Interference in a radioimmunoassay for human thyrotropin. [/sup 125/I tracer technique]

Journal Article · Tue Mar 01 00:00:00 EST 1977 · Clin. Chem.; (United States)

OSTI ID:7219803

Spencer, C A ^[1]; Challand, G S

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1. Glasgow Royal Infirmary

Abnormally high plasma thyrotropin values were found by radioimmunoassay in some patients when an antiserum to porcine thyrotropin was used, normal results being obtained with an antiserum raised to human thyrotropin. These discrepancies were found in some subjects with no biochemical or clinical evidence of hypothyroidism and occasionally in sera from patients with unequivocal hyperthyroidism. We found a substance in serum that cross reacts with the anti-porcine antiserum, is stable on repeated freezing and thawing, and is independent of the /sup 125/I-labeled tracer preparation. It is unlikely that this substance is a separation-stage artefact related to immunoglobulins. Its apparent molecular weight (gel filtration) is 114,000, as compared with apparent molecular weights for standard thyrotropin and endogenous thyrotropin (as found in idiopathic hypothyroidism) of 34,700 and 38,000, respectively. We believe the substance is a normal serum constituent that is present in large quantities in a minority of subjects. Apparently unrelated to TSH, its exact chemical nature remains unidentified.

• OSTI ID: 7219803
• Journal Information: Clin. Chem.; (United States), Vol. 23:3
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
TSH
RADIOIMMUNOASSAY
BLOOD PLASMA
HYPERTHYROIDISM
HYPOTHYROIDISM
IMMUNE SERUMS
IMMUNOGLOBULINS
IODINE 125
PATIENTS
TRACER TECHNIQUES
BETA DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
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DAYS LIVING RADIOISOTOPES
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
ENDOCRINE DISEASES
GLOBULINS
HORMONES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PEPTIDE HORMONES
PITUITARY HORMONES
PROTEINS
RADIOASSAY
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550601* - Medicine- Unsealed Radionuclides in Diagnostics