[A new method for the determination of serum human placental lactogen (HPL) by single radial immunodiffusion (author's transl)].
The general radioimmunoassay (RIA) currently employed for the determination of serum HPL requires a special apparatus and a complicated technique. Therefore, in order to simplify the assay we tried to develop a new method using single radial immunodiffusion (SRID). Basic examinations were made to establish a simplified HPL assay method by SRID. The optimal conditions finally decided for SRID were as follows: the thickness of the agar plate, 1.5 mm; the diameter of the well, 3 mm; the amount of antigen added, 10 microliter; antibody concentration, 1.0% for the measurement range from 1.0 microgram/ml to 16 microgram/ml and 0.5% for the measurement range from 0.25 microgram/ml to 1.0 microgram/ml. Under these conditions serum HPL was detectable after the 9th week of gestation, and antigen was measurable over 0.25 microgram/ml. Serum HPL values measured by RIA and SRID from the 9th to the 42nd week of gestation in 138 normal pregnant women were identical, and the correlation was highly significant (r = 0.842, p less than 0.001). This SRID method was as reliable and sensitive as the RIA and made it easier than the RIA to measure the serum HPL of pregnant women. Therefore, with regard to placental function its clinical application should prove to be certainly beneficial.
D005260:Female; D006801:Humans; D005779:Immunodiffusion / Q000379:methods*; D010928:Placental Lactogen / Q000097:blood*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third
D010928:Placental Lactogen