Predictive value of testicular histology in secretory azoospermic subgroups and clinical outcome after microinjection of fresh and frozen-thawed sperm and spermatids

Rate of testicular histology failure in predicting successful testicular sperm extraction

Background

The management of Non-Obstructive (NOA) Azoospermia or Obstructive Azoospermia (OA) patients relies on testicular sperm extraction (TESE) followed by intracytoplasmic sperm injection (ICSI). In NOA patients the sperm recovery is successful in only 50% of cases and therefore the ability to predict those patients with a high probability of achieving a successful sperm retrieval would be a great value in counselling the patient and his partner. Several studies tried to suggest predictors of a positive TESE (e.g. FSH concentration), but most concluded that diagnostic testicular biopsy (histology) is best.

Methods

This is a retrospective analysis of 526 TESE patients. After the extraction of the testis, the resulting sample was immediately given to the embryologist, who examined the tubules for sperm cryopreservation. During the same procedure, a different specimen was destined to the histological analysis. The comparison between the two methodological approaches was carried out through a score.

Results

Concordance between TESE and testicular histology outcomes was found in 70,7% of patients; discordance was found in 29,3% of patients. Among the discordance outcomes, in approximately 95% we found at least 1 sperm in the TESE retrieval, while the histology report did not find any spermatozoa or found not enough compared to our evaluation; in only 5% of cases we did not find any spermatozoa or found not enough compared to what was detected in the testicular histology.

Conclusion

Based on our experience, to increase diagnostic accuracy, a larger biopsy should be sent to the histopathology laboratory; another option may be to use TESE cell suspension (the same embryologists employ for cryopreservation) for cytological evaluation of spermatogenesis.

An integrated approach for improving clinical management of non-obstructive azoospermia

BACKGROUND

Non-obstructive azoospermia is the most severe form of male infertility. A testicular biopsy is required for the diagnosis of non-obstructive azoospermia, and the causal factors for non-obstructive azoospermia remain unknown.

OBJECTIVES

To reduce the risk of multiple biopsies and identify factors that contribute to non-obstructive azoospermia, we proposed an integrated approach for the preoperative diagnosis and clinical management of non-obstructive azoospermia by applying the chromosome-spreading technique and whole-exome sequencing.

MATERIALS AND METHODS

Between July 2020 and December 2022, after ruling out definitive obstructive azoospermia and non-obstructive azoospermia patients with testicular volume < 6 mL, 20 patients with non-obstructive azoospermia who underwent preoperative testicular diagnostic biopsy using testicular sperm aspiration were subjected to retrospective analysis.

RESULTS

Microscopic examination identified four patients with sperm cells, and 16 without sperm cells. Routine pathological analysis classified one patient as normal spermatogenesis, three as hypospermatogenesis, five as maturation arrest, nine as Sertoli cell-only, and two as unable to judge. With chromosome-spreading technology using routine cell suspension samples for microscopic examination, 18 patient diagnoses were validated, and two patients without a definitive diagnosis were supplemented. Detection of the Y chromosome and a well-organized whole-exome sequencing analysis revealed potential genetic factors.

DISCUSSION AND CONCLUSION

The full use of testicular biopsy is beneficial for the diagnosis of azoospermia, as it avoids the risk of multiple biopsies. Moreover, in combination with whole-exome sequencing, clinicians can obtain more information regarding the pathogenesis of non-obstructive azoospermia, which may guide treatment.

Idiopathic secondary azoospermia occurrence in men with oligospermia over time

PURPOSE

To investigate the occurrence of idiopathic secondary azoospermia (ISA) in men with oligospermia over time and identify risk factors for ISA in this population.

METHODS

This was a retrospective cohort study conducted in a university-affiliated male infertility clinic. A total of 1056 oligospermic men (concentration < 15 million/ml (M/ml) and no azoospermia) with at least two SA done between 2000 and 2019 were included. The primary outcome was the occurrence of ISA by oligospermia severity.

RESULTS

In the entire cohort, 31 patients (2.9%) eventually became azoospermic with time. The ≤ 1 M/ml extremely severe oligospermia (ESO) group (283 patients) had significantly higher rates of ISA in each time period compared to the 1-5 M/ml severe oligospermia (SO) (310 patients) and 5-15 M/ml mild oligospermia (MO) (463 patients) groups (p < 0.05 for all comparisons), with rates of 21.1% in the ESO, 4.8% in the SO, and 0% in the MO group (p = 0.02) after 3-5 years, reaching 32% after 5 years in the ESO group compared to no cases in the other two groups (p = 0.006). Parameters shown to predict ISA were initial concentration < 1 M/ml (OR 22.12, p < 0.001) and time interval of > 3 and 5 years (OR 4.83 and 6.84, p = 0.009 and < 0.001, respectively), whereas testosterone levels were negatively associated with ISA (OR 0.88, p = 0.03).

CONCLUSIONS

Men with ≤ 1 M/ml, especially those with low testosterone levels, have a dramatically increased chance of becoming azoospermic with time. Therefore, sperm banking should be recommended in these cases. Men with a sperm concentration above 1 M/ml have low chances of becoming azoospermic, even after 3 or more years.

Clinical parameters as predictors for sperm retrieval success in azoospermia: experience from Indonesia

Background

Azoospermia is the most severe type of male infertility. This study aimed to identify useful clinical parameters to predict sperm retrieval success. This could assist clinicians in accurately diagnosing and treating patients based on the individual clinical parameters of patients.

Methods

A retrospective cohort study was performed involving 517 patients with azoospermia who underwent sperm retrieval in Jakarta, Indonesia, between January 2010 and April 2023. Clinical evaluation and scrotal ultrasound, serum follicle stimulating hormone (FSH), luteinizing hormone (LH), and testosterone levels were evaluated before surgery. Multivariate analyses were conducted to determine clinical parameters that could predict overall sperm retrieval success. Further subgroup analysis was performed to determine the factors that the diagnosis of non-obstructive azoospermia (NOA) diagnosis and sperm retrieval success among patients with NOA.

Results

A total of 2,987 infertile men attended our clinic. Men with azoospermia (n=517) who met the inclusion criteria and did not fulfil any exclusion criteria were included in the study. The overall sperm retrieval success was 47.58%. Logistic regression revealed that FSH 7.76 mIU/mL (sensitivity: 60.1%, specificity: 63.3%, p<0.001); longest testicular axis length 3.89 cm (sensitivity: 33.6%, specificity: 41.6%); and varicocele (p<0.001) were independent factors for overall sperm retrieval. The FSH cutoff of 7.45 mIU/mL (sensitivity: 31.3%, specificity: 37.7%, p<0,001); longest testicular axis length 3.85 cm (sensitivity: 76.7%, specificity: 65.4%, p<0.001); and varicocele (p<0.001) were independent factors for NOA diagnosis. Varicocele was the only clinical parameter that significantly predicted the success of sperm retrieval in patients with NOA.

Conclusions

FSH, LH, longest testicular axis, and varicocele are among the clinical parameters that are useful for predicting overall sperm retrieval success and NOA diagnosis. However, varicocele is the only clinical parameter that significantly predicts sperm retrieval success in patients with NOA. High-quality studies are required to assess the other predictors of sperm retrieval success.

