TY - JOUR
T1 - Specificity and sensitivity of commercially available assays for glucagon and oxyntomodulin measurement in humans
AU - Bak, Monika Judyta
AU - Wewer Albrechtsen, Nicolai Jacob
AU - Pedersen, Jens
AU - Hartmann, Bolette
AU - Christensen, Mikkel
AU - Vilsbøll, Tina
AU - Knop, Filip Krag
AU - Deacon, Carolyn F
AU - Dragsted, Lars Ove
AU - Holst, Jens Juul
N1 - CURIS 2014 NEXS 021
PY - 2014/4
Y1 - 2014/4
N2 - Aim: To determine the specificity and sensitivity of assays carried out using commercially available kits for glucagon and/or oxyntomodulin measurements. Methods: Ten different assay kits used for the measurement of either glucagon or oxyntomodulin concentrations were obtained. Solutions of synthetic glucagon (proglucagon (PG) residues 33-61), oxyntomodulin (PG residues 33-69) and glicentin (PG residues 1-69) were prepared and peptide concentrations were verified by quantitative amino acid analysis and a processing-independent in-house RIA. Peptides were added to the matrix (assay buffer) supplied with the kits (concentration range: 1.25-300 pmol/l) and to human plasma and recoveries were determined. Assays yielding meaningful results were analysed for precision and sensitivity by repeated analysis and ability to discriminate low concentrations. Results and conclusion: Three assays were specific for glucagon (carried out using the Millipore (Billerica, MA, USA), Bio-Rad (Sundbyberg, Sweden), and ALPCO (Salem, NH, USA) and Yanaihara Institute (Shizuoka, Japan) kits), but none was specific for oxyntomodulin. The assay carried out using the Phoenix (Burlingame, CA, USA) glucagon kit measured the concentrations of all three peptides (total glucagon) equally. Sensitivity and precision were generally poor; the assay carried out using the Millipore RIA kit performed best with a sensitivity around 10 pmol/l. Assays carried out using the BlueGene (Shanghai, China), USCN LIFE (Wuhan, China) (oxyntomodulin andglucagon),MyBioSource (San Diego, CA, USA)and Phoenix oxyntomodulin kits yielded inconsistent results.
AB - Aim: To determine the specificity and sensitivity of assays carried out using commercially available kits for glucagon and/or oxyntomodulin measurements. Methods: Ten different assay kits used for the measurement of either glucagon or oxyntomodulin concentrations were obtained. Solutions of synthetic glucagon (proglucagon (PG) residues 33-61), oxyntomodulin (PG residues 33-69) and glicentin (PG residues 1-69) were prepared and peptide concentrations were verified by quantitative amino acid analysis and a processing-independent in-house RIA. Peptides were added to the matrix (assay buffer) supplied with the kits (concentration range: 1.25-300 pmol/l) and to human plasma and recoveries were determined. Assays yielding meaningful results were analysed for precision and sensitivity by repeated analysis and ability to discriminate low concentrations. Results and conclusion: Three assays were specific for glucagon (carried out using the Millipore (Billerica, MA, USA), Bio-Rad (Sundbyberg, Sweden), and ALPCO (Salem, NH, USA) and Yanaihara Institute (Shizuoka, Japan) kits), but none was specific for oxyntomodulin. The assay carried out using the Phoenix (Burlingame, CA, USA) glucagon kit measured the concentrations of all three peptides (total glucagon) equally. Sensitivity and precision were generally poor; the assay carried out using the Millipore RIA kit performed best with a sensitivity around 10 pmol/l. Assays carried out using the BlueGene (Shanghai, China), USCN LIFE (Wuhan, China) (oxyntomodulin andglucagon),MyBioSource (San Diego, CA, USA)and Phoenix oxyntomodulin kits yielded inconsistent results.
U2 - 10.1530/eje-13-0941
DO - 10.1530/eje-13-0941
M3 - Journal article
C2 - 24412928
SN - 0804-4643
VL - 170
SP - 529
EP - 538
JO - European Journal of Endocrinology
JF - European Journal of Endocrinology
IS - 4
ER -