title: Differential leucocyte detection by flow cytometry improves the diagnosis of genital tract inflammation and identifies macrophages as proinflammatory cytokine-producing cells in human semen.
abstract: Genital tract inflammation is considered as a major cause of male infertility with leucocytospermia as widely used diagnostic marker. However, threshold of 10(6) leucocytes ml(-1) recommended by the WHO is a matter of debate. Moreover, leucocyte subpopulations and their impact cannot be identified by the routine peroxidase method (POM). Ejaculates of subfertile men (n = 47) were analysed by flow cytometry (FACS) using a bead-based method. Leucocytes were identified by CD18 and further divided into macrophages (HLA-Dr+/CD66abce-) and neutrophils (HLA-Dr-/CD66abce+). IL-1β, TNF-α and IL-6 production was investigated in these subpopulations. It was found that CD18-positive cells correlated significantly with POM. However, only in samples with POM below 10(6) per millilitre, FACS detected significantly higher leucocyte numbers. Moreover, in 31% of these samples, FACS leucocyte detection reached threshold values greater than 1 × 10(6)  ml(-1) , fulfilling the criteria for diagnosis of leucocytospermia. Neutrophils were the predominating leucocyte population. Nevertheless, in 24% of samples, macrophages encountered more than 50% of leucocytes. Most interestingly, only macrophages produced significant amounts of IL-1β, TNF-α and IL-6. It is concluded that FACS improves detection and functional differentiation of seminal leucocytes as one of the diagnostic hallmarks of male genital tract inflammation.
authors.affiliation: Department of Dermatology and Allergy/Andrology Unit, Rheinische Friedrich-Wilhelms University, Bonn, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Fathy
authors.forename: S J
authors.initials: SJ
authors.lastname: Chen
authors.forename: N
authors.initials: N
authors.lastname: Novak
authors.forename: H-C
authors.initials: HC
authors.lastname: Schuppe
authors.forename: G
authors.initials: G
authors.lastname: Haidl
authors.forename: J-P
authors.initials: JP
authors.lastname: Allam
mesh_terms: D000328:Adult; D016207:Cytokines / Q000096:biosynthesis; D005434:Flow Cytometry / Q000379:methods; D005832:Genital Diseases, Male / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D006801:Humans; D007249:Inflammation / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D018836:Inflammation Mediators / Q000378:metabolism; D053583:Interleukin-1beta / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D007958:Leukocyte Count; D007962:Leukocytes / Q000145:classification / Q000276:immunology / Q000473:pathology*; D008264:Macrophages / Q000276:immunology / Q000473:pathology; D008297:Male; D009504:Neutrophils / Q000276:immunology / Q000473:pathology; D012661:Semen / Q000166:cytology* / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D016207:Cytokines; C508600:IL6 protein, human; D018836:Inflammation Mediators; D053583:Interleukin-1beta; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha
keywords: Flow cytometry; infertility; inflammation; leucocytes; semen