title: Rapid detection of semenogelin by one-step immunochromatographic assay for semen identification.
abstract: To identify semen in forensic samples, we developed an analytical system for one-step immunoassay that has been constructed using the concept of immunochromatography and can identify semenogelin (Sg), which originates in the seminal vesicles. The system employed monoclonal antibody (mAb) and polyclonal antibody (pAb) against recombinant Sg-II (63 kDa), which has been synthesized in insect cells using baculovirus. The two antibodies bound with the seminal plasma motility inhibitor (SPMI; 14 kDa) as a final fragment peptide of Sg. The test stick is based on the sandwich technique using the above antibodies. When serial dilutions of seminal plasma were analyzed using this test stick, the intensity of a clear immunoreactive signal peaked at 2000-fold dilution. Thereafter, the signals decreased slowly but still persisted up to 400,000-fold dilution. The Sg antigen was undetectable in saliva, urine, breast milk, serum or vaginal secretions. Also, the test stick shown did not react with animal semen samples, such as those from horses, dogs, swine and bulls. When semen samples, diluted 100,000-fold from 100 men were tested, the Sg antigenic activity was detectable in all samples. In addition, the specificity and sensitivity of the test stick for identification of semen were demonstrated by comparative forensic studies. We conclude that this immunoassay method is a useful confirmatory test for the identification of semen. The immunochromatographic system for forensic testing or research use will become available commercially soon.
authors.affiliation: Scientific Crime Laboratory, Kanagawa Perfectual Police, Yokohama, Japan. itaru-s@m2.ocv.ne.jp
authors.forename: Itaru
authors.initials: I
authors.lastname: Sato
authors.forename: Koichiro
authors.initials: K
authors.lastname: Kojima
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yamasaki
authors.forename: Kaoru
authors.initials: K
authors.lastname: Yoshida
authors.forename: Miki
authors.initials: M
authors.lastname: Yoshiike
authors.forename: Shoichi
authors.initials: S
authors.lastname: Takano
authors.forename: Toshiji
authors.initials: T
authors.lastname: Mukai
authors.forename: Teruaki
authors.initials: T
authors.lastname: Iwamoto
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D002845:Chromatography; D005260:Female; D005554:Forensic Medicine / Q000379:methods*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D012661:Semen; D029607:Seminal Vesicle Secretory Proteins / Q000032:analysis* / Q000276:immunology; D012680:Sensitivity and Specificity
chemical_list: D000906:Antibodies; D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen