The biologic significance of white blood cells in semen

Oxidative Stress-Associated Male Infertility: Current Diagnostic and Therapeutic Approaches

Infertility is a prevalent global issue affecting approximately 17.5% of adults, with sole male factor contributing to 20-30% of cases. Oxidative stress (OS) is a critical factor in male infertility, disrupting the balance between reactive oxygen species (ROS) and antioxidants. This imbalance detrimentally affects sperm function and viability, ultimately impairing fertility. OS also triggers molecular changes in sperm, including DNA damage, lipid peroxidation, and alterations in protein expression, further compromising sperm functionality and potential fertilization. Diagnostic tools discussed in this review offer insights into OS markers, antioxidant levels, and intracellular ROS concentrations. By accurately assessing these parameters, clinicians can diagnose male infertility more effectively and thus tailor treatment plans to individual patients. Additionally, this review explores various treatment options for males with OS-associated infertility, such as empirical drugs, antioxidants, nanoantioxidants, and lifestyle modifications. By addressing the root causes of male infertility and implementing targeted interventions, clinicians can optimize treatment outcomes and enhance the chances of conception for couples struggling with infertility.

Leukocytospermia and/or Bacteriospermia: Impact on Male Infertility

Infertility is a globally underestimated public health concern affecting almost 190 million people, i.e., about 17.5% of people during their lifetime, while the prevalence of male factor infertility is about 7%. Among numerous other causes, the prevalence of male genital tract infections reportedly ranges between 10% and 35%. Leukocytospermia is found in 30% of infertile men and up to 20% in fertile men. Bacterial infections cause an inflammatory response attracting leukocytes, which produce reactive oxygen species (ROS) and release cytokines, both of which can cause damage to sperm, rendering them dysfunctional. Although leukocytospermia and bacteriospermia are both clinical conditions that can negatively affect male fertility, there is still debate about their impact on assisted reproduction outcomes and management. According to World Health Organization (WHO) guidelines, leukocytes should be determined by means of the Endtz test or with monoclonal antibodies against CD15, CD68 or CD22. The cut-off value proposed by the WHO is 1 × 106 peroxidase-positive cells/mL. For bacteria, Gram staining and semen culture are regarded as the "gold standard", while modern techniques such as PCR and next-generation sequencing (NGS) are allowing clinicians to detect a wider range of pathogens. Whereas the WHO manual does not specify a specific value as a cut-off for bacterial contamination, several studies consider semen samples with more than 103 colony-forming units (cfu)/mL as bacteriospermic. The pathogenic mechanisms leading to sperm dysfunction include direct interaction of bacteria with the male germ cells, bacterial release of spermatotoxic substances, induction of pro-inflammatory cytokines and ROS, all of which lead to oxidative stress. Clinically, bacterial infections, including "silent" infections, are treatable, with antibiotics being the treatment of choice. Yet, non-steroidal antiphlogistics or antioxidants should also be considered to alleviate inflammatory lesions and improve semen quality. In an assisted reproduction set up, sperm separation techniques significantly reduce the bacterial load in the semen. Nonetheless, contamination of the semen sample with skin commensals should be prevented by applying relevant hygiene techniques. In patients where leukocytospermia is detected, the causes (e.g. infection, inflammation, varicocele, smoking, etc.) of the leukocyte infiltration have to be identified and addressed with antibiotics, anti-inflammatories or antioxidants in cases where high oxidative stress levels are detected. However, no specific strategy is available for the management of leukocytospermia. Therefore, the relationship between bacteriospermia and leukocytospermia as well as their specific impact on functional sperm parameters and reproductive outcome variables such as fertilization or clinical pregnancy must be further investigated. The aim of this narrative review is to provide an update on the current knowledge on leukocytospermia and bacteriospermia and their impact on male fertility.

Leukocytospermia does not negatively impact outcomes in in vitro fertilization cycles with intracytoplasmic sperm injection and preimplantation genetic testing for aneuploidy: findings from 5435 cycles

PURPOSE

To investigate whether leukocytospermia (defined as the presence of ≥ 1 × 106 white blood cells/mL) affects clinical and embryologic outcomes in in vitro fertilization (IVF) cycles with intracytoplasmic sperm injection (ICSI) and preimplantation genetic testing for aneuploidy (PGT-A).

METHODS

This was a retrospective cohort study including 5425 cycles between January 2012 to December 2021 at a single large university-affiliated fertility clinic. The primary outcome was live birth rate (LBR).

RESULTS

The prevalence of leukocytospermia was 33.9% (n = 1843). Baseline characteristics including female age, BMI, AMH, Day 3 FSH, and male partner's age were similar in cycles with and without leukocytospermia. The LBR after the first euploid embryo transfer was similar in those with and without leukocytospermia (62.3% vs. 63% p = 0.625). Secondary outcomes including clinical pregnancy rate (CPR), sustained implantation rate (SIR), fertilization (2PN) rate, blastulation rate, and aneuploidy rate were also evaluated. The CPR (73.3% vs 74.9%, p = 0.213) and SIR (64.6% vs. 66%, p = 0.305) were similar in both groups. The 2PN rate was also similar in both groups (85.7% vs. 85.8%, p = 0.791), as was the blastulation rate per 2PN (56.7% vs. 57.5%, p = 0.116). The aneuploidy rate was not significantly different between groups (25.7% vs 24.4%, p = 0.053). A generalized estimation equation with logistic regression demonstrated that the presence leukocytospermia did not influence the LBR (adjusted OR 0.878; 95% CI, 0.680-1.138).

CONCLUSION

Leukocytospermia diagnosed just prior to an IVF cycle with PGT-A does not negatively impact clinical or embryologic outcomes.

Etiology of Male Infertility: an Update

Spermatogenesis is a complex process of germ cell division and differentiation that involves extensive cross-talk between the developing germ cells and the somatic testicular cells. Defective endocrine signaling and/or intrinsic defects within the testes can adversely affect spermatogenic progression, leading to subfertility/infertility. In recent years, male infertility has been recognized as a global public health concern, and research over the last few decades has elucidated the complex etiology of male infertility. Congenital reproductive abnormalities, genetic mutations, and endocrine/metabolic dysfunction have been demonstrated to be involved in infertility/subfertility in males. Furthermore, acquired factors like exposure to environmental toxicants and lifestyle-related disorders such as illicit use of psychoactive drugs have been shown to adversely affect spermatogenesis. Despite the large body of available scientific literature on the etiology of male infertility, a substantial proportion of infertility cases are idiopathic in nature, with no known cause. The inability to treat such idiopathic cases stems from poor knowledge about the complex regulation of spermatogenesis. Emerging scientific evidence indicates that defective functioning of testicular Sertoli cells (Sc) may be an underlying cause of infertility/subfertility in males. Sc plays an indispensable role in regulating spermatogenesis, and impaired functional maturation of Sc has been shown to affect fertility in animal models as well as humans, suggesting abnormal Sc as a potential underlying cause of reproductive insufficiency/failure in such cases of unexplained infertility. This review summarizes the major causes of infertility/subfertility in males, with an emphasis on infertility due to dysregulated Sc function.