How to improve the clinical outcome of round spermatid injection (ROSI) into the oocyte: Correction of epigenetic abnormalities

Background

First successful human round spermatid injection (ROSI) was conducted by Tesarik et al. in 1996 for the sole treatment of nonobstructive azoospermic men whose most advanced spermatogenic cells were elongating round spermatids. Nine offsprings from ROSI were reported between 1996 and 2000. No successful deliveries were reported for 15 years after that. Tanaka et al. reported 90 babies born after ROSI and their follow-up studies in 2015 and 2018 showed no significant differences in comparison with those born after natural conception in terms of physical and cognitive abilities. However, clinical outcomes remain low.

Method

Clinical and laboratory data of successful cases in the precursor ROSI groups and those of Tanaka et al. were reviewed.

Results

Differences were found between the two groups in terms of identification of characteristics of round spermatid and oocyte activation. Additionally, epigenetic abnormalities were identified as underlying causes for poor ROSI results, besides correct identification of round spermatid and adequate oocyte activation. Correction of epigenetic errors could lead to optimal embryonic development.

Conclusion

Correction of epigenetic abnormalities has a probability to improve the clinical outcome of ROSI.

Factors predicting successful sperm retrieval in men with nonobstructive Azoospermia: A single center perspective

Predicting successful sperm retrieval is essential in counseling infertile men with Azoospermia.

Objectives

To assess the predictors of successful sperm extraction in men with nonobstructive Azoospermia.

Patients and Methods

A retrospective study included all patients with nonobstructive Azoospermia from January 2018 to May 2019. Subdivided into two groups, group I (negative sperm retrieval) and group II (positive sperm retrieval).

Results

A total of 108 patients with a mean age of 36.8 ± 10 years were included. The rate of successful sperm retrieval was 47.2%. Group I included 57 patients (52.8%) with a mean age of 33.98 ± 6.18, and group II included 51 patients (47.2%) with a mean age of 40.04 ± 12.22 (p = 0.008). Follicular stimulating hormone (FSH) levels were significantly higher in group I (18.55 ± 13 vs. 7.97 ± 7.11; p < 0.004). Similarly, in group I, luteinizing hormone was significantly higher (11.4 ± 7.45 vs. 5.9 ± 4.4; p < 0.001). Age and FSH were the independent predictors of successful micro-TESE. Additionally, successful pregnancies were 13.7% of patients, 28.6% of which gave rise to living birth.

Conclusion

Patients' age and serum FSH are independent predictors of successful sperm retrieval for infertile men with nonobstructive Azoospermia; young patients with high FSH levels could have little chance of sperm retrieval.

Tricostatin A-treated round spermatid enhances preimplantation embryo developmental competency following round spermatid injection in mice

It has been documented that the inefficacy of round spermatid injection (ROSI) might be caused by abnormal epigenetic modifications. Therefore, this study aimed to evaluate the effect of trichostatin A (TSA) as an epigenetic modifier of preimplantation embryo development in activated ROSI oocytes. Matured oocytes were collected from superovulated female mice. Testes were placed in human tubal fluid medium and masses were then cut into small pieces to disperse spermatogenic cells. Round spermatids were treated with TSA and subsequently injected into oocytes. The expression level of the development-related genes including Oct4, Sox2, Nanog, Dnmt and Hdac transcripts were evaluated using qRT-PCR. Immunohistochemistry was performed to confirm the presence of Oct-4 protein at the blastocyst stage. There was no statistically significant difference in fertilization rate following ROSI/+TSA compared with the non-treated ROSI and intracytoplasmic sperm injection (ICSI) groups. Importantly, TSA treatment increased blastocyst formation from 38% in non-treated ROSI to 68%. The relative expression level of developmentally related genes increased and Dnmt transcripts decreased in ROSI/+TSA-derived embryos, similar to the expression levels observed in the ICSI-derived embryos. In conclusion, our results indicate that spermatid treatment with TSA prior to ROSI would increase the success rate of development to the blastocyst stage and proportion of pluripotent cells.

Fresh vs frozen testicular sperm for assisted reproductive technology in patients with non-obstructive azoospermia: A systematic review

Objective

: To review the debate about the routine use of cryopreserved testicular sperm for intracytoplasmic sperm injection (ICSI) from patients with non-obstructive azoospermia (NOA), as some authors suggest repeating sperm retrieval in such cases due to poorer ICSI results when frozen–thawed testicular sperm is used compared with fresh sperm.

Methods

: A systematic literature review was performed in August 2020 using the Medical Literature Analysis and Retrieval System Online (MEDLINE), Web of Science databases and the Excerpta Medica dataBASE (EMBASE), and we included 26 studies that were considered eligible for this systematic review.

Results

: In all, 1189 publications were screened and 26 articles were included in the systematic review. Three meta-analysis reviews were included and they all concluded that the use of fresh and frozen sperms for ICSI from patients with NOA showed comparable fertilisation and pregnancy rates.

Conclusion

: The use of frozen testicular sperm from men with NOA results in fertilisation and clinical pregnancy rates similar to those of fresh sperm. This may encourage fertility centres to use frozen testicular sperm samples, as this policy has certain advantages that would help with organising their workflow.

Abbreviations: CPR: clinical pregnancy rate; 2PN%: two pronuclei % fertilisation rate; ICSI: intracytoplasmic sperm injection; NOA: non-obstructive azoospermia; OA, obstructive azoospermia; SCO: Sertoli cell-only syndrome; (micro-)TESE: (microsurgical) testicular sperm extraction

A Catalog of Human Genes Associated With Pathozoospermia and Functional Characteristics of These Genes

Genetic causes of the global decline in male fertility are among the hot spots of scientific research in reproductive genetics. The most common way to evaluate male fertility in clinical trials is to determine semen quality. Lower semen quality is very often accompanied by subfertility or infertility, occurs in many diseases and can be caused by many factors, including genetic ones. The following forms of lowered semen quality (pathozoospermia) are known: azoospermia, oligozoospermia, asthenozoospermia, teratozoospermia, and some combined forms. To systematize information about the genetic basis of impaired spermatogenesis, we created a catalog of human genes associated with lowered semen quality (HGAPat) and analyzed their functional characteristics. The catalog comprises data on 126 human genes. Each entry of the catalog describes an association between an allelic variant of the gene and a particular form of lowered semen quality, extracted from the experimental study. Most genes included into the catalog are located on autosomes and are associated with such pathologies as non-obstructive azoospermia, oligozoospermia or asthenozoospermia. Slightly less than half of the included genes (43%) are expressed in the testes in a tissue-specific manner. Functional annotation of genes from the catalog showed that spermatogenic failure can be associated with mutations in genes that control biological processes essential for spermiogenesis (regulating DNA metabolism, cell division, formation of cellular structures, which provide cell movement) as well as with mutations in genes that control cellular responses to unfavorable conditions (stress factors, including oxidative stress and exposure to toxins).

