White blood cells in semen affect hyperactivation but not sperm membrane integrity in the head and tail regions

Relationship between leukocytospermia, reproductive potential after assisted reproductive technology, and sperm parameters: a systematic review and meta-analysis of case-control studies

BACKGROUND

The association of leukocytospermia with male fertility is still under debate.

OBJECTIVE

To evaluate the impact of leukocytospermia (≥1 × 10⁶  white blood cells/mL of semen, according to the World Health Organization) in men attending a fertility clinic for couple subfertility, on fertility outcomes after assisted reproductive technology (ART) and on semen quality.

MATERIALS AND METHODS

A systematic review with meta-analysis of case-control studies reporting mean ± standard deviation for values of different seminal parameters (sperm concentration, progressive motility, sperm morphology, sperm DNA fragmentation, semen volume, and Ph) and fertilization rate (FR), or the odds ratio (OR) for clinical pregnancy rate (PR) per cycle after ART in leukocytospermic and non-leukocytospermic patients was performed. A literature search was carried out in MEDLINE and SCOPUS for English-language studies published till June 2018.

RESULTS

Twenty-eight case-controlled retrospective studies met the inclusion criteria, comparing fertility outcomes after ART or semen parameters in men with or without leukocytospermia. FR and PR after ART were not significantly different in the two groups. Leukocytospermic samples showed a lower sperm concentration (pooled SMD = -0.14; 95% CI: -0.28, -0.01, I²  = 71%, p_{for heterogeneity}  < 0.00001) and a lower progressive motility (pooled SMD = -0.18; 95% CI: -0.29, -0.06; I²  = 59%, p_{for heterogeneity}  < 0.0001). However, the significant differences disappeared, along with the large inter-study heterogeneity, when analyses were restricted to studies clearly reporting the inclusion of men without clinical evidence of seminal tract infection.

DISCUSSION AND CONCLUSION

Leukocytospermia in men seeking consultation for couple subfertility is not associated with a reduced fertility after ART and with altered semen quality in populations asymptomatic for genital tract infection. Therefore, the current clinical criteria for definition of leukocytospermia should be re-assessed in subfertile couples attending a fertility clinic.

Prevalence of sexually transmissible pathogens in semen from asymptomatic male infertility patients with and without leukocytospermia

OBJECTIVE

To determine the prevalence of pathogens that cause sexually transmitted infections (STIs) in semen from asymptomatic male infertility patients with and without leukocytospermia (LCS), and associations between STIs, inflammatory markers, and other semen variables.

DESIGN

Retrospective, controlled study.

SETTING

Academic Medical Center.

PATIENT(S)

Two hundred and forty-one male infertility patients undergoing routine semen analysis: 132 with LCS, and 109 without LCS.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The DNA from STI pathogens (human papillomavirus [HPV], cytomegalovirus [CMV], herpes simplex virus [HSV], human herpesvirus type 6 [HHV-6], Epstein-Barr virus [EBV], hepatitis B virus [HBV], and Chlamydia trachomatis [CT]), routine semen parameters, and markers of accessory gland and epididymal function and inflammation.

RESULT(S)

The DNA from STI pathogens was detected in 45/241 (18.7%) of the samples (CMV, 8.7%; HPV, 4.5%; HHV-6, 3.7%; HSV, 3.7%; CT, 2.5%; EBV, 0.4%; and HBV, 0%), with no difference in prevalence between the LCS and non-LCS groups. The DNA of STI pathogens in semen was associated with a decrease in sperm concentration, motile sperm concentration, total sperm count, and neutral alpha-glucosidase concentration, whereas LCS was associated with a decrease in total sperm count, percent normal forms, and fructose concentration.

CONCLUSION(S)

The DNA of STI pathogens was detected in semen from a high percentage of asymptomatic male infertility patients, and was associated with poor semen quality. Efforts to diagnose and treat subclinical genital-tract infections should be intensified.

Does leukocytospermia associate with poor semen parameters and sperm functions in male infertility? The role of different seminal leukocyte concentrations

To investigate the effect of leukocytospermia on standard semen analysis and sperm function tests such as acrosome reaction, hypoosmotic swelling, antisperm antibody binding and cervical mucus penetration, a prospective clinical study was performed. Two hundred and nineteen male infertility patients undergoing investigation and treatment were included in the study. There was a significant association between acrosome reaction positivity and leukocytospermia according to WHO (World Health Organization) criteria. Increased hypoosmotic swelling test score, higher sperm concentration and enhanced acrosome reaction were closely related to leukocytospermia. When the patients were divided into subgroups according to seminal leukocyte concentrations, acrosome reaction and hypoosmotic swelling were observed to be higher in semen samples with higher leukocyte concentrations compared to those with low seminal leukocyte concentration. In addition, higher sperm concentrations were observed in semen samples with increased leukocyte levels compared to semen samples with low leukocyte levels. These results suggest that leukocytospermia may have a favorable effect on some sperm functions at seminal leukocyte concentrations between 1 and 3x10(6)/ml.

