Placental-type alkaline phosphatase in human seminal plasma from fertile and infertile men

Germ Cell Alkaline Phosphatase in Human Seminal Plasma following Vasectomy

“…The remaining patient did not have detectable preoperative seminal plasma GCAP in the H17-E2based GCAP immunoassay. This is consistent with previous data for occasional patients (McLaughlin et a/., 1986) and may be due to non-reactivity of this mAb with certain phenotypes of GCAP, as has previously been described for PLAP (McLaughlin et af., 1983). These findings are consistent with the majority of this GCAP being produced within the testis, and earlier immunohistochemical studies have demonstrated the expression of GCAP by intratubular cells in the testis which are thought to be of germ cell origin (Paiva et a/., 1983).…”

“…Germ cell alkaline phosphatase (GCAP) is found in normal testicular tissue together with trace amounts of placental alkaline phosphatase (PLAP) (McLaughlin et al, 1984). Human ejaculates are known to have alkaline phosphatase activity (Mann and Lutwak-Mann, 1951) and our previous work has quantitated the presence of seminal plasma GCAP in fertile and infertile males (McLaughlin et al, 1986). In cases of azoospermia, due to either an obstructive aetiology or germinal failure, seminal plasma GCAP levels were very low.…”

“…Estimations of PLAP and GCAP were performed by solid-phase enzyme immunoassays based on the murine IgG1 mAbs H317 and H17-E2, together with simultaneous L-leucine sensitivity estimations (McLaughlin et a/., 1983(McLaughlin et a/., , 1984(McLaughlin et a/., , 1986. The H17-E2 mAb reacts with both PLAP and GCAP and the H317 reacts with PLAP alone; neither reacts with other forms of alkaline phosphatase (McLaughlin et a/., 1983 ;Travers and Bodmer, 1984).…”

“…The H17-E2 mAb reacts with both PLAP and GCAP and the H317 reacts with PLAP alone; neither reacts with other forms of alkaline phosphatase (McLaughlin et a/., 1983 ;Travers and Bodmer, 1984). The assay has been previously described in detail (McLaughlin et a/., 1983(McLaughlin et a/., , 1984(McLaughlin et a/., , 1986, but briefly the mAb was immobilised on to micro-ELISA plate wells (Dynatech) through rabbit antimouse immunoglobulin (Dakopatts) and then incubated with the seminal plasma sample diluted 2fold in phosphate-buffered isotonic saline, pH 7.4. Any PLAP or GCAP subsequently bound was estimated by colour change in a phosphatase substrate.…”

Alkaline Phosphatase in Human Semen: An Investigation Using Enzyme Inhibitors and Gel Electrophoresis

“…In order to use alkaline phosphatase isoenzymes as markers for studying the function of their secretory organs, it will apparently be necessary to utilize assays, such as the ELISA method of McLaughlin (18), based upon the use of a monoclonal antibody specific to the one isoenzyme which is to be measured.…”