
Mimi Høier-Madsen
3Laboratory for Autoimmune Serology, State Serum Institute, Copenhagen, DK 2300 S, Denmark
Search for other works by this author on:
Thomas Broe Christensen;
Thomas Broe Christensen
4Department of Oncology, Århus Kommunehospital Århus, DK-8000, Denmark
Search for other works by this author on:
Carl W. Nichols
Carl W. Nichols
5Department of Pathology, West Paces Medical Center, 3200 Howell Mill Rd. NW, Atlanta, GA 30327, U.S.A.
Search for other works by this author on:
Publisher: Portland Press Ltd
Online ISSN: 1573-4935
Print ISSN: 0144-8463
© 1999 Plenum Publishing Corporation
1999
Biosci Rep (1999) 19 (6): 571–580.
Citation
Jan Holm, Steen Ingemann Hansen, Mimi Høier-Madsen, Thomas Broe Christensen, Carl W. Nichols; Characterization of a High-Affinity Folate Receptor in Normal and Malignant Human Testicular Tissue. Biosci Rep 1 December 1999; 19 (6): 571–580. doi: https://doi.org/10.1023/A:1020219029206
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Biochemical Society Member Sign in
Sign InSign in via your Institution
Sign in via your InstitutionGet Access To This Article
Open Access for all
We offer compliant routes for all authors from 2025. With library support, there will be no author nor reader charges in 5 journals. Check here |
![]() |