Abstract
Neonatal mass-screening for the diagnosis of 21-hydroxylase deficiency has been carried out by measuring 17-hydroxyprogesterone (17-0H-P). It is well recognized that results of the direct measurement of 17-OH-P are much higher than the corresponding results following solvent extraction, and this discrepancy is most marked in premature babies. It is considered that the cause of this discrepancy is because of existance of cross-reactive substance (s) with antibody in serum of premature babies. To investigate the cross-reactive substance (s), serum from premature baby was extracted and applied to high-performance liquid chromatography (HPLC). Eluates were collected and assayed by 17-OH-P enzyme immunoassay (EIA) to investigate fraction (s) which was reacted with the antibody used in the EIA. The results revealed that 17- hydroxypregnenolone, 17-hydroxypregnenolone 3-sulfate and pregnenolone 3-sulfate were crossreactive substances in the EIA. In the above experiment, an unknown cross-reactive fraction was observed. To investigate this substance, the fraction was applied to GC/MS analysis. As a result, 16-dehydropregnenolone 3-sulfate was identified by the GC/MS analysis. To our knowledge, this is the first report to identify 16- dehydropregnenolone 3-sulfate in human serum.
In conclusion, cross-reactive substances in our EIA were 17-hydroxypregnenolone, 17-hydroxypregnenolone 3-sulfate, pregnenolone 3-sulfate and 16-pregnenolone 3-sulfate.