Clinical values and advances in round spermatid injection (ROSI)

Azoospermia is defined as the complete absence of sperm cells in the ejaculate. Approximately 10-15 % of infertile men display azoospermia. Azoospermia can be subdivided into two types, obstructive azoospermia (OA) and non-obstructive azoospermia (NOA). NOA azoospermia might be the result due to primary testicular damage, secondary testicular damage, or incomplete testicular development. NOA azoospermia accounts for a considerable proportion of male infertility. A significant percentage of men with NOA azoospermia have foci of active spermatogenesis up to the stage of round spermatid. Round spermatid injection (ROSI) is a technique of assisted in-vitro fertilization (IVF) in assisted reproductive technology (ART). ROSI technique involves the injection of haploid germ cells derived from testicular biopsies into the recipient oocytes. The present study demonstrates that more participants and long-term follow-up studies are required to assess the reliability of the ROSI technique. In order to increase the success rate of the ROSI technique, round spermatids should be correctly evaluated and selected. Our study refers to the clinical values, challenges, and innovations in round spermatid injection (ROSI).

Transcriptome and DNA Methylation Profiles of Mouse Fetus and Placenta Generated by Round Spermatid Injection

Low birth efficiency and developmental abnormalities in embryos derived using round spermatid injection (ROSI) limit the clinical application of this method. Further, the underlying molecular mechanisms remain elusive and warrant further in-depth study. In this study, the embryonic day (E) 11.5 mouse fetuses and corresponding placentas derived upon using ROSI, intracytoplasmic sperm injection (ICSI), and natural in vivo fertilized (control) embryos were collected. Transcriptome and DNA methylation profiles were analyzed and compared using RNA-sequencing (RNA-seq) and whole-genome bisulfite sequencing, respectively. RNA-seq results revealed similar gene expression profiles in the ROSI, ICSI, and control fetuses and placentas. Compared with the other two groups, seven differentially expressed genes (DEGs) were identified in ROSI fetuses, and ten DEGs were identified in the corresponding placentas. However, no differences in CpG methylation were observed in fetuses and placentas from the three groups. Imprinting control region methylation and imprinted gene expression were the same between the three fetus and placenta groups. Although 49 repetitive DNA sequences (RS) were abnormally activated in ROSI fetuses, RS DNA methylation did not differ between the three groups. Interestingly, abnormal hypermethylation in promoter regions and low expression of Fggy and Rec8 were correlated with a crown-rump length less than 6 mm in one ROSI fetus. Our study demonstrates that the transcriptome and DNA methylation in ROSI-derived E11.5 mouse fetuses and placentas were comparable with those in the other two groups. However, some abnormally expressed genes in the ROSI fetus and placenta warrant further investigation to elucidate their effect on the development of ROSI-derived embryos.

Round spermatid injection into human oocytes: a systematic review and meta-analysis

Many azoospermic men do not possess mature spermatozoa at the time of surgical sperm extraction. This study is a systematic review and meta-analysis evaluating outcomes following round spermatid injection (ROSI), a technique which utilizes immature precursors of spermatozoa for fertilization. An electronic search was performed to identify relevant articles published through October 2018. Human cohort studies in English involving male patients who had round spermatids identified and used for fertilization with human oocytes were included. Fertilization rate, pregnancy rate, and resultant delivery rate were assessed following ROSI. Meta-analysis outcomes were analyzed using a random-effects model. Data were extracted from 22 studies involving 1099 couples and 4218 embryo transfers. The fertilization rate after ROSI was 38.7% (95% confidence interval [CI]: 31.5%-46.3%), while the pregnancy rate was 3.7% (95% CI: 3.2%-4.4%). The resultant delivery rate was low, with 4.3% of embryo transfers resulting in a delivery (95% CI: 2.3%-7.7%). The pregnancy rate per couple was 13.4% (95% CI: 6.8%-19.1%) and the resultant delivery rate per couple was 8.1% (95% CI: 6.1%-14.4%). ROSI has resulted in clinical pregnancies and live births, but success rates are considerably lower than those achieved with mature spermatozoa. While this technique may be a feasible alternative for men with azoospermia who decline other options, couples should be aware that the odds of a successful delivery are greatly diminished and the prognosis is relatively poor.

Testicular Mapping: A Roadmap to Sperm Retrieval in Nonobstructive Azoospermia?

Guiding a couple with nonobstructive azoospermia requires an integrated approach to care by the urologist and the reproductive endocrinologist. After informing the couple of the implications of the diagnosis, care must be taken to outline the options of parenthood. Most experts agree that sperm retrieval in men can be challenging. This article describes various options of sperm retrieval, historic and contemporary, and highlights the advantages and disadvantages of each. The authors find that using a testicular map can invariably help guide sperm retrieval and overall fertility care. The right approach is one that involves a shared decision with the couple.

Round Spermatid Injection

From a fertility perspective, men with azoospermia represent a challenging patient population. When no mature spermatozoa are obtained during a testicular sperm extraction, patients are often left with limited options, such as adoption or the use of donor sperm. However, it has been reported that round spermatids can be successfully injected into human oocytes and used as an alternative to mature spermatozoa. This technique is known as round spermatid injection (ROSI). Despite the limitations of ROSI and diminished clinical success rates, the use of round spermatids for fertilization may have potential as a treatment modality for men with azoospermia.

Intracytoplasmic sperm injection with fresh versus cryopreserved testicular sperm in azoospermic patients

Background

The purpose of this study is to compare the outcome of intracytoplasmic sperm injection (ICSI) using fresh sperm versus frozen-thawed sperm in both obstructed and non-obstructed azoospermias. This retrospective study included 159 ICSI cycles from 126 couples. In 91 obstructed azoospermia cases, 66 cycles were treated with fresh testicular sperm and 25 cycles were treated with frozen-thawed testicular samples. In 68 non-obstructed azoospermia cases, 32 cycles were treated with fresh testicular sperm and 36 cycles were treated with frozen-thawed testicular sperm, and the main measure and outcomes calculated are fertilization rate, clinical pregnancy, and live birth rate.

Results

In case of obstructed azoospermia, there were no statistically significant differences between fresh sperm and frozen-thawed testicular sperm used for ICSI regarding fertilization rate, clinical pregnancy rate, and live birth rate as shown (57%, 47%, 0.093 p value; 23.7%, 17.4%, 0.54 p value; and 11.9%, 8.7%, 0.68 p value, respectively). Non-obstructed azoospermia cases also show no significant differences in fertilization rate (37%, 36%, 0.91 p value), clinical pregnancy rate (20%, 14.3%, 0.58 p value), and live birth rate (4%, 3.6%, 0.93 p value).

