Quantitation of plasma levels of tetranectin--effects of oral contraceptives, pregnancy, treatment with L-asparaginase and liver cirrhosis.
Tetranectin is a tetrameric protein that binds to kringle 4 of plasminogen. Increase of electrophoretic mobility of the otherwise slowly migrating tetranectin in the presence of ethylenediaminetetraacetate was used to develop a reproducible electroimmunoassay to quantify plasma levels. Plasma levels in normals were found within narrow limits of 100 +/- 16 (SD)%, (100% = 0.15 mumol/l). There was no difference between males and females, smokers and non-smokers, and there were no significant changes with age from 20 to 49 years. Patients with severe liver cirrhosis showed a large variation in plasma tetranectin levels but no systematic or average reduction, in contrast to strong reductions in plasma levels of other proteins. Patients treated with L-asparaginase showed a gradual reduction in time in plasma levels of various proteins, though tetranectin showed no significant reduction. It is concluded that tetranectin can be assayed reproducibly in plasma and has a well regulated plasma level. This level is not sensitive to conditions with reductions in synthesis of many proteins, such as during cirrhosis of the liver and during L-asparaginase therapy. The reductions in plasma levels during the use of oral contraceptives and pregnancy indicate involvement of sex steroids in the metabolism of tetranectin.
Kluft
C
C
Gaubius Institute TNO, Leiden, The Netherlands.
Los
P
P
Clemmensen
I
I
Brommer
E J
EJ
Gevers Leuven
J A
JA
Boks
A L
AL
Vellenga
E
E
D000293:Adolescent; D000328:Adult; D001215:Asparaginase / Q000494:pharmacology*; D001798:Blood Proteins / Q000378:metabolism*; D003276:Contraceptives, Oral / Q000494:pharmacology*; D005260:Female; D006801:Humans; D037181:Lectins, C-Type; D008103:Liver Cirrhosis / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011247:Pregnancy / Q000097:blood*; D012016:Reference Values
D001798:Blood Proteins; D003276:Contraceptives, Oral; D037181:Lectins, C-Type; C048648:tetranectin; D001215:Asparaginase