You need JavaScript to view this

Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand

Journal Article:

Abstract

Insulin-like growth factor binding proteins interfere in the IGF-I and -II radioimmunoassays. In an attempt to overcome this problem, we have compared the use of truncated IGF-I, with reduced IGFBP affinity, and IGF-I as radioligands for IGF-I RIA measurements in serum separated by acid gel filtration or acid ethanol extraction followed by cryo-precipitation. With truncated IGF-I as radioligand the IGF-I measurements in acid gel filtrates and acid ethanol extracts were significantly correlated in healthy subjects (N=42, r=0.91, p<0.001) and in patients with acromegaly (N=10, r=0.85, p<0.01), GH deficiency (N=10, r=0.88, p<0.001) or Type I diabetes mellitus (N=10, r=0.90, p<0.001). In contrast, the IGF-I concentrations in acid ethanol extracts determined with IGF-I as radioligand did not correlate with those in acid gel filtrates using truncated IGF-I radioligand in patients with acromegaly (r=0.61, NS) or GH deficiency (r=0.46, NS). In the latter group the mean IGF-I concentrations measured in acid ethanol extracts were erroneously elevated by 112%. Low-affinity antibodies used for IGF-II RIA determinations failed to give reliable results in acid ethanol extracts from patients with Type I diabetes mellitus or GH deficiency. In conclusion, erroneously high IGF-I concentrations owing to binding of the radioligand to IGFBPs not completely removed by acid  More>>
Authors:
Bang, P; Eriksson, U; Wivall, I -L; Hall, K; [1]  Sara, V [2] 
  1. Department of Endocrinology, Karolinska Institute, Stockholm (Sweden)
  2. Department of Pathology, Karolinska Institute, Stockholm (Sweden)
Publication Date:
Jan 01, 1991
Product Type:
Journal Article
Reference Number:
AIX-22-084122; EDB-92-007177
Resource Relation:
Journal Name: Acta Endocrinologica; (Denmark); Journal Volume: 124
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; 38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; GROWTH FACTORS; RADIOIMMUNOASSAY; IMMUNOGLOBULINS; STRUCTURE-ACTIVITY RELATIONSHIPS; INSULIN; ETHANOL; FILTRATION; PATIENTS; PEPTIDE HORMONES; SOLVENT EXTRACTION; ALCOHOLS; BIOASSAY; DIAGNOSTIC TECHNIQUES; EXTRACTION; GLOBULINS; HORMONES; HYDROXY COMPOUNDS; IMMUNOASSAY; IMMUNOLOGY; ISOTOPE APPLICATIONS; MITOGENS; ORGANIC COMPOUNDS; PROTEINS; RADIOASSAY; RADIOIMMUNODETECTION; RADIOIMMUNOLOGY; SEPARATION PROCESSES; TRACER TECHNIQUES; 550601* - Medicine- Unsealed Radionuclides in Diagnostics; 400700 - Radiochemistry & Nuclear Chemistry
OSTI ID:
6202122
Country of Origin:
Denmark
Language:
English
Other Identifying Numbers:
Journal ID: ISSN 0001-5598; CODEN: ACENA
Submitting Site:
DKN
Size:
Pages: 620-629
Announcement Date:

Journal Article:

Citation Formats

Bang, P, Eriksson, U, Wivall, I -L, Hall, K, and Sara, V. Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand. Denmark: N. p., 1991. Web.
Bang, P, Eriksson, U, Wivall, I -L, Hall, K, & Sara, V. Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand. Denmark.
Bang, P, Eriksson, U, Wivall, I -L, Hall, K, and Sara, V. 1991. "Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand." Denmark.
@misc{etde_6202122,
title = {Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand}
author = {Bang, P, Eriksson, U, Wivall, I -L, Hall, K, and Sara, V}
abstractNote = {Insulin-like growth factor binding proteins interfere in the IGF-I and -II radioimmunoassays. In an attempt to overcome this problem, we have compared the use of truncated IGF-I, with reduced IGFBP affinity, and IGF-I as radioligands for IGF-I RIA measurements in serum separated by acid gel filtration or acid ethanol extraction followed by cryo-precipitation. With truncated IGF-I as radioligand the IGF-I measurements in acid gel filtrates and acid ethanol extracts were significantly correlated in healthy subjects (N=42, r=0.91, p<0.001) and in patients with acromegaly (N=10, r=0.85, p<0.01), GH deficiency (N=10, r=0.88, p<0.001) or Type I diabetes mellitus (N=10, r=0.90, p<0.001). In contrast, the IGF-I concentrations in acid ethanol extracts determined with IGF-I as radioligand did not correlate with those in acid gel filtrates using truncated IGF-I radioligand in patients with acromegaly (r=0.61, NS) or GH deficiency (r=0.46, NS). In the latter group the mean IGF-I concentrations measured in acid ethanol extracts were erroneously elevated by 112%. Low-affinity antibodies used for IGF-II RIA determinations failed to give reliable results in acid ethanol extracts from patients with Type I diabetes mellitus or GH deficiency. In conclusion, erroneously high IGF-I concentrations owing to binding of the radioligand to IGFBPs not completely removed by acid ethanol extraction can be avoided by the use of truncated IGF-I as radioligand. (author).}
journal = {Acta Endocrinologica; (Denmark)}
volume = {124}
journal type = {AC}
place = {Denmark}
year = {1991}
month = {Jan}
}