An Alternative Application of Magnetic-Activated Cell Sorting: CD45 and CD235a Based Purification of Semen and Testicular Tissue Samples

Magnetic activated cell sorting (MACS) is a well-known sperm selection technique, which is able to remove apoptotic spermatozoa from semen samples using the classic annexinV based method. Leukocytes and erythrocytes in semen samples or in testicular tissue processed for in vitro fertilization (IVF) could exert detrimental effects on sperm. In the current study, we rethought the aforementioned technique and used magnetic microbeads conjugated with anti-CD45/CD235a antibodies to eliminate contaminating leukocytes and erythrocytes from leukocytospermic semen samples and testicular tissue samples gained via testicular sperm extraction (TESE). With this technique, a 15.7- and a 30.8-fold reduction could be achieved in the ratio of leukocytes in semen and in the number of erythrocytes in TESE samples, respectively. Our results show that MACS is a method worth to reconsider, with more potential alternative applications. Investigations to find molecules labeling high-quality sperm population and the development of positive selection procedures based on these might be a direction of future research.

[Infections and male infertility]

BACKGROUND

The role of urogenital infections in male infertility has long been the subject of debate.

METHODS

A bibliographic search limited to English-language literature on human subjects published before 5/2023 resulted in the selection of 189 articles.

RESULTS

Male infertility is often of multifactorial aetiology, and to optimise the prognosis it is important to manage all the factors that can be corrected, including infectious causes, which represent one of the most frequent aetiologies. The infectious agents involved in urogenital infections are most often bacterial or viral, and more rarely parasitic. They can infect the seminal tract, male accessory glands and/or testicles, and usually result in inflammation and increased oxidative stress. These infections reduce male fertility, in particular by altering spermogram parameters and increasing sperm DNA fragmentation. For these reasons, the search for a urogenital infection should be systematic, involving a careful history and clinical examination, ultrasound and systematic bacteriological tests guided by clinical findings. Aetiological treatment may be proposed depending on the picture and the germ involved.

CONCLUSION

This review should help the urologist to establish an accurate diagnosis of the form and extent of the infection, and enable him to define an appropriate therapeutic strategy, tailored to the patient, in order to obtain the best chances of improving male fertility.

Flow cytometric detection and identification of different leukocyte subpopulations in stallion semen

To improve accuracy in evaluating stallion ejaculates, an antibody-based, flow cytometric assay for the detection and identification of leukocyte subpopulations (CD4-, CD8-, CD21-, CD172a-positive cells) in stallion semen (n = 12) was established. For establishment of the assay, native semen was supplemented with blood leukocytes (control: 20% leukocytes, 80% sperm cells) and analysed by flow cytometry. Adding antioxidants (ascorbic acid and butylated hydroxytoluol) to semen immediately after collection inhibited rapid death of lymphoid cells in sperm leukocyte mixtures. In control set-ups, 27.85 ± 5.7% of events were positive for CD4, CD8, CD21 or CD172a, while in native semen samples, leukocytes were scarce (0.114 ± 0.134%). The most abundant leukocyte subpopulation in semen was of lymphoid origin (CD4-positive cells [0.015 ± 0.02%]), whereas CD21-positive cells (B cells; 0.001 ± 0.001%) were virtually absent in ejaculates of fertile stallions. This presented flow cytometric assay for the detection and identification of different leukocyte population in equine antioxidant-treated ejaculates can be used as an additional tool for spermatological examination in stallions.

Evaluation and management of male genital tract infections in the setting of male infertility: an updated review

PURPOSE OF REVIEW

Male infertility may be secondary to male genital tract infection (MGTI) in an estimated 15% of cases. In the absence of overt clinical signs, evaluation for MGTI beyond semen analysis is not well established. Therefore, we review the literature on the evaluation and management of MGTI in the setting of male infertility.

RECENT FINDINGS

A set of international guidelines recommends semen culture and PCR testing, but the significance of positive results remains unclear. Clinical trials evaluating anti-inflammatory or antibiotic treatment report improvements in sperm parameters and leukocytospermia, but data on the effect on conception rates are lacking. Human papillomavirus (HPV) and the novel coronavirus (SARS-CoV-2) have been associated with poor semen parameters and decreased conception rates.

SUMMARY

The finding of leukocytospermia on semen analysis prompts further evaluation for MGTI, including focused physical examination. The role of routine semen culture is controversial. Treatment options include anti-inflammatories; frequent ejaculation; and antibiotics, which should not be used in the absence of symptoms or microbiological infection. SARS-CoV-2 represents a subacute threat to fertility that should be screened for in the reproductive history along with HPV and other viruses.

Analytical validation of five diagnostic tests for the detection of polymorphonuclear cells in stallion semen

The objectives of this study were to evaluate the ability of five diagnostic tests to detect polymorphonuclear cells (PMNs) in stallion semen, and to determine the concentration of PMNs that affects sperm motility. We hypothesized that all tests have diagnostic value, and even low concentrations of PMNs affect motility. One ejaculate was obtained from six stallions. Aliquots of 50 × 10⁶ purified sperm were incubated, in triplicate, with six concentrations of purified PMNs: 1) no PMNs, 2) 0.25 × 10⁶ PMN/ml, 3) 0.5 × 10⁶ PMN/ml, 4) 2.5 × 10⁶ PMN/ml, 5) 5 × 10⁶ PMN/ml, 6) 10 × 10⁶ PMN/ml. The PMNs were quantified using a hemacytometer, cytology, a leucocyte esterase dipstick test (LEDT), a peroxidase test, and CD13 immunolabeling. Sperm motility was evaluated after 4 h at 38 °C. The number of leucocytes detected with the LEDT differed among treatments (P<0.0001), from negative results in control samples to moderate or large numbers in the samples with the highest PMN concentration. The hemacytometer count and CD13 immunostaining detected differences with the control treatment at the lowest PMN concentration (2.5 × 10⁶ PMN/ml; P<0.001). Sperm motion was lower in samples with ≥5 × 10⁶ PMN/ml (P<0.0001). Thus, a sample was considered leucospermic if it contained ≥5 × 10⁶ PMN/ml. The LEDT had the best sensitivity (100%), followed by cytology (78%), peroxidase test (60%), CD13 immunostaining (56%) and hemacytometer count (47%). The LEDT had the lowest specificity (65%), which was 95% for all other tests. In conclusion, the LEDT was a simple, economic and sensitive stall-side test to screen semen for presence of PMNs. Because of the lower specificity, positive LEDT results should be confirmed with the identification of peroxidase-positive cells or CD13-positive cells.

