Seminal parameters of chronic male genital inflammation are associated with disturbed sperm DNA integrity.

Definition of chronic male genital tract inflammation and its impact on male infertility is still a matter of debate. In particular, DNA integrity has been reported to be disturbed in subfertile men. Thus, the aim of this study was to investigate an association of DNA integrity to altered standard semen parameters as well as inflammatory parameters such as peroxidase-positive cells, macrophages and seminal interleukin-6 concentration. Macrophages were detected by CD18/HLA-Dr staining, and DNA integrity was analysed by acridine orange staining using flow cytometry. Interleukin-6 was detected by ELISA. Normal DNA integrity showed a significant correlation to sperm number and progressive motility. Moreover, a significant inverse correlation of DNA integrity to Interleukin-6 and macrophages could be demonstrated. Further on, seminal interleukin-6 also significantly correlated to macrophages. No association has been observed between the number of peroxidase-positive cells and normal DNA integrity. As disturbed DNA integrity has been reported to negatively influence spermatozoon-egg interaction and even fertilisation rates following ICSI, and as early miscarriages have been associated with sperm DNA damage, it should be screened very carefully for male genital tract inflammations in couples undergoing infertility treatment. Measuring Interleukin-6 seems superior to assessment of the number of leucocytes alone and additional assessment of DNA integrity into the diagnostic work-up should be considered.

Mast cells in the seminal plasma of infertile men as detected by flow cytometry.

Increased numbers of mast cells (MCs) in the testis have been associated with testicular dysfunction, where accumulation of MCs occurs. Furthermore, it has been reported that MCs might affect sperm function as it has been demonstrated that MC-derived tryptase in the seminal fluid might reduce sperm motility. Although MCs have been detected in rat epididymis, only little is known about the presence of MCs in human seminal plasma. Thus, we analysed MC numbers in the ejaculate of men during routine semen analysis of male patients suspected for infertility (n = 100). MCs were detected by c-kit (CD117) expression using flow cytometry. Thereby, we detected significant numbers of MCs in the ejaculate of most patients (559 +/- 525 MCs ml(-1), mean +/- SD). However, we could neither detect a correlation with respect to MCs and sperm count, motility or morphology nor to the seminal inflammatory markers like polymorphonuclear elastase. Nevertheless, a significant correlation of MCs to spermatozoa-bound IgA (r = 0.5; P = 0.03; n = 21) was observed. It is concluded that significant numbers of MCs can be detected in the human ejaculate without necessarily influencing sperm function. A potential role of MCs in seminal plasma as well as the association between MCs and IgA on spermatozoa remains to be elucidated.

High percentage of apoptotic spermatozoa in ejaculates from men with chronic genital tract inflammation.

Silent chronic inflammation of genital tract (CIGT) is considered as a major contributing factor to male fertility disorders. Within CIGT, inflammatory cytokines such as TNF-alpha might induce spermatozoal apoptosis, which in turn has been shown to have a negative influence on the sperm-oocyte penetration capacity. Thus, the aim of this study was to investigate spermatozoal apoptosis in patients with fertility disorders and signs of CIGT. Apoptosis of spermatozoa was determined by expression of annexin V using flow cytometry. Apoptotic spermatozoa were further discriminated from necrotic spermatozoa by 7-amino-actinomycin (7AAD). Ejaculates of patients showing signs of CIGT (P-CIGT) such as high polymorphonuclear (PMN) elastase were compared to control ejaculates of patients lacking signs of CIGT (CON). Thereby we detected a significant correlation between PMN elastase and TNF-alpha in the seminal plasma and apoptotic spermatozoa. Furthermore, we demonstrated a significantly higher percentage of apoptotic spermatozoa in the ejaculate of P-CIGT compared to CON. Interestingly, a significantly higher percentage of apoptotic spermatozoa was detected in the swim-up fraction demonstrating motility of apoptotic spermatozoa. This is in line with the missing correlation of apoptotic spermatozoa and motility. In conclusion, patients with signs of CIGT display high numbers of apoptotic spermatozoa with progressive motility, which might have an impact on reproductive techniques such as intrauterine insemination or in-vitro fertilisation.

CD7-negative helper T cells accumulate in inflammatory skin lesions.