Sperm artificially exposed to antisperm antibodies show altered deoxyribonucleic acid

PURPOSE

Our purpose was to assess sperm deoxyribonucleic acid (DNA) integrity after exposure to antisperm antibodies.

METHODS

Donor semen were divided and exposed to sera containing IgG, IgA, and IgM antisperm antibodies. Untreated portions served as the control. After incubation (1 hr, 23 degrees C), the sperm were centrifuge-washed, resuspended, and incubated (23 degrees C) for 2, 5, 7, or 9 days. Acridine orange staining and kinematic parameters were measured. The sentinel (17q21 from D17S855) and beta-globin genes were amplified and analyzed using denaturing gradient gel electrophoresis.

RESULTS

Sperm preexposed to antisperm antibodies had deleted sentinel gene on days 7 and 9. The beta-globin gene was intact. There were no differences in acridine orange staining.

CONCLUSIONS

Sperm artificially exposed to antisperm antibodies resulted in a subtle deletion of genetic material. The DNA alteration process was slow and was undetectable at the gross level. More studies are needed to confirm the findings and determine whether DNA repair mechanisms can reverse the damage.

A convenient mixed immunobeads screen for antisperm antibodies during routine semen analysis

OBJECTIVE

To determine if leftover unused IgG, IgA, and IgM immunobeads could be combined as a convenient screen for antisperm antibodies in unwashed sperm. For comparisons, the mixed antiglobulin reaction (SpermMar) and immunobead test were performed.

DESIGN

Prospective comparative study.

SETTING

Clinical and academic research environment.

SUBJECT(S)

Donor human sperm negative for antisperm antibodies.

INTERVENTION(S)

Sperm specimens (n = 9) were equally divided and sera with antisperm antibodies added to one portion (positive control).

MAIN OUTCOME MEASURE(S)

Assessment of antisperm antibodies in sperm.

RESULT(S)

The mixed immunobeads screen qualitative results were the same for both the SpermMar and immunobead tests. The mixed immunobeads screen (positive when > or =10% motile sperm was bound) had a sensitivity and specificity of 100%. The percentages of bound sperm for the mixed immunobeads screen correlated with the SpermMar but not the immunobead test. The mixed immunobeads screen intraassay and interassay coefficients of variation were 28.9% and 45.6%, respectively.

CONCLUSION(S)

Matching results between the mixed immunobeads screen and the SpermMar or immunobead test suggested that the screen could be used to detect antisperm antibodies in unwashed sperm. There was no advantage to washing the sperm, although the screen was flexible and applicable for both unwashed and washed sperm.

Sperm separation in patients with urogenital infections

A total of 196 patients attending the Center of Dermatology and Andrology, Giessen, Germany, were examined for fertility problems. Polymorphonuclear elastase, reactive oxygen species (ROS) and the number of round and peroxidase-positive cells were investigated in addition to routine semen analysis. The ejaculates were also analysed before and after sperm separation by means of swim-up or glass wool filtration. In 20 cases of leukocytospermia, sperm concentration, motility, viability, production of reactive oxygen species, and the number of peroxidase-positive cells were evaluated before and after glass wool filtration. The results show that ROS production by viable spermatozoa is highly correlated with the concentration of PMN elastase and the number of both peroxidase-positive and round cells. Multiple regression analysis with motility as dependent parameter showed the number of round cells (n = 91; r = -0.332; P = 0.0030) to be the most important parameter affecting motility, while ROS mainly affects the viability of spermatozoa (n = 69; r = 0.250; P = 0.0107). In the case of leukocytospermia, glass wool filtration significantly reduced the number of peroxidase-positive cells and ROS production (P = 0.0098 and P = 0.0005, respectively). Receiver operating characteristic (ROC) curve analysis for ROS production in the ejaculate using a concentration of 1.000 ng ml-1 PMN elastase as decisive parameter resulted in a cut-off value of 49,489.9 counts 10(-7) viable spermatozoa. The statistical parameters were: Sensitivity: 63.2%, specificity: 100%, positive predictive value: 100%, negative predictive value: 36.1%.