Exploring the Role of Oxidative Stress in Sperm Motility: A Proteomic Network Approach

Significance: Infertility is a major global health problem, with nearly half of the cases being associated with male factors. Although reactive oxygen species (ROS) are crucial for sperm cell normal physiological processes, an imbalance between ROS production and antioxidants can lead to oxidative stress that can impair sperm function. Indeed, high semen ROS levels are reported in 30%-80% of infertile men. Recent Advances: Male oxidative stress infertility is an uprising classification for idiopathic infertility. Proteomic approaches, including quantitative mass spectrometry (MS)-based proteomics, are being utilized to explore the molecular mechanisms associated with oxidative stress in male infertility. Critical Issues: In this review, proteome data were collected from articles available on PubMed centered on MS-based proteomic studies, performed in seminal plasma and sperm cell samples, and enrolling men with impaired semen parameters. The bioinformatic analysis of proteome data with Cytoscape (ClueGO+CluePedia) and STRING tools allowed the identification of the biological processes more prevalent in asthenozoospermia, with focus on the ones related to oxidative stress. Future Directions: The identification of the antioxidant proteins in seminal plasma and sperm cells that can protect sperm cells from oxidative stress is crucial not only for a better understanding of the molecular mechanisms associated with male infertility but specially to guide new therapeutic possibilities. Antioxid. Redox Signal. 37, 501-520.

Reactive Oxygen Species and Their Consequences on the Structure and Function of Mammalian Spermatozoa

Significance: Among the 200 or so cell types that comprise mammals, spermatozoa have an ambiguous relationship with the reactive oxygen species (ROS) inherent in the consumption of oxygen that supports aerobic metabolism. Recent Advances: In this review, we shall see that spermatozoa need the action of ROS to reach their structural and functional maturity, but that due to intrinsic unique characteristics, they are, perhaps more than any other cell type, susceptible to oxidative damage. Recent studies have improved our knowledge of how oxidative damage affects sperm structures and functions. The focus of this review will be on how genetic and epigenetic oxidative alterations to spermatozoa can have dramatic unintended consequences in terms of both the support and the suppression of sperm function. Critical Issues: Oxidative stress can have dramatic consequences not only for the spermatozoon itself, but also, and above all, on its primary objective, which is to carry out fertilization and to ensure, in part, that the embryonic development program should lead to a healthy progeny. Future Directions: Sperm oxidative DNA damage largely affects the integrity of the paternal genetic material to such an extent that the oocyte may have difficulties in correcting it. Diagnostic and therapeutic actions should be considered more systematically, especially in men with difficulties to conceive. Research is underway to determine whether the epigenetic information carried by spermatozoa is also subject to changes mediated by pro-oxidative situations. Antioxid. Redox Signal. 37, 481-500.

Relevance of Leukocytospermia and Semen Culture and Its True Place in Diagnosing and Treating Male Infertility

The current WHO 2010 manual for human semen analysis defines leukocytospermia as the presence of peroxidase-positive leukocytes at a concentration >1×106/mL of semen. Granular leukocytes when activated are capable of generating high levels of reactive oxygen species in semen resulting in oxidative stress. Oxidative stress has been correlated with poor sperm quality, increased level of sperm DNA fragmentation and low fertility potential. The presence of leukocytes and pathogens in the semen may be a sign of infection and/or localized inflammatory response in the male genital tract and the accessory glands. Common uro-pathogens including Chlamydia trachomatis, Ureaplasma urealyticum, Neisseria gonorrhoeae, Mycoplasma hominis, and Escherichia coli can cause epididymitis, epididymo-orchitis, or prostatitis. The relationship between leukocytospermia and infection is unclear. Therefore, we describe the pathogens responsible for male genital tract infections and their association with leukocytospermia. The review also examines the diagnostic tests available to identify seminal leukocytes. The role of leukocytospermia in male infertility and its management is also discussed.

Male Infertility and Oxidative Stress: A Focus on the Underlying Mechanisms

Reactive oxygen species (ROS) play a critical role in defining the functional competence of human spermatozoa. When generated in moderate amounts, ROS promote sperm capacitation by facilitating cholesterol efflux from the plasma membrane, enhancing cAMP generation, inducing cytoplasmic alkalinization, increasing intracellular calcium levels, and stimulating the protein phosphorylation events that drive the attainment of a capacitated state. However, when ROS generation is excessive and/or the antioxidant defences of the reproductive system are compromised, a state of oxidative stress may be induced that disrupts the fertilizing capacity of the spermatozoa and the structural integrity of their DNA. This article focusses on the sources of ROS within this system and examines the circumstances under which the adequacy of antioxidant protection might become a limiting factor. Seminal leukocyte contamination can contribute to oxidative stress in the ejaculate while, in the germ line, the dysregulation of electron transport in the sperm mitochondria, elevated NADPH oxidase activity, or the excessive stimulation of amino acid oxidase action are all potential contributors to oxidative stress. A knowledge of the mechanisms responsible for creating such stress within the human ejaculate is essential in order to develop better antioxidant strategies that avoid the unintentional creation of its reductive counterpart.

The Impact of Oxidative Stress in Male Infertility

At present infertility is affecting about 15% of couples and male factor is responsible for almost 50% of infertility cases. Oxidative stress, due to enhanced Reactive Oxygen Species (ROS) production and/or decreased antioxidants, has been repeatedly suggested as a new emerging causative factor of this condition. However, the central roles exerted by ROS in sperm physiology cannot be neglected. On these bases, the present review is focused on illustrating both the role of ROS in male infertility and their main sources of production. Oxidative stress assessment, the clinical use of redox biomarkers and the treatment of oxidative stress-related male infertility are also discussed.

Deciphering the Nexus Between Oxidative Stress and Spermatogenesis: A Compendious Overview

Oxidative stress (OS) and reactive oxygen species (ROS) are one of the main reasons for the multifactorial concern - male infertility. ROS are active components of cellular metabolism that are intrinsic to cellular functioning and are present at minimal and unreactive levels in normal cells. They are an integral component of the sperm developmental physiology, capacitation, and function. As said "anything in excess is poison," so is the case with ROS. These, when produced in excess to the antioxidants present in the seminal plasma, cause multiple malformations during the process of spermatogenesis such as lipid peroxidation, interfere with capacitation, sperm DNA fragmentation and damage to the membrane of the sperm which in turn reduces the motility of the sperm and its ability to fuse with the oocyte. Exposure of spermatozoa to oxidative stress is a major causative agent of male infertility. Thus, a delicate balance between the beneficial and detrimental effects of ROS for proper functions is of utter importance. In this chapter, the influence of ROS in OS which is a key player in male infertility along with the diagnosis, available treatment, and prevention of extensive ROS buildup within the spermatozoa are highlighted.