Conclusion

Cryopreservation of testicular sperm is reliable if carried out before ovulation induction especially in cases with non-obstructive azoospermia

Seminiferous tubule molecular imaging for evaluation of male fertility: Seeing is believing

The proper assessment of male fertility is essential for diagnosing and treating male infertility. Currently, spermiogram and Johnsen testicular biopsy score counts are used to assess male fertility. However, spermiogram is not a suitable option for non-obstructive azoospermia patients, and Johnsen testicular biopsy scores only represent localized and not the overall spermatogenesis. Whole-mount staining was a novel method for evaluating protein expression in the tissue. Thus, we explored its application in human seminiferous tubules. Testicular biopsies from 57 azoospermia patients were categorized as obstructive azoospermia (OA), maturation arrest (MA) and Sertoli-cells only syndrome (SCOS). We performed whole-mount staining of their seminiferous tubules and evaluated the spermatogonial stem cells (SSCs), differentiated spermatogonia (SG), spermatocytes (SPC) and spermatids (SD) with their respective markers (GFRA1, CD117, SYCP3, and PNA) to assess fertility. GFRA1, CD117, SYCP3, and PNA were not expressed in SCOS patients, whereas all of them were detected in OA patients. In MA patients with arrested spermatogenesis at the SPC stage, GFRA1, CD117, and SYCP3, but not PNA were expressed in the seminiferous tubules. In MA patients with arrested spermatogenesis at the spermatogonia stage, only GFRA1 was expressed in the seminiferous tubules. These results were consistent with the Johnsen testicular biopsy score counts except for one patient, where although only Sertoli cells were indicated by the score, SSCs were also detected in the whole-mounts. Collectively, whole-mount staining could be used to analyze the inherent spermatogenesis of seminiferous tubules through staining of germ cells at different stages. It offers a more accurate and promising faster method for assessing male fertility compared with traditional biopsy screening. And it could have potential value for the clinical purpose for male fertility management.

Predictive significance of serum inhibin B on testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men

The purpose of this study was to determine the diagnostic accuracy of serum inhibin B (INHB) as a predictor of the retrieval outcome of testicular haploid gametes (spermatids and testicular spermatozoa) in nonobstructive azoospermic men. Serum hormone levels, testicular volume, and histological evaluation were performed in 403 Chinese nonobstructive azoospermic men. Testicular haploid gamete was successfully retrieved in 213 of 403 patients (52.85%). The haploid gamete group always had higher INHB levels than the non-haploid gamete group. According to the receiver operating characteristic (ROC) curve analysis, INHB was a good predictor of testicular haploid gamete retrieval outcome in all patients (sensitivity: 77.93% and specificity: 91.58%) and patients with normal follicle-stimulating hormone (FSH; sensitivity: 88.52% and specificity: 70.83%). The area under the ROC curve (AUC) of INHB was similar to that of FSH in all patients or patients with normal FSH. In patients with elevated FSH, INHB was superior to FSH in predicting the presence of haploid gamete (AUC: 0.73 vs 0.55, P < 0.05), with a sensitivity of 60.00% and a specificity of 80.28%. It concluded that serum INHB as an effective marker for spermatogenesis was a significant predictor of testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men. Especially, INHB is superior to FSH in predicting the presence of haploid gamete in the patients with elevated FSH.

Comparison of intracytoplasmic sperm injection outcome with fresh versus frozen-thawed testicular sperm in men with nonobstructive azoospermia: a systematic review and meta-analysis

PURPOSE

The purpose of the study is to explore testicular sperm cryopreservation in patients with nonobstructive azoospermia (NOA) whether affect the outcome of subsequent intracytoplasmic sperm injection (ICSI).

METHODS

A systematic review and meta-analysis was conducted by searching the MEDLINE and EMBASE databases for relevant published studies in English language (1997-2017). Studies were eligible if they included the comparison of using fresh and frozen-thawed testicular sperm followed by ICSI. Two reviewers independently performed data extraction, quality assessment and assessed the risk of bias. The overall summary risk estimated the number of events. A meta-analysis was conducted using a random effects or fixed effects model analysis according to the test of heterogeneity.

RESULTS

A total of 17 studies with 1,261 ICSI cycles were identified. Analysis of the present data showed no difference in the fertilization outcome when comparing fresh versus frozen-thawed spermatozoa (RR = 1.02, 95% CI 0.86-1.09). Similarly, no difference in CR (RR = 1.01, 95% CI 0.96-1.05), good embryo rate (RR = 1.01, 95% CI 0.95-1.09), and IR (RR = 0.93, 95% CI 0.66-1.30) was observed if the spermatozoa was fresh or frozen-thawed. Finally, no difference in CPR or LBR was noted when using fresh or frozen-thawed cycles were analyzed separately (RR = 1.03, 95% CI 0.86-1.24; RR 1.11, 95% CI 0.88-1.41, respectively).

CONCLUSIONS

In men with NOA, the ICSI outcome is not affected by whether the retrieved testicular sperm is fresh or frozen. Sperm cryopreservation ought to be considered in every surgical sperm retrieval case, which remain feasible even in patients with few testicular sperm retrieved.

Relevance of testicular histopathology on prediction of sperm retrieval rates in case of non-obstructive and obstructive azoospermia

Introduction:

The aim of our research was to establish the relevance of testicular histopathology on sperm retrieval after testicular sperm extraction in patients with non-obstructive azoospermia and in patients with obstructive azoospermia, who already underwent a previous failure testicular fine needle aspiration.

Methods:

We evaluated a total of 82 azoospermic men, underwent testicular sperm extraction, referring to the Assisted Reproductive Technology Centre of the University of Florence, Italy between January 2008 and March 2017. A general and genital physical examination, scrotal and trans-rectal ultrasound, semen analysis, hormone measurements, including follicle-stimulating hormone, luteinizing hormone and total testosterone, were collected.

Results:

Successful sperm retrieval was obtained in 36 men of total (43.9%). Successful sperm retrieval was 29.5% in non-obstructive azoospermia patients, while men with obstructive azoospermia, who, underwent a previous failure testicular fine needle aspiration, had sperm retrieval in 86% of cases. Mean luteinizing hormone was 6.55 IU/L, total testosterone 4.70 ng/mL, right testicular volume 13.7 mL and left testicular volume 13.6 mL. Mean Follicle-stimulating hormone was 13.45 IU/L in patients with negative sperm retrieval and 8.18 IU/L in men with successful sperm retrieval. According to histology, 20.7% had normal spermatogenesis, 35.3% hypospermatogenesis, 35.3% maturation arrest and 8.5% Sertoli cell-only syndrome. Successful sperm retrieval was 88.2% in patients with normal spermatogenesis, 24.1% in the maturation arrest group and 48.27% in patients with hypospermatogenesis, while negative sperm retrieval was reported in Sertoli cell-only syndrome patients. Seven cases with maturation arrest showed a successful sperm retrieval.

Conclusion:

Testicular histopathology after testicular sperm extraction offers important information on prediction of sperm retrieval and can guide the surgeon in choosing the more suitable therapeutic practice.