Leucocyte identification and analysis in human semen

The analysis of leucocyte population in human semen could be useful in the diagnosis and therapeutic monitoring of male genital infections, but it is difficult due the low percentage of leucocytes, often not easily recognizable from immature cells of spermatogenesis. A method was developed for the isolation and identification of different leucocyte populations in human semen in healthy subjects using anti-CD45-covered magnetic beads. The seminal fluid was incubated with anti-CD45-covered magnetic beads and the samples were placed in contact with a magnet. The CD45-positive cells recovered were analyzed by light microscopy. The leucocyte formula was compared with a leucocyte formula performed on seminal fluid sediment. The method, even if laborious, eliminates all spermatozoa and most of cells of spermatogenetic lineage, thus permitting phenotyping and functional analysis on isolated leucocytes.

Nonsperm cells in human semen: with special reference to seminal leukocytes and their possible influence on fertility

Nonspermatozoal cells (NSC) in semen, including immature germ cells, leukocytes (WBC) and epithelial cells, are normally found in a concentration less than 15% of the sperm concentration. Cytological staining methods and immunoenzymatic assays for characterization of seminal WBC and methods for detection of various enzymes from WBC are evaluated. Criteria for abnormally high levels of WBC in semen, caused by exogenic factors (e.g., infection) and possibly by endogenic factors (e.g., abnormal sperm), are discussed. Leukocytospermia is associated with reduced in vitro fertilization rate, and experimentally-measured sperm functions (e.g., motility) are inhibited by high concentrations of certain WBC products (e.g., reactive oxygen species and interferon-gamma). At the present stage, the following procedures could be used to evaluate WBC in ejaculates from infertile patients: (1) count the number of NSC using a hemocytometer. (2) Determine the number of WBC in percentage of NSC in smears using the Papanicolaou staining technique, or an immuno-enzymatic assay using monoclonal antibodies to the different kinds of WBC. (3) If, abnormally high levels of WBC (according to the WHO criteria or based on a percentile determined from examination of normal, fertile men) is detected, a second ejaculate should be examined 3 months later. (4) Persistent leukocytospermia should indicate physical and microbiological examinations, after which antibiotic treatment may be indicated.

The biologic significance of white blood cells in semen

OBJECTIVE

To analyze the data available on the biologic significance of white blood cells (WBC) in semen of infertility patients.

DATA RESOURCES

The relevant literature was reviewed.

RESULTS

It is not possible to identify reliably WBC by conventional sperm staining techniques. The peroxidase method is sufficient for quantification of granulocytes, but immunocytology is the gold standard for the detection of all WBC populations in semen. Granulocytes are the most prevalent WBC type in semen (50% to 60%), followed by macrophages (20% to 30%) and T-lymphocytes (2% to 5%). The prevalence of leukocytospermia (> 10(6) WBC/mL semen) among male infertility patients is approximately 10% to 20%. There is controversy on the significance of WBC in semen. Whereas some authors did not observe sperm damage in the presence of leukocytospermia, others have found evidence that WBC are significant cofactors of male infertility: [1] seminal WBC numbers were higher in infertility patients than among fertile men; [2] leukocytospermia was associated with decreased sperm numbers and impaired sperm motility; [3] WBC damaged sperm function and hamster ovum penetration in vitro and were important prognostic factors for IVF-ET failure. Because of absence of clinical symptoms, the origin of WBC is difficult to determine. Normally, most WBC appear to originate from the epididymis because vasectomized men show very few WBC in semen. On the other hand, leukocytospermic samples show low citric acid levels, pointing to asymptomatic prostatitis as a source of WBC in semen. Surprisingly, approximately 80% of leukocytospermic samples are microbiologically negative. In some cases Chlamydia trachomatis might have triggered a persistent inflammatory reaction leading to leukocytospermia. Sperm damage by WBC can be mediated by reactive oxygen species, proteases and cytokines. Furthermore, genital tract inflammation facilitates the formation of sperm antibodies. As seminal plasma has strong anti-inflammatory properties and because there is only short contact between sperm and WBC in prostatitis and seminal vesiculitis, inflammations of the epididymis and testis are likely to have the largest impact on sperm.

CONCLUSIONS

There is ample evidence that WBC can affect sperm function. Further studies are needed to define cofactors that increase or decrease the risk of sperm damage by WBC.