The Role of Male Reproductive Organs in the Transmission of African Swine Fever-Implications for Transmission

African swine fever (ASF) has evolved from an exotic animal disease to a threat to global pig production. An important avenue for the wide-spread transmission of animal diseases is their dissemination through boar semen used for artificial insemination. In this context, we investigated the role of male reproductive organs in the transmission of ASF. Mature domestic boars and adolescent wild boars, inoculated with different ASF virus strains, were investigated by means of virological and pathological methods. Additionally, electron microscopy was employed to investigate in vitro inoculated sperm. The viral genome, antigens and the infectious virus could be found in all gonadal tissues and accessory sex glands. The viral antigen and viral mRNAs were mainly found in mononuclear cells of the respective tissues. However, some other cell types, including Leydig, endothelial and stromal cells, were also found positive. Using RNAScope, p72 mRNA could be found in scattered halo cells of the epididymal duct epithelium, which could point to the disruption of the barrier. No direct infection of spermatozoa was observed by immunohistochemistry, or electron microscopy. Taken together, our results strengthen the assumption that ASFV can be transmitted via boar semen. Future studies are needed to explore the excretion dynamics and transmission efficiency.

Papanicolaou-Stained Cytosmear Preparations in the Evaluation of Leucocytospermia: A Tertiary Centre Experience and Assessment of Utility

Objectives Leucocytospermia is a rare cause of infertility with a variable incidence in infertile men. In many andrology laboratories, semen analysis is primarily centered on analyzing basic parameters (sperm count, motility, and viability). We examined the role of cytomorphological analysis on Papanicolaou (PAP)-stained smears in the work up of male infertility, with special reference to leukocytospermia and assessed the morphological features of sperms in these cases. Materials and Methods All cases signed out as "leukocytospermia" between November 2017 and January 2018 were evaluated. Cases showing pus cells (≥ 1/5hpf) on cytosmear evaluation were also analyzed. Parameters obtained on modified Neubauer's chamber, wet mount preparations, and autoanalyzer SQA-IIC-P (Medical Electronic Systems, Israel) were tabulated. PAP-stained smears were examined to assess morphological defects and other findings, if any. Results Out of 348 semen samples, 6 (1.72%) were diagnosed as leukocytospermia, all displaying pus cells on cytomorphological evaluation. Five cases having white blood cells < 1 × 10 ⁹ /L were analyzed, which displayed the presence of pus cells (≥ 1/5 hpf) on cytosmear preparations (1.43%). Nine cases (81.8%) showed reduced motile sperm concentration, functional sperm concentration, and sperm motility index. Morphological evaluation of the PAP-stained smears showed mid-piece defects in 18.1% cases. Conclusion Diligent cytomorphological evaluation of semen is essential to diagnose leukocytospermia, assess morphological defects, and serve as a quality control measure.

Oxidative Stress, Testicular Inflammatory Pathways, and Male Reproduction

Inflammation is among the core causatives of male infertility. Despite male infertility being a serious global issue, "bits and pieces" of its complex etiopathology still remain missing. During inflammation, levels of proinflammatory mediators in the male reproductive tract are greater than usual. According to epidemiological research, in numerous cases of male infertility, patients suffer from acute or chronic inflammation of the genitourinary tract which typically occurs without symptoms. Inflammatory responses in the male genital system are inextricably linked to oxidative stress (OS). OS is detrimental to male fertility parameters as it causes oxidative damage to reproductive cells and intracellular components. Multifarious male infertility causative factors pave the way for impairing male reproductive functions via the common mechanisms of OS and inflammation, both of which are interlinked pathophysiological processes, and the occurrence of any one of them induces the other. Both processes may be simultaneously found in the pathogenesis of male infertility. Thus, the present article aims to explain the role of inflammation and OS in male infertility in detail, as well as to show the mechanistic pathways that link causative factors of male reproductive tract inflammation, OS induction, and oxidant-sensitive cellular cascades leading to male infertility.

Can leukocytospermia predict prostate cancer via its effects on mitochondrial DNA?

Leukocytospermia was previously reported to affect sperm quality by the production of reactive oxygen species (ROS) leading to oxidative stress (OS). In turn, OS decreases sperm functional integrity, increases sperm DNA damage and ultimately alters fertility status. To elucidate the impact of leukocytospermia on sperm nuclear DNA integrity and mitochondrial DNA (mtDNA) structure, we conducted a study including 67 samples from infertile patients with low level of leucocytes (Group 1: n = 20) and with leukocytospermia (Group 2: n = 47). In addition to standard sperm parameters' assessment, we measured the levels of inflammation biomarkers [interleukin-6 (IL-6) and interleukin-8 (IL-8)] and evaluated the oxidative status [malondialdehyde (MDA) and enzymatic and non-enzymatic antioxidants]. In addition, we evaluated the level of sperm nuclear DNA fragmentation and analysed mitochondrial DNA (mtDNA) of sperm cells by sequencing of 5 genes [cytochrome oxidase I (COXI), cytochrome oxidase II (COXII), cytochrome oxidase III (COXIII), adenosine triphosphate synthase 6 (ATPase 6) and adenosine triphosphate synthase 8 (ATPase 8)]. As expected, patients with leukocytospermia had significantly higher MDA levels (32.56 ± 24.30 nmole/ml) than patients without leukocytospermia (17.59 ± 9.60 nmole/ml) (p < .018). Also, sperm DNA fragmentation index (DFI) was significantly higher in Group 2 (33.05 ± 18.14%) as compared to Group 1 (14.19 ± 9.50%) (p < .001). The sequencing of mtDNA revealed a high number of substitutions in Group 2 (n = 102) compared to Group 1 (n = 5). These substitutions were observed mainly in COXI. Among COXI substitutions found in Group 2, twelve changes were previously described in patients with prostate cancer and six of them were shown associated with this pathology. These findings suggest that leukocytospermia may predispose to the manifestation of prostate cancer through modification of mitochondrial DNA and this may be promoted by OS.

Myeloperoxidase inhibitor AZD5904 enhances human sperm function in vitro

STUDY QUESTION

Does AZD5904, a myeloperoxidase inhibitor (MPOi), have any effect on human sperm function in vitro?

SUMMARY ANSWER

AZD5904 improves sperm function in an in vitro model of oxidative stress (OS) and potentially offers a novel treatment approach for male infertility.

WHAT IS KNOWN ALREADY

Male infertility is an underlying or contributory cause in half of all couples experiencing difficulties conceiving, yet there is currently no effective treatment or cure. OS is a common pathology in a significant proportion of infertile men. It can negatively affect sperm motility and the ability to fertilize a mature oocyte, as well as DNA integrity, and therefore represents an attractive target for therapeutic intervention.

