A monoclonal antibody-based immunoradiometric assay for low molecular weight insulin-like growth factor binding protein/placental protein 12.
We describe a sensitive immunoradiometric assay for insulin-like growth factor binding protein/Placental Protein12 (IGF-BP/PP12) using monoclonal antibodies. This assay has a detection limit of 0.25 micrograms/l IGF-BP/PP12. Parallel dose response curves were obtained with purified IGF-BP/PP12, amniotic fluid, decidual cytosol extract, and serum. The assay is reproducible (intra-assay variation 4.3-8.2% and interassay variation 9.7-11.1%) and fast (less than 5 hours). A crossreactivity of less than 0.01% for all other proteins tested reflects high specificity. Using this method the mean serum IGF-BP/PP12 concentration in healthy women was 5.2 micrograms/l. During pregnancy, the mean IGF-BP/PP12 at 7-11 weeks was 43.3 micrograms/l, and at 36-40 weeks 121 micrograms/l. After early pregnancy termination the serum IGF-BP/PP12 decreased rapidly reaching a mean level of 8 micrograms/l within 4 days.
Pekonen
F
F
Minerva Institute for Medical Research, Kauniainen, Finland.
Kärkkäinen
T
T
Tanner
P
P
Weber
T
T
Rutanen
E M
EM
D000653:Amniotic Fluid / Q000032:analysis; D000911:Antibodies, Monoclonal; D002352:Carrier Proteins / Q000032:analysis* / Q000097:blood; D003656:Decidua / Q000032:analysis; D005260:Female; D006801:Humans; D015592:Immunoradiometric Assay / Q000379:methods*; D018970:Insulin-Like Growth Factor Binding Protein 1; D018969:Insulin-Like Growth Factor Binding Proteins; D008970:Molecular Weight; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000032:analysis* / Q000097:blood; D013002:Somatomedins / Q000032:analysis
D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; C032231:IGFBP1 protein, human; D018970:Insulin-Like Growth Factor Binding Protein 1; D018969:Insulin-Like Growth Factor Binding Proteins; D011257:Pregnancy Proteins; D013002:Somatomedins