Y-chromosome microdeletions in nonobstructive azoospermia and severe oligozoospermia

The aim of the present work was to present the outcomes of the patients with Y-chromosome microdeletions treated by intracytoplasmic sperm injection (ICSI), either using fresh (TESE) or frozen-thawed (TESE-C) testicular sperm and ejaculated sperm (EJAC). The originality of this work resides in the comparisons between the different types of Y-microdeletions (AZFa, AZFb, and AZFc) and treatments, with detailed demographic, stimulation, embryological, clinical, and newborn (NB) outcomes. Of 125 patients with Y-microdeletions, 33 patients presented severe oligozoospermia (18 performed ICSI with ejaculated sperm) and 92 secretory azoospermia (65 went for TESE with 40 having successful sperm retrieval and performed ICSI). There were 51 TESE treatment cycles and 43 TESE-C treatment cycles, with a birth of 19 NB (2 in AZFa/TESE-C, 12 in AZFc/TESE, and 5 in AZFc/TESE-C). Of the 29 EJAC cycles, there was a birth of 8 NB (in AZFc). In TESE and EJAC cycles, there were no significant differences in embryological and clinical parameters. In TESE-C cycles, there was a significant lower oocyte maturity rate, embryo cleavage rate and mean number of embryos transferred in AZFb, and a higher mean number of oocytes and lower fertilization rate in AZFc. In conclusion, although patients with AZFc microdeletions presented a high testicular sperm recovery rate and acceptable clinical outcomes, cases with AZFa and AZFb microdeletions presented a poor prognosis. Due to the reported heredity of microdeletions, patients should be informed about the infertile consequences on NB and the possibility of using preimplantation genetic diagnosis for female sex selection.

Corino de Andrade disease: mechanisms and impact on reproduction

Familial amyloid polyneuropathy was first described by Corino de Andrade in 1952 in Northern Portugal. It is a fatal autosomal dominant neurodegenerative disorder characterized by a progression of neurologic symptoms, beginning early in the reproductive life. The Transthyretin gene mutation originates a mutated protein that precipitates in the connective tissue as amyloid deposits. This disease is presently named Transthyretin-related hereditary amyloidosis. We performed an extensive review on this disease based on searches in Medical databases and in paper references. In this review, we briefly summarize the epidemiology and the mechanisms involved on amyloid deposition; we detailed how to evaluate the mechanisms implicated on the development of the major signs and symptoms associated with reproductive dysfunction; and we discuss the mechanisms involved in secondary sexual dysfunction after psychological treatments. Treatment of the disease is directed towards relieving specific symptoms in association with liver transplant, and molecular and genetic therapeutics. Although the current clinical trials indicate symptoms relief, no data on the reproductive function was reported. Thus, preimplantation genetic diagnosis is presently the only available technique that eradicates the disease as it avoids the birth of new patients.

Factors influencing sperm retrieval following testicular sperm extraction in nonobstructive azoospermia patients

Objective

Azoospermia owing to testicular disorders is the most severe manifestation of male infertility. The main concern for patients with nonobstructive azoospermia (NOA) is the probability of successful sperm retrieval following testicular sperm extraction (TESE). Therefore, the goal of this study was to determine predictive factors correlated with sperm retrieval.

Methods

We assessed the testicular histopathological patterns, the choice of TESE surgical procedure, hormone levels, and chromosomal abnormalities in patients with NOA (n=170). The histopathology specimens were analyzed based on the histopathological patterns of hypospermatogenesis, maturation arrest, and Sertoli cell-only syndrome.

Results

The mean rate of sperm retrieval was 48.8%. The rate of sperm retrieval was significantly higher in the hypospermatogenesis group than in the other groups (p<0.001). There was a positive correlation between micro-TESE (vs. conventional TESE) and the sperm retrieval rate (odds ratio, 8.077; p<0.01). A logistic regression model demonstrated that high levels of follicle-stimulating hormone (FSH) and small testicular volume were significantly associated with lower chances of successful sperm retrieval.

Conclusion

Some parameters, including testicular histopathology patterns, FSH levels, testicular volume, and method of TESE surgery, may be able to predict the chances of obtaining spermatozoa in patients with NOA. However, despite the efficiency of some predictive models, the hope of retrieving any functioning spermatozoa may be sufficient to disregard predictive factors of the success of intracytoplasmic sperm injection in these patients.

DNA methylation imprinting errors in spermatogenic cells from maturation arrest azoospermic patients

Imprinting errors have been described in spermatozoa from infertile patients with oligozoospermia and azoospermia. However, little is known about methylation of imprinted genes in other spermatogenic cells from azoospermic patients. Therefore, we aimed to evaluate the methylation status of single CpGs located in the differentially methylated regions (DMRs) of two imprinted genes, one paternally (H19) and one maternally (MEST) methylated, in primary spermatocytes of azoospermic patients presenting complete (MAc, n = 7) and incomplete (MAi, n = 8) maturation arrest, as well as in other spermatogenic cells from MAi patients that presented focus of complete spermatogenesis in some seminiferous tubules. We observed H19 imprinting errors in primary spermatocytes from one MAi patient and MEST imprinting errors in one MAi and two MAc patients. Additionally, H19 imprinting errors were observed in elongated spermatids/spermatozoa from one MAi patient. Nevertheless, no statistical differences were found for H19 and MEST global methylation levels (percentage of methylated and unmethylated CpGs, respectively) between patients with complete and incomplete MA and also between MA groups and a control group. These results provide further evidence that imprinting errors occur in spermatogenic cells from patients presenting impaired spermatogenesis, as we and others have previously described in ejaculated and testicular spermatozoa. As paternal imprinting errors can be transmitted to the embryo by the sperm cell, they can provide a possible explanation for poor embryo development and/or low pregnancy rates as correct expression of imprinted genes is crucial for embryo and placental development and function. Therefore, in cases with male factor infertility where unsuccessful in vitro fertilization (IVF) treatments are recurrent, analysis of imprinting marks in spermatozoa might be a useful diagnostic tool.

Successful fertilization and embryo development after spermatid injection: A hope for nonobstructive azoospermic patients

Spermatids are the earliest male germ cells with haploid set of chromosomes. Spermatid injection was introduced in human assisted reproduction for the treatment of men with non-obstructive azoospermia. Spermatozoa can be recovered in half of patients with nonobstructive azoospermia. The use of spermatids for intracytoplasmic injection (ICSI) has been proposed for cases in which no spermatozoa can be retrieved. However, there are low pregnancy rates following ICSI using round spermatids from men with no elongated spermatids or spermatozoa in their testes. The in vitro culture of immature germ cells has been proposed as a means to improve this poor outcome. Oocyte activation rarely occurs when injected with a spermatid. Therefore, spermatid injection requires use of calcium ionophores for oocyte activation which is otherwise carried out by PLC zeta from mature sperms. This is the only option available for the nonobstructive azoospermic patients to have their own biological child.

How successful is TESE-ICSI in couples with non-obstructive azoospermia?

STUDY QUESTION

What are the chances of a couple with infertility due to non-obstructive azoospermia (NOA) having their genetically own child by testicular sperm extraction combined with ICSI (TESE-ICSI)?

SUMMARY ANSWER

Candidate TESE-ICSI patients with NOA should be counselled that, when followed-up longitudinally, only a minority (13.4%) of men embarking for TESE eventually become a biological father.