STUDY DESIGN, SIZE, DURATION

This study included population-based samples from men (23-50 years) attending Ninewells Assisted Conception Unit, Dundee for diagnostic semen analysis, July 2017-September 2018. Semen samples (n = 47) from 45 patients were used.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Neutrophils activated using zymosan were incubated with prepared human spermatozoa for 2 h (T2) and 24 h (T24) to create an in vitro model of OS. Parallel samples were co-incubated with AZD5904, an MPOi, to examine its effects. Sperm motility was assessed by computer-assisted sperm analysis at T2 and T24. Functional motility was assessed by sperm penetration assay. Statistical analysis was performed using GraphPad Prism.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no significant difference in total or progressive sperm motility between any treatment and control groups at T2 or T24. Nonetheless, significant positive effects on sperm function were observed with AZD5904, with 16/45 (35.6%) samples (with both normal and abnormal baseline semen analysis characteristics) displaying a ≥20% increase in sperm penetrated through viscous media (P < 0.003).

LIMITATIONS, REASONS FOR CAUTION

This was an in vitro study.

WIDER IMPLICATIONS OF THE FINDINGS

Treatment with AZD5904 resulted in significant increased sperm penetration in one of three samples treated, which is likely to represent improvement in sperm function required for fertilization. We are now planning a clinical trial to validate these results and hope that this could represent a new treatment for male infertility.

STUDY FUNDING/COMPETING INTEREST(S)

AZD5904 was shared through the AstraZeneca Open Innovation program. The study was funded by AstraZeneca and sponsored by the University of Dundee. Additional funding was provided by Chief Scientist Office/NHS Research Scotland (S.J.M.d.S.). A.W. and H.J.S. are both full time employees of AstraZeneca. A.W. and H.J.S. are inventors on a patent filed by AstraZeneca titled MPOi for use in medicine which includes MPOi for use in the treatment of male infertility (WO 2019/016074 Al). S.J.M.d.S. is Associate Editor of Human Reproduction and Editorial Board member of Reproduction & Fertility. C.L.R.B. is Editor of RBMO and has received lecturing fees from Merck and Ferring and is on the Scientific Advisory Panel for Ohana BioSciences. C.L.R.B. was chair of the World Health Organization Expert Synthesis Group on Diagnosis of Male infertility (2012-2016). C.L.R.B. has a patent WO2013054111 A1 issued. The other authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Effect of macrophages in semen on sperm quality

BACKGROUND

This was a cross-sectional study in China which analyzed the levels of macrophages (Mφ) in semen and evaluated the influence of Mφ levels in semen on sperm quality.

METHODS

The subjects involves 78 males, 25- to 35-year old. The samples were divided into a low group (Mφ < 6 × 105/ml) and a high group (Mφ > 6 × 105/ml). Evaluation included consideration of the influencing factors of male semen quality, macrophage concentration, sperm motility, morphology, membrane integrity DNA fragmentation index (DFI), anti-sperm antibodies (AsAb), IL-10, and IL-12 in semen.

RESULTS

There was no difference in the physical or chemical indices of the semen, sperm concentration, AsAb, IL-10, or IL-12 between the two groups (P > 0.05). The percentage of sperm forward motility (PR%), the rate of normal sperm shape, and the integrity of cell membranes in the low group were higher than those in the high group (P < 0.05), while the percentage of sperm inactivity (IM%), the rate of sperm head deformity, the rate of deformity in the neck and middle segment, the sperm deformity index (SDI), the teratozoospermia index (TZI), and the sperm DFI in the low group were lower than those in the high group (P < 0.05). The concentration of Mφ in the semen was linearly correlated with sperm concentration, sperm PR%, IM%, sperm normal shape rate, head deformity rate, neck and middle deformity rate, SDI, TZI, sperm DFI, and sperm cell membrane integrity (P < 0.05), but there was no linear correlation with IL-10 or IL-12 (P > 0.05).

CONCLUSIONS

The Mφ concentration in semen is not significantly correlated with semen volume or sperm concentration, but negatively correlated with sperm motility, morphology, cell membrane integrity, and DNA damage rate. There is no significant correlation between the macrophages and the concentration of IL-10 or IL-12.

Inertial Microfluidics Enabling Clinical Research

Fast and accurate interrogation of complex samples containing diseased cells or pathogens is important to make informed decisions on clinical and public health issues. Inertial microfluidics has been increasingly employed for such investigations to isolate target bioparticles from liquid samples with size and/or deformability-based manipulation. This phenomenon is especially useful for the clinic, owing to its rapid, label-free nature of target enrichment that enables further downstream assays. Inertial microfluidics leverages the principle of inertial focusing, which relies on the balance of inertial and viscous forces on particles to align them into size-dependent laminar streamlines. Several distinct microfluidic channel geometries (e.g., straight, curved, spiral, contraction-expansion array) have been optimized to achieve inertial focusing for a variety of purposes, including particle purification and enrichment, solution exchange, and particle alignment for on-chip assays. In this review, we will discuss how inertial microfluidics technology has contributed to improving accuracy of various assays to provide clinically relevant information. This comprehensive review expands upon studies examining both endogenous and exogenous targets from real-world samples, highlights notable hybrid devices with dual functions, and comments on the evolving outlook of the field.

Oxidative stress and male infertility

BACKGROUND

Between 30% and 80% of patients with male infertility produce excessive reactive oxygen species (ROS) in their ejaculate even though the cause of male infertility is unexplained in approximately half of cases. The strong connection between oxidative stress (OS) and male infertility has led recent investigators to propose the term "Male Oxidative Stress Infertility (MOSI)" to describe OS-associated male infertility.

METHODS

We searched the PubMed database for original and review articles to survey the effects of OS on male infertility, and then verified the effects and treatments.

MAIN FINDINGS

Seminal plasma contains many antioxidants that protect sperm from ROS, because low amounts of ROS are required in the physiological fertilization process. The production of excessive ROS causes OS which can lower fertility through lipid peroxidation, sperm DNA damage, and apoptosis. Several assays are available for evaluating OS, including the MiOXSYS® analyzer to measure oxidation-reduction potential. Several measures should be considered for minimizing OS and improving clinical outcomes.

CONCLUSION

Accurately diagnosing patients with MOSI and identifying highly sensitive biomarkers through proteomics technology is vital for better clinical outcomes.

Nonsurgical Management of Oligozoospermia

Male infertility secondary to oligozoospermia is surprisingly common. Although a majority of cases are idiopathic, oligozoospermia can be caused by endocrine dysfunction, anatomic abnormalities, medications, or environmental exposures. The work-up includes excluding reversible factors such as hormonal deficiency, medication effects, and retrograde ejaculation and identifying any underlying genetic syndrome and treating reversible medical causes. If no reversible cause is found, appropriate referrals to urology and assisted reproductive technology should be initiated. Lastly, clinicians should be aware of and respond to the psychological and general health ramifications of a diagnosis of oligozoospermia as part of the comprehensive care of men and couples struggling with a diagnosis of infertility.