Recently, we identified a particular T-cell subset in the peripheral blood of normal individuals that lack CD7 expression. In this study we determined the portion of CD7- T cells in the peripheral blood and skin of patients with various inflammatory skin diseases. We found that skin-infiltrating lymphocytes isolated from different benign and malignant skin lesions (n = 20) contain a high portion of CD7- helper T cells, whereas the number of CD7- T cells in the peripheral blood was not altered compared to healthy controls. Cell activation in vitro did not induce CD7 expression in negative T cells but increased CD7 expression in CD7-positive cells. Thus, lack of CD7 expression seems to be a stable characteristic in a major subset of skin-infiltrating lymphocytes. During long-term culture of CD7- helper T-cell clones derived from a psoriasis skin lesion, no phenotypic change in the CD7 phenotype could be monitored by sequential flow-cytometric analyses. No CD7 mRNA could be detected by Northern blot analysis, indicating transcriptional regulation of CD7 expression. The results show that CD7- T cells accumulate in certain inflammatory skin lesions without alteration of the circulating CD7- population. These cells may be identical to or derived from CD7- T cells of the peripheral blood.

Progressive increase of CD7- T cells in human blood lymphocytes with ageing.

CD7 is one of the major surface antigens expressed very early during T cell ontogeny. Lack of CD7 expression on mature T cells is regarded as a classical feature of malignant T cells in certain forms of cutaneous T cell lymphoma. Previously, we identified a CD7- subset of peripheral blood T lymphocytes in normal human individuals. In this study we determined the portion of CD7- T cells in the peripheral blood of healthy volunteers ranging in age from 8 months to 90 years (n = 85) and in cord blood of full-term infants (n = 14). Furthermore, this CD7- subset was characterized in detail by the use of MoAbs and three-colour flow cytometry. In cord blood no CD7- T cells could be detected. After birth, percentage and absolute number of CD7- T cells increased with age. Independently of age, most CD7-CD3+ cells belonged to the CD4+ subpopulation. Focusing on the latter we could demonstrate the predominance of the CD45RO+CD45RA- phenotype in the CD7- subset. Furthermore, CD7- T cells contained a higher number of cells expressing activation markers and the CD57 antigen, but a reduced number of CD62L+ cells in comparison with CD7+ T cells.

Induction of nuclear contour irregularity during T-cell activation via the T-cell receptor/CD3 complex and CD2 antigens in the presence of phorbol esters.

To determine whether specific T-cell activation pathways could produce nuclear contour irregularity in normal human lymphocytes, purified T cells were stimulated in vitro and subsequently analyzed by electron microscopy. The degree of nuclear contour irregularity was determined with the use of a computerized planimeter. Stimulation via the T-cell receptor (TCR)/CD3 complex using anti-CD3 monoclonal antibodies induced Sézary-like morphology (nuclear contour indices > 6.5) in a significant portion (9% to 28%) of T cells derived from different normal donors. T-cell activation via CD2 antigens showed induction of Sézary-like nuclear morphology in a lower percentage of cells in comparison with stimulation via the TCR/CD3 complex. In contrast, mitogenic stimulation in vitro did not induce alterations of nuclear morphology in T cells. Immunoelectron microscopy showed that nuclear contour irregularity induced in vitro did not correlate with surface-antigen expression of T-cell subpopulations. The results indicate that Sézary-like morphology is associated with cell activation in normal human T cells.

CD7- T cells represent a subset of normal human blood lymphocytes.

In the peripheral blood of normal adults we identified a subpopulation of mature human T cells that lacks expression of CD7. These CD3+CD7- T cells represent 9% +/- 3.4 SD of PBMC as estimated by analyses of 38 different normal donors. The majority of CD7- T cells express TCR alpha/beta, and are of CD4 helper and CD45RO+CD45RA- "memory" phenotype as determined by three-color fluorescence analysis. We established seven CD4+CD7- T cell clones in vitro from purified CD7- blood T cells and compared these cells to CD4+CD7+ clones. Nonexpression and expression, respectively, of CD7 was a stable feature of all clones during long term culture for more than 6 mo. No CD7 mRNA could be detected by dot blot and Northern blot analysis of purified CD7- T cells and of expanded T cell clones implicating a transcriptional regulation of CD7 Ag expression. Ionomycin/TPA and PHA stimulation were not capable to induce CD7 expression in CD7- cells but up-regulated CD7 expression in CD7+ cells. Whereas CD7- cells of cutaneous T cell lymphoma exhibit a cerebriform nucleus (Sézary cells), no evidence was obtained for cerebriform nuclear morphology in normal CD7- T cells from peripheral blood. We suggest that these CD7- T cells represent a physiologic subset of mature T cells and may be the circulating counterpart of those lymphocytes that are found to be enriched in normal skin and in a variety of benign and malignant skin diseases.