WHAT IS KNOWN ALREADY

Data available in the literature are only fragmentary because they report either on sperm retrieval rates after TESE or on the outcome of ICSI once testicular spermatozoa has been obtained, mostly in a selected subpopulation. Unfortunately, reliable data to counsel men with NOA on their chance to become a biological father are still lacking.

STUDY DESIGN, SIZE, DURATION

This is a retrospective cohort study performed in the Centre for Reproductive Medicine, University Hospital of Brussel, approved by the institutional review board of the hospital.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

We identified all patients with NOA, based on histology, who had their first testicular biopsy between 1994 and 2009. Patients were followed longitudinally during consecutive ICSI cycles with testicular sperm. The primary outcome measure was live birth delivery. The cumulative live birth delivery rate was calculated, based only on ICSI cycles with testicular sperm (fresh and/or frozen) available for injection. When patients delivered after transfer of supernumerary frozen embryos, this delivery was tallied up to the (unsuccessful) original fresh ICSI cycle. The sperm retrieval rate and pregnancy rate were secondary outcome measures.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 714 men with NOA, 40.5% had successful sperm retrieval at their first TESE. In total, 261 couples had 444 ICSI cycles and 48 frozen embryo transfer cycles, leading to 129 pregnancies and 96 live birth deliveries. Crude and expected cumulative delivery rates after six ICSI cycles were 37 and 78%.

LIMITATIONS AND REASON FOR CAUTION

A retrospective cohort study design was the only way to study the cumulative delivery rate after TESE-ICSI in couples with NOA. Intrinsic limitations are related to the observational study design.

WIDER IMPLICATION OF THE FINDING

TESE-ICSI is a breakthrough in the treatment of infertility due to NOA, with almost 4 out of 10 (37%) couples having ICSI obtaining a delivery. However, unselected candidate NOA patients should be counselled, before undergoing TESE, that only one out of seven men (13.4%) eventually father their genetically own child.

STUDY FUNDING AND COMPETING INTERESTS

None declared.

Morphological characterization and conservation of bovine spermatogenic cells by refrigeration at 4°C and freezing using different cryoprotective molecules

The objectives of this study were study a practical method to characterize bovine spermatogenic cells and test the efficiency cells conservation by refrigeration at 4°C and cryopreservation in different solutions using two cooling curves. Cellular identification was performing by analysis of shape, size and morphology, associated with nucleus positioning and nuclear-cytoplasm ratio (NCR). Cellular samples were kept at 4°C for a period of 96 h in refrigeration solution and every 24h plasma membrane and DNA integrity were evaluated. Cryopreservation of cells was carried out using solutions containing 10% Dimethyl sulfoxide, 5% Dimethylformamide, 7% Glycerol and 7% Ethylene glycol, using a controlled and non-controlled cooling curve. Results of cellular characterization demonstrated that spermatocytes II presented a cylindrical shape, NCR of 1:1.5 and diameter ranging from 14.5 to 17.5 μm. Round spermatids presented diameter ranging from 7.6 to 13.4 μm, acrosomal cap and NCR of 1:2. Elongation and elongated spermatids showed to marked divergence in shape. There was a daily significant loss of viability of cooled cells until third day of storage, however they presented 72.77±5.16% viability after 4 days of storage at 4°C. There was no difference among the cryoprotectant solutions and cooling curves. In conclusion we demonstrated that association of microscopes and staining was a practical method to identify bovine spermatogenic cells. Furthermore, refrigeration at 4°C is an important strategy to preserve over 70% of viable cells after 4 days and cryopreservation, regardless of cryoprotectant solution or cooling curve used, can maintain over 50% of cells viable.

Impact of fresh versus cryopreserved testicular sperm upon intracytoplasmic sperm injection pregnancy outcomes in men with azoospermia due to spermatogenic dysfunction: a meta-analysis

OBJECTIVE

To determine if clinical pregnancy rates and fertilization rates with the use of cryopreserved sperm for intracytoplasmic sperm injection (ICSI) in patients with azoospermia due to spermatogenic dysfunction (i.e., nonobstructive azoospermia) are similar to those with fresh sperm.

DESIGN

Systematic review and meta-analysis.

SETTING

Academic medical center.

PATIENT(S)

Azoospermic men secondary to spermatogenic dysfunction.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate, fertilization rate.

RESULT(S)

Eleven studies met criteria for the outcome of clinical pregnancy rate. Seventy-nine (28.7%) of 275 intracytoplasmic sperm injection cycles using fresh testicular sperm resulted in a clinical pregnancy, compared with 84 (28.1%) of 299 intracytoplasmic sperm injection cycles using cryopreserved sperm (relative risk [RR] 1.00, 95% confidence interval [CI] 0.75-1.33). Ten studies met criteria for the outcome of fertilization rate. A total of 1,422 (52.9%) of 2,687 oocytes injected with fresh testicular sperm were fertilized, compared with 1,490 (54.0%) of 2,757 oocytes injected with cryopreserved sperm (RR 0.97, 95% CI 0.92-1.02).

CONCLUSION(S)

In men with azoospermia due to spermatogenic dysfunction, there is no statistical difference between the use of fresh versus cryopreserved-thawed testicular sperm when assessing clinical pregnancy or fertilization rates in couples undergoing ICSI.

Embryological, clinical and ultrastructural study of human oocytes presenting indented zona pellucida

Human oocyte dysmorphisms attain a large proportion of retrieved oocytes from assisted reproductive technology (ART) treatment cycles. Extracytoplasmic defects involve abnormal morphology of the zona pellucida (ZP), perivitelline space and first polar body. The aim of the present study was to describe a novel dysmorphism affecting the ZP, indented ZP. We also evaluated the clinical, embryological and ultrastructural features of these cases. We evaluated all ART treatment cycles during 7 consecutive years and found 13 treatment cycles (six patients) with all oocytes presenting an indented ZP. In addition, these oocytes presented total or partial absence of the perivitelline space, absence of resistance to ZP and oolemma penetration during microinjection, and low ooplasm viscosity during aspiration. This novel described dysmorphism was recurrent and attained all oocytes in three cases that had more than one treatment cycle. When compared with controls, data showed significant low oocyte maturity (42% versus 81.6%) and high cycle cancellation (30.8% versus 8.5%) rates, normal degeneration (3.4% versus 6.3%) and fertilization rates (69% versus 69.5%), and low pregnancy (15.4% versus 33.3%) and live-birth delivery (7.7% versus 27.7%) rates per cycle. Ultrastructure analysis revealed a zona pellucida structure with large empty electrolucent regions, an outer ZP layer with an indented surface with protuberances and a thick inner ZP that obliterated the perivitelline space. There was evidence of exocytosis of ZP material by the oocyte. In conclusion, oocytes with this novel described dysmorphism (indented ZP) are associated with low maturity, pregnancy and live-birth delivery rates.