Chemical Composition and Antimicrobial Activity of Selected Essential Oils against Staphylococcus spp. Isolated from Human Semen

Staphylococcus spp. is not only a commensal bacteria but also a major human pathogen that causes a wide range of clinical infections. Recent evidence suggests that Staphylococcus has the ability to colonize the reproductive system and to affect its structure and functions. The objective of this study was to determine the chemical properties and antibacterial effects of select essential oils (EOs): Amyris balsamifera L., Boswellia carterii Birdw., Canarium luzonicum (Blume) A. Gray, Cinnamomum camphora (L.) J. Presl., Cinnamomum camphora var. linaloolifera Y. Fuita, Citrus x aurantium L., Gaultheria procumbens L., Litsea cubeba (Lour.) Pers., Melaleuca ericifolia Smith., Melaleuca leucadendra L., Pogostemon cablin (Blanco) Benth., Citrus limon (L.) Osbeck, Santalum album L., and Vetiveria zizanoides (L.) Roberty against 50 Staphylococcus spp. cultures isolated from human semen, specifically Staphylococcus aureus, S. capiti, S. epidermidis, S. haemoliticus, and S. hominis. The disc diffusion and broth microdilution methods were used to assess the antimicrobial potential and to determine the minimum inhibitory concentration (MIC) of the selected EOs. The best anti-Staphylococcus activities were found with both methods for the essential oils of C. luzonicum (Blume) A. Gray, A. balsamifera, C. camphora, and P. cabli.

Reactive Oxygen Species Secreted by Leukocytes in Semen Induce Self-Expression of Interleukin-6 and Affect Sperm Quality

Reproductive tract inflammation is considered an important cause of male infertility. Increased leukocytes in semen can produce many reactive oxygen species (ROS), which affect sperm function. The aim of this study is to identify the main source of ROS in seminal plasma and to assess the effect of ROS on leukocytes. Semen samples (n = 20) with leukocyte concentration >1 × 10⁶ were collected from a male infertility clinic. This study mainly compares the sperm function parameters of the normal group and the semen white blood cell group >1 × 10⁶. The results identified that ROS in semen was closely related to sperm function parameters, and CD45⁺ leucocytes were the main source of ROS. Compared with the control group, the concentration of IL-2, IL-4, IL-6, IFN-γ, and TNF-α was higher in the experimental group. Leukocytes in semen may regulate the secretion of ROS through the mammalian target of rapamycin (mTOR) pathway. A considerable amount of ROS can upregulate the expression of IL-6 in leukocytes via the nuclear factor kappa-B (NF-kB) pathway.

Myeloperoxidase and lactoferrin expression in semen fluid: Novel markers of male infertility risk?

RESEARCH QUESTION

Infections and/or inflammation processes of male genital tract are highly prevalent and often associated with risk of infertility. These conditions represent a possible cause of leukocytospermia, which is still under debate. Leukocytes are key-factors to reactive oxygen species (ROS) production and the increase of ROS in semen fluid is associated with the worsening of semen parameters. At present, there are not appropriate andrological tests to identify asymptomatic inflammatory conditions when the amount of leukocytes is in the normal range.

DESIGN

We studied the innate immunity profile of myeloperoxidase and lactoferrin (MPO/LAC) proteins expressed in the semen fluid of 39 men evaluated for couple infertility, in the absence of leukocytospermia.

RESULTS

The presence of both MPO and LAC proteins was associated with a decrease of sperm concentration and of progressive/total motility, whereas the increase of MPO-/LAC + indicated a worse sperm morphology. It is worth to report the predictive potential of MPO+/LAC + pattern (above 4.36 %) as a biological marker to distinguish normozoospermic from pathological patients.

CONCLUSION

Our findings indicate MPO/LAC analysis as a potential diagnostic tool to identify asymptomatic conditions eventually related to male infertility, even when the number of leukocytes in semen fluid is below 1 million/mL.

Epididymal contribution to male infertility: An overlooked problem

The diagnosis and treatment of male infertility, excluding assisted conception, are limited because of, but not limited to, poor understanding of sperm post-testicular development and storage. Many may think that sperm dysfunction is only self-contained in the sperm cell itself as a result of defective spermatogenesis. However, it can also be a consequence of inadequate epididymal maturation following disorders of the epididymis. Improper epididymal functions can disturb semen parameters and sperm DNA integrity, result in high leucocyte concentrations and high numbers of immature germ cells and debris or even cause idiopathic infertility. To date, the data are limited regarding critical markers of sperm maturation and studies that can identify such markers for diagnosis and managing epididymal dysfunction are scarce. Therefore, this article aims to draw attention to recognise a disturbed epididymal environment as a potential cause of male infertility.

Viruses in the reproductive tract: On their way to the germ line?

Studies of vertebrate genomes have indicated that all species contain in their chromosomes stretches of DNA with sequence similarity to viral genomes. How such 'endogenous' viral elements (EVEs) ended up in host genomes is usually explained in general terms such as 'they entered the germ line at some point during evolution'. This seems a correct statement, but is also rather imprecise. The vast number of endogenous viral sequences suggest that common routes to the 'germ line' may exist, as relying on chance alone may not easily explain the abundance of EVEs in modern mammalian genomes. An increasing number of virus types have been detected in human semen and a growing number of studies have reported on viral infections that cause male infertility or subfertility and on viral infections that threaten in vitro fertilisation practices. Thus, it is timely to survey the pathway(s) that viruses can use to gain access to the human germ line. Embryo transfer and semen quality studies in livestock form another source of relevant information because virus infection during reproduction is clearly unwanted, as is the case for the human situation. In this review, studies on viruses in the male and female reproductive tract and in the early embryo will be discussed to propose a plausible viral route to the mammalian germ line.

The role of infections and leukocytes in male infertility

Declining birth rates are one of the problems facing society today. Male counterparts are responsible for about half of the infertility cases, and genitourinary tract infections may play a contributing role in approximately 15% of male infertility cases. Leukocytospermia is an established indicator of infection in the male urogenital tract, although other microorganisms such as bacteria and virus may also be contributors to the etiology of male infertility. The pathophysiology of these infectious agents may be initiated by a local inflammatory reaction resulting in an increase in reactive oxygen species (ROS). This results in testicular injury, thereby affecting sperm morphology, sperm motility, sperm viability and elevation of the seminal leukocyte as a result of the genital tract infection. The infectious and inflammatory changes can result in male infertility. It is proposed that high concentrations of seminal leukocyte and infectious agents may affect sperm function resulting in clumping of motile spermatozoa, decreasing acrosomal functionality and also causing alterations in sperm morphology. However, the literature has poorly clarified the role of infection in male infertility, provoking further debate and research on this topic.

