title: Relaxin-like factor: a highly specific and constitutive new marker for Leydig cells in the human testis.
abstract: The complete protein-coding region of the human relaxin-like factor (RLF; formerly Ley-I-L) was cloned by reverse transcription-polymerase chain reaction from human testis and subcloned into a bacterial expression plasmid for the production of recombinant human RLF in Escherichia coli. Polyclonal antibodies were raised against the recombinant RLF, as well as against a peptide epitope from the B-domain of the RLF polypeptide. Antibodies were used for immunohistochemistry of Bouin-fixed, paraffin-embedded samples of human testis tissues. Specific immunoreactivity was located exclusively in the Leydig cells with a consistent high intensity of staining, showing similar spatial distribution to other Leydig cell markers, such as the luteinizing hormone (LH) receptor and 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), and to the pattern of RLF mRNA shown by in-situ transcript hybridization. In biopsy samples from patients with severe disturbances of spermatogenesis, RLF staining intensity was consistently high in all cases, unlike staining for 3 beta-HSD which varied considerably between patients. Immunostaining for RLF would thus appear to offer an interesting new marker for Leydig cells in human testis samples.
authors.affiliation: Institute for Hormone and Fertility Research, University of Hamburg, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Ivell
authors.forename: M
authors.initials: M
authors.lastname: Balvers
authors.forename: R
authors.initials: R
authors.lastname: Domagalski
authors.forename: H
authors.initials: H
authors.lastname: Ungefroren
authors.forename: N
authors.initials: N
authors.lastname: Hunt
authors.forename: W
authors.initials: W
authors.lastname: Schulze
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D000328:Adult; D001483:Base Sequence; D015415:Biomarkers; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007248:Infertility, Male / Q000378:metabolism / Q000473:pathology; D007328:Insulin; D007985:Leydig Cells / Q000378:metabolism*; D008297:Male; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011974:Receptors, LH / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D013737:Testis / Q000166:cytology* / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D017931:DNA Primers; D007328:Insulin; C084797:Leydig insulin-like protein; D011506:Proteins; D012333:RNA, Messenger; D011974:Receptors, LH; D011994:Recombinant Proteins; D015096:3-Hydroxysteroid Dehydrogenases