Aberrant methylation of the TDMR of the GTF2A1L promoter does not affect fertilisation rates via TESE in patients with hypospermatogenesis

Increasing evidence shows a relationship between epigenetic regulation and male infertility. The GTF2A1L gene promoter contains the DNA methylation site of a tissue-specific differentially methylated region (TDMR). Eighty-six patients with non-obstructive azoospermia were assessed for the DNA methylation state of CpG islands in the GTF2A1L promoter using testicular genomic DNA. Based on histological criteria, 26 of the 86 patients had normal spermatogenesis (controls), 17 had hypospermatogenesis and 26 had a Sertoli cell-only phenotype or tubular sclerosis. GTF2A1L TDMR methylation was significantly lower in testes DNA from control samples than from hypospermatogenic samples (P=0.029). Patients with hypospermatogenesis were divided into two subgroups: high DNA methylation (HM, n=5) and low DNA methylation (LM, n=12). The GTF2A1L TDMR methylation rate differed significantly between the HM and LM groups (P=0.0019), and GTF2A1L expression was significantly higher among the LM than in the HM patients (P=0.023). High TDMR methylation was correlated with low GTF2A1L gene expression levels. Both groups demonstrated relatively good outcomes with respect to sperm retrieval, fertilisation, pregnancy and childbirth rates. We observed that aberrant GTF2A1L gene expression was not correlated with fertilisation rates. The testicular sperm extraction (TESE) technique may be used to overcome male infertility due to aberrant TDMR methylation.

Expression of stem cell markers: OCT4, KIT, ITGA6, and ITGB1 in the male germinal epithelium

Efforts have been made for the isolation and characterization of human stem spermatogonia (SG) which would be of major interest for fertility preservation in oncologic patients. We evaluated the expression of mammalian SG stem cell markers, KIT, OCT4, integrin alpha 6 (ITGA6), and integrin beta 1 (ITGB1) as possible indicators for the isolation of those cells in humans. Two different types of SG were individually isolated by micromanipulation from testicular biopsies of men with conserved spermatogenesis. Expression of mRNA showed the absence of KIT and ITGB1 markers in SG. By immunocytochemistry (IC), protein expression for KIT and integrins revealed two types of SG populations, negative (type-1) and positive (type-2). By immunohistochemistry (IH), protein expression for KIT and ITGB1 also revealed two kinds of SG populations, negative (SG A-dark) and positive (SG A-pale). Results suggest that in humans it may be possible to obtain pure populations of stem SG by using negative KIT((-))/ITGB1((-)) sorting.

Predictive factors of successful sperm retrieval in azoospermia

INTRODUCTION

Testicular sperm extraction with intracytoplasmic sperm injection is the standard treatment for azoospermia. The objective of this study is to identify predictive factors of successful sperm retrieval.

MATERIALS AND METHODS

Between June 2003 and May 2011, we tried testicular sperm extraction (TESE) in 74 azoospermic patients in the Reproductive Medicine Unit of Son Espases Hospital (Palma de Mallorca). Serum follicle stimulating hormone (FSH) and inhibin B levels, testicular histology, genetic study, presence or not of cryptozoospermia and testicular volume were examined.

RESULTS

Spermatozoa were successfully recovered in 47.2% of the total patients, in 36% of non-obstructive azoospermic patients and in 100% of obstructive azoospermic patients. Low inhibin B and high FSH were correlated to sperm retrieval failure. The cutoff points were determined using ROC curves that were 67 pg/mL for inhibin B and 12.2 mUI/mL for FSH. Spermatozoa were not successfully retrieved in any patient with Y microdeletions in AZFa,b regions. Spermatozoa were successfully retrieved in 100% of the patients with CFTR mutations. The highest sperm retrieval rate was for hypospermatogenesis, followed by maturation arrest and Sertoli-cell-only. Spermatozoa were successfully retrieved in all cryptozoospermic patients. Although using a non-significant test, there seems to be a correlation between higher testicular volume and a higher probability of successful sperm retrieval.

CONCLUSIONS

Except for Y microdeletions in AZFa,b regions, there is no predictive factor of testicular sperm retrieval to rule out a patient for TESE. Lower inhibin B is more related to sperm retrieval failure than higher FSH. Sperm retrieval is possible for all cases of CFTR mutations but in any case of microdeletion Y in AZFa,b. The lack of germ cells is correlated with a high probability of sperm retrieval failure. The presence of cryptozoospermia is correlated with a high probability of sperm retrieval success. We do not find a statistically significant relation between testicular volume and successful sperm retrieval.

Caspase signalling pathways in human spermatogenesis

PURPOSE

Little is known about the apoptotic mechanisms involved in abnormal spermatogenesis. In order to describe the significance of apoptosis in azoospermia, testicular tissue from abnormal spermatogenesis was analysed.

METHODS

Testicular treatment biopsies were obtained from 27 men. Five presented oligozoospermia, 9 obstructive azoospermia (4 congenital bilateral absence of the vas deferens; 5 secondary azoospermia) and 13 non-obstructive azoospermia (5 hypospermatogenis; 3 maturation arrest; 5 Sertoli-cell-only syndrome). Immunohistochemical staining was performed for active caspases-3, -8 and -9. The presence of active caspases in Sertoli cells and germ cells was analyzed using stereological tools.

RESULTS

Increased active caspase-3 was found in Sertoli-cell-only syndrome. No significant differences were found in maturation arrest. In hypospermatogenesis, primary spermatocytes were the germ cells with higher active caspases. Oligozoospermia and secondary obstruction showed significant differences among germ cells for the presence of all active caspases. In oligozoospermia, spermatogonia presented significant increased active caspase-9 in relation to active caspase-8. In primary obstruction and hypospermatogenesis, germ cells presented significant increased active caspases-3 and -9.

CONCLUSIONS

Results suggest that increased active caspase-3 might be involved in Sertoli-cell-only syndrome etiology. In cases of hypospermatogenesis, intrinsic lesions at the meiotic stage seem to be related to the pathology. In secondary obstruction apoptosis is suggested to be initiated due to extrinsic and intrinsic lesions, whereas in primary obstruction only the intrinsic apoptotic pathway seems to be present. Finally, in oligozoospermic patients spermatogonia death by mitochondrial damage additionally to meiosis malfunctioning, might be on the origin of the decreased sperm output.

Intracytoplasmic spermatid injection and in vitro maturation: fact or fiction?

Intracytoplasmic injection with testicular spermatozoa has become a routine treatment in fertility clinics. Spermatozoa can be recovered in half of patients with nonobstructive azoospermia. The use of immature germ cells for intracytoplasmic injection has been proposed for cases in which no spermatozoa can be retrieved. However, there are low pregnancy rates following intracytoplasmic injection using round spermatids from men with no elongated spermatids or spermatozoa in their testes. The in vitro culture of immature germ cells to more mature stages has been proposed as a means to improve this poor outcome. Several years after the introduction of intracytoplasmic injection with elongating and round spermatids, uncertainty remains as to whether this approach can be considered a safe treatment option. This review outlines the clinical and scientific data regarding intracytoplasmic injection using immature germ cells and in vitro matured germ cells.