Natural killer and NKT cells in the male reproductive tract

Natural killer (NK) cells are important effector lymphocytes that play a pivotal role in the innate and adaptive immune responses to tumors and viral infection. NKT cells are a heterogeneous group of T cells that share properties with both T cells and NK cells. They display immunoregulatory properties as they facilitate the cell-mediated immune response to tumors and infectious diseases, and inhibit cell-mediated immunity associated with autoimmune diseases and allograft rejection. However, the roles of NK and NKT cells in the male reproductive tract remain largely unexplored, in particular, NKT cells, tissue distribution, and state of health or disease. Infection and inflammation of the male genital tract are thought to be the primary etiological factors of male infertility. In this review, we considered this complex and rapidly growing field. We summarize the recent findings and the characterization and roles of NK and NKT cells in the male reproductive tract, including the testis, epididymis, prostate, seminal vesicle, and semen, to enhance our understanding of the immunological mechanisms of male infertility and for the design effective vaccines for male reproductive health in the future.

The importance of semen leukocytes in HIV-1 transmission and the development of prevention strategies

HIV-1 sexual transmission occurs mostly through contaminated semen, which is a complex mixture of soluble factors with immunoregulatory functions and cells. It is well established that semen cells from HIV-1-infected men are able to produce the virus and that are harnessed to efficiently interact with mucosal barriers exposed during sexual intercourse. Several cofactors contribute to semen infectivity and may enhance the risk of HIV-1 transmission to a partner by increasing local HIV-1 replication in the male genital tract, thereby increasing the number of HIV-1-infected cells and the local HIV-1 shedding in semen. The introduction of combination antiretroviral therapy has improved the life expectancy of HIV-1 infected individuals; however, there is evidence that systemic viral suppression does not always reflect full viral suppression in the seminal compartment. This review focus on the role semen leukocytes play in HIV-1 transmission and discusses implications of the increased resistance of cell-mediated transmission to immune-based prevention strategies.

Laboratory and clinical management of leukocytospermia and hematospermia: a review

Leukocytospermia and hematospermia are defined as the presence of abnormally high white blood cell and red blood cell concentration in the semen, respectively. Numerous etiologies and various implications on fertility have been identified. In a small proportion of men, the presence of white blood cells or red blood cells can adversely affect sperm quality by the production of reactive oxygen species. Several methods have been used to assess the presence of white blood cells and red blood cells in samples, such as identification of round cells, immunohistochemical staining using monoclonal antibodies, the Endtz test, the peroxidase test, and flow cytometry or microscopy. In addition, techniques have been identified to separate sperm samples from white blood cells and red blood cells for cryopreservation to improve outcomes in assisted reproductive technology. In this review, laboratory and clinical management of leukocytospermia and hematospermia are discussed. Currently available diagnostic methods and treatment options are outlined, and available optimal cryopreservation techniques for samples with white blood cells or red blood cells are summarized.

Seminal oxidation-reduction potential levels are not influenced by the presence of leucocytospermia

Oxidative stress (OS) is characterised by an excessive amount of reactive oxygen species (ROS) which negatively affect sperm functions. In this study, the influence of leucocytes on seminal oxidation-reduction potential (ORP) and sperm DNA fragmentation (SDF) was investigated in 1,068 men. Seminal leucocyte concentration did not correlate with SDF, unadjusted ORP, ORP normalised for sperm concentration (sORP), ORP normalised for total motile sperm concentration (motORP) or total motile sperm count (TMSC-ORP). Although receiver operator characteristic (ROC) curve analyses show that leucocytospermia does not predict high sORP values (>1.34 mV/10⁶ spermatozoa/ml), the motORP (AUC: 0.666) and TMSC-ORP (AUC: 0.683) predict the rate of leucocytospermia significantly (p = .0195 and p = .0085 respectively). Moreover, SDF can significantly predict leucocytospermia (AUC: 0.679; p = .011) and vice versa (AUC: 0.657, p = .0298). Our data confirm the association between OS and SDF. In conclusion, motORP and TMSC-ORP may be better predictive factors of leucocytospermia, probably because sperm motility, included in motORP and TMSC-ORP calculation, is the first seminal parameter to be affected by OS. Although all these parameters are indicative of OS, ORP values, SDF and leucocytospermia should be considered independently for the evaluation of redox seminal status, as they probe distinct seminal features.

MALDI MS Analysis to Investigate the Lipid Composition of Sperm

Background:

The sperm plasma membrane meets the requirements of sperm transit through the female genital tract and subsequent fertilization. Commonly, the (phospho)lipid composition of sperm is characterized by tremendous amounts of highly unsaturated fatty acyl residues such as docosahexaenoic and docosapentaenoic acid. While human sperm contain almost exclusively diacyl lipids, many animal sperm additionally contain significant amounts of ether lipids such as alkylacyl- and alkenyl-acyl lipids (plasmalogens).

Hypothesis/Objective:

It is suggested that deviations from the typical lipid composition are indicative of pathological changes. Therefore, simple methods to elucidate the sperm lipid composition are essential.

Method:

Matrix-assisted laser desorption and ionization (MALDI) mass spectrometry (MS) is a fast and simple method. Since the selection of the most suitable matrix is a crucial step in MALDI MS, this topic will be highlighted. It will also be shown that MALDI MS can be easily combined with thin-layer chromatography to overcome ion suppression effects.

Results:

The lipid composition of sperm from different species can be elucidated by MALDI MS. However, different matrix compounds have to be used to record positive and negative ion mass spectra. Since some sperm (glyco)lipids are characterized by the presence of sulfate residues which suppress the detection of less acidic lipids in the negative ion mode, previous separation is often necessary. It will be also emphasized that plasmalogens can be easily identified by either enzymatic digestion or treatment with acids.

Conclusion:

MALDI MS is a reliable method to obtain sperm lipid fingerprints in a simple and convenient way.

From Past to Present: The Link Between Reactive Oxygen Species in Sperm and Male Infertility

Reactive oxygen species (ROS) can be generated in mammalian cells via both enzymatic and non-enzymatic mechanisms. In sperm cells, while ROS may function as signalling molecules for some physiological pathways, the oxidative stress arising from the ubiquitous production of these compounds has been implicated in the pathogenesis of male infertility. In vitro studies have undoubtedly shown that spermatozoa are indeed susceptible to free radicals. However, many reports correlating ROS with sperm function impairment are based on an oxidative stress scenario created in vitro, lacking a more concrete observation of the real capacity of sperm in the production of ROS. Furthermore, sample contamination by leukocytes and the drawbacks of many dyes and techniques used to measure ROS also greatly impact the reliability of most studies in this field. Therefore, in addition to a careful scrutiny of the data already available, many aspects of the relationship between ROS and sperm physiopathology are still in need of further controlled and solid experiments before any definitive conclusions are drawn.

The association of seminal leucocytes, interleukin-6 and interleukin-8 with sperm DNA fragmentation: A prospective study

The effect of seminal leucocytes on sperm DNA integrity has been discussed controversially in literatures. Moreover, the studies investigating the in vivo effect of pro-inflammatory cytokines interleukin-6 and interleukin-8 on sperm DNA fragmentation are scarce and inconsistent. The association of standard sperm parameters with sperm DNA fragmentation is also a matter of ongoing discussion. Hence, the aims of this study were, first, to evaluate the effect of seminal leucocytes, interleukin-6 and interleukin-8 on sperm DNA integrity and, second, to examine whether standard semen parameters are associated with sperm DNA fragmentation. Seminal leucocytes, interleukin-6, interleukin-8 and standard semen parameters, including total sperm number, sperm concentration, progressive motility, nonprogressive motility, immotility and normal morphology, were determined in 134 consecutive men. The concentrations of seminal leucocytes, interleukin-6 and interleukin-8, did not correlate with sperm DNA fragmentation. In contrast, total sperm number, sperm concentration, progressive motility, nonprogressive motility and normal morphology exhibited significant inverse correlations with sperm DNA fragmentation. Immotile spermatozoa were directly correlated with sperm DNA fragmentation. In conclusion, seminal leucocytes, interleukin-6 and interleukin-8, are not associated with sperm DNA fragmentation. Poor standard semen parameters are significantly related to the high levels of sperm DNA fragmentation.

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.

Round cells do not contaminate or mask human sperm proteome in proteomic studies using cryopreserved samples

Semen contains leucocytes and round cells, besides spermatozoa. The objective of this study was to identify whether the proteins from round cells and leucocytes affect the proteomic analysis of spermatozoa. Cryopreserved human sperm samples were divided into four groups: (1) samples with ≥1 × 10⁶ /ml leucocytes unprocessed; (2) samples with ≥1 × 10⁶ /ml leucocytes processed by 65% density centrifugation; (3) samples with round cells <1 × 10⁶ /ml unprocessed; and (4) samples with round cells <1 × 10⁶ /ml processed by 65% density centrifugation. Samples from each group (1, 2, 3 and 4) were pooled (n = 5) for quantitative proteomic analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Comparative analysis revealed nine differentially expressed proteins (DEPs) groups 1 and 2. Moreover, five DEPs were identified between groups 3 and 4. We observed that cylicin-1, Atlastin-1 and vesicle transport protein SFT2B are specific to spermatozoa, and none of them were associated with leucocytes. The number of DEPs in spermatozoa of processed and unprocessed cryopreserved semen samples was negligible. Our results indicate that the presence of round cells (<1 × 10⁶ /ml) in the seminal ejaculation does not interfere in the accurate detection of spermatozoa proteome by LC-MS/MS.

Oxidation reduction potential: a new biomarker of male infertility

Oxidative stress is considered a major etiology for male infertility, more specifically idiopathic infertility. The causes of seminal oxidative stress can be intrinsic, such as varicocele or due to the presence of active leukocytes and immature germ cells. Reported external causes are smoking, alcohol or exposure to environmental toxins. Traditional methods to determine the seminal oxidative stress do not evaluate this status directly, but rather measure its components or intermediate products indirectly, instead. The major disadvantages of the traditional methods are related with time and cost as these methods are extremely time consuming and require expensive equipment, consumables and highly skilled laboratory personnel. To overcome these drawbacks, the MiOXSYS® system, a method which directly measures the oxidation-reduction potential (ORP), was developed. The evaluation of the ORP using MiOXSYS® is cost-effective, easy and quick. However, this newly introduced method to evaluate the oxidative status of semen still requires validation in different andrology laboratory settings across the world.

Impact of asymptomatic genital tract infections on in vitro Fertilization (IVF) outcome

Background

Infertility is estimated to affect approximately 9–30% of reproductive-aged couples. Several conditions involving one or both partners may contribute to infertility. The aim of this study is to evaluate the role of asymptomatic genital tract infections in the outcome of In Vitro Fertilization (IVF) in couples with infertility.

Methods

A total of 285 infertile couples were enrolled in the study. Vaginal/endocervical swabs and semen samples were collected and subjected to microbiological analysis. Spermiograms were carried out on semen specimens, and lactobacilli were quantified in vaginal swabs. Data were associated with IVF results and analysed by using non parametric tests and multivariate analysis.

Results

Microbiological analysis showed that 46.3% of couples presented with an asymptomatic genital tract infection. Spermiogram results showed a significantly diminished motility of sperm cells in samples positive to microbiological testing compared to negative specimens. Enterococcus faecalis was the most prevalent species (11.6%) in positive semen samples and was found to negatively affect both sperm morphology (p = 0.026) and motility (p = 0.003). Analysis of genital swabs from females showed that the presence of E. faecalis (p<0.0001), Escherichia coli (p = 0.0123), Streptococcus agalactiae (p<0.0001), and Gardnerella vaginalis (p = 0.0003) was significantly associated to reduced levels of vaginal lactobacilli. Association of microbiological data with IVF outcome showed that 85.7% of IVF+ couples was microbiologically negative, while IVF was successful in just 7.5% of couples infected with E. faecalis and/or U. urealyticum and/or M. hominis (p = 0.02).

Conclusions

The results show the negative impact of E. faecalis on sperm quality and the association of definite bacterial pathogens with reduced levels of vaginal lactobacilli. The presence of E. faecalis and/or U. urealyticum and/or M. hominis in genital samples of infertile couples is predictive for a negative outcome of IVF.

Chronic epididymitis and Grade III varicocele and their associations with semen characteristics in men consulting for couple infertility

Chronic epididymitis and varicocele are frequently observed genital disorders in men consulting for couple infertility, but their impact on semen characteristics at the time of infertility consultation is still a matter of debate. We investigated 652 male partners of couples who had their first infertility consultation between 1999 and 2015 in Argentina. Men with chronic epididymitis (n = 253), Grade III varicocele (n = 106), and both conditions (n = 125) were compared with a control group (n = 168) composed of men without these disorders or any other recognized causes of male infertility. We showed that men who presented isolated chronic epididymitis were more likely to have high percentages of low sperm motility and abnormal sperm morphology as well as a high number of white blood cells. Men with isolated Grade III varicocele had low sperm production and motility and an increased percentage of abnormal sperm morphology. Finally, men who simultaneously presented chronic epididymitis with Grade III varicocele had a low sperm motility and increased percentage of abnormal sperm morphology as well as a high number of white blood cells. Physical examination of the genital organs may identify common disorders, potentially involved as causal factors of patient's infertility. These disorders are associated with specific seminal profiles that should help in identifying the best treatment from the available therapeutic options, effectiveness, safety, and allowing as much as possible natural conception.