Effect of polyvinylpyrrolidone on sperm function and early embryonic development following intracytoplasmic sperm injection in human assisted reproduction

The objective here was to review the effects of polyvinylpyrrolidone (PVP) upon sperm function and embryonic development in humans. PVP has been used successfully in intracytoplasmic sperm injection (ICSI) to facilitate the handling and immobilization of sperm for both domestic animals and humans. In our previous reports, PVP solution exists locally in embryos injected during the early developmental period, and also exerts influence over the developmental capacity of such embryos. In other reports, PVP causes significant damage to sperm membranes that can be detected by transmission electron microscopy, and has been associated with chromosomal abnormalities in pregnancy derived from ICSI embryos. In some Japanese clinics, PVP-free media has been used for sperm immobilization in order to optimise safety. Consequently, it is strongly suggested that the success rate of fertilization and clinical pregnancy could be improved by using PVP-free solution for human ICSI. In conclusion, our interpretation of the available data is to perform ICSI without PVP or select a lower concentration of PVP solution in order to reduce safety for pregnancy and children born via ICSI.

Identification of androgen receptor variants in testis from humans and other vertebrates

The androgen receptor (AR) is a ligand-activated transcription factor member of the nuclear receptor superfamily. The existence of alternatively spliced variants is well recognised for several members of this superfamily, most of them having functional importance. For example, several testicular oestrogen receptor variants have been suggested to play a role in the regulation of spermatogenesis. However, information on AR variants is mostly related to cancer and androgen insensitivity syndrome (AIS) cases. The objective of this study was to investigate the expression of AR variants in the testis from humans and other vertebrates. Four AR variants [ARΔ2(Stop) , ARΔ2(23Stop) , ARΔ3 and ARΔ4(120)] were identified in human testis. ARΔ2(Stop) and ARΔ3, with exon 2 or 3 deleted, respectively, were also expressed in human liver, lung, kidney and heart. In addition, ARΔ2(Stop) was expressed in rat and gilthead seabream testis, while an ARΔ3 was detected in African clawed frog testis. This is the first report revealing the existence of AR variants in the testis of evolutionarily distant vertebrate species and in nonpathological tissues. These data suggest the functional importance of these novel AR forms and demonstrate a complexity in AR signalling that is not exclusive of pathological conditions.

Testicular histopathology as a predictor of a positive sperm retrieval in men with non-obstructive azoospermia

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The management of patients with non-obstructive azoospermia (NOA) involves testicular sperm extraction (TESE or microdissection TESE) combined with intracytoplasmic sperm injection (ICSI). Sperm retrieval is successful in up to 50% of men with NOA; however, there is no single clinical finding or investigation that can accurately predict a positive outcome. Several studies have concluded that testicular biopsy is the best predictor of a successful TESE. The present study shows that the strongest predictor of the success of TESE is when tubules with mature spermatozoa (Johnsen score ≥8) are found in the histopathology specimen, irrespective of the overall state of spermatogenesis. The findings suggest that a lower limit threshold value of 2% of tubules with spermatogenesis in the histopathology specimen will result in a positive sperm retrieval. However, it is not practical to perform a diagnostic biopsy before TESE because this would mean that patients undergo two surgeries, which adds to the cost and increases the complications. The diagnostic biopsy is best coupled with an initial TESE before starting the ICSI cycle. Based on the findings of the histopathology specimen, patients may be then offered a repeat TESE if more sperm is needed on the day of ovum pick-up and ICSI. Also, if the initial TESE was negative, the biopsy result will help in the decision to offer a repeat TESE. This regimen is more cost-effective because the ICSI cycle will be started only if adequate sperm is retrieved.

OBJECTIVE

To assess whether testicular histopathology can predict the outcome of testicular sperm extraction (TESE) in men with non-obstructive azoospermia (NOA) and therefore the role of preoperative diagnostic testis biopsy.

PATIENTS AND METHODS

The study comprised a retrospective analysis of 388 patients with azoospermia who were referred from 2005 to 2010. Information collected included a clinical history and an examination including age and testicular size, serum follicle-stimulating hormone, two semen analyses and testicular histology collected at the time of surgical sperm retrieval (TESE or microdissection TESE).

RESULTS

In total, 388 patients with a mean (range) age of 37 (18-66) years were included in the present study. Based on the history, clinical and laboratory findings, 112 patients had obstructive azoospermia and 276 patients had NOA. All patients in the obstructed group had a positive sperm retrieval. The sperm retrieval rate for the NOA group was 50%. An analysis of the results showed that the best predictor of a positive sperm retrieval was when tubules with mature spermatozoa were seen at biopsy, irrespective of the overall state of spermatogenesis (P < 0.001).

CONCLUSIONS

The presence of tubules with spermatazoa on biospy is the best predictor of a positive surgical sperm retrieval in patients with NOA. The diagnostic biopsy is best coupled with an initial TESE before starting the intracytoplasmic sperm injection (ICSI) cycle. Based on the findings of the histopathology specimen, patients may be offered a repeat TESE if more sperm is needed on the day of ovum pick-up and ICSI, or a redo TESE if the initial TESE was negative.

Cryopreservation of human testicular diploid germ cell suspensions

For patients with threatened fertility, preservation of it is a major concern. Although promising results have been obtained in animal models using testicular germ cell suspensions, in humans, it is crucial to first develop an efficient method of cryopreservation to be able to apply to transplantation. Thus, four reliable and available cryopreservation techniques in any fertility centre were tested to cryopreserve an enriched fraction of diploid germ cells isolated from human testicular biopsies. The protocols were evaluated based on cell viability, and the results showed significant differences between the four methods. The semen and tissue cryopreservation methods appeared to be inadequate for diploid germ cell suspensions, and programmed slow freezing gave significantly lower results than open pulled straw vitrification; the latter was found to be the protocol that best preserved cell viability. The vitrification of isolated human diploid germ cells is innovative and constitutes valuable information for cryopreservation in cases of transplants or in vitro maturation.

Expression analysis of MLH3, MLH1, and MSH4 in maturation arrest

The expression of DNA mismatch repair (DMMR) genes in patients with maturation arrest (MA) was analyzed. Samples were subjected to mutL homolog 3 (MLH3) mutation analysis by denaturing high-performance liquid chromatography/sequencing and quantification of MMR expression in testicular tissue by real-time polymerase chain reaction (PCR). Microsatellite instability assays were negative. Two missense and 1 intronic mutations were found. The missense mutation 2531C/T (P844 L), predicted to affect MLH3 function, was found in 3 MA cases in association with the intronic variant IVS9 + 66G/A. Relative messenger RNA (mRNA) quantification identified 2 patients who overexpressed MLH3, 1 of them also overexpressing mutL homolog 1 (MLH1). The latter also presented the 2531C/T-IVS9 + 66G/A mutation. In conclusion, we suggest that a predominance of MLH3 expression might favor the MLH1/MLH3 complex which then would compete with the MLH1/PMS2 complexes. This could convey disruption of the relative stoichiometry between MLH1/MLH3 and MLH1/PMS2 complexes, thus causing meiosis failure, as MLH1/PMS2 complexes are supposed to replace MLH1/MLH3 during diplonema.

Regucalcin is broadly expressed in male reproductive tissues and is a new androgen-target gene in mammalian testis

Regucalcin (RGN) is a calcium (Ca2+)-binding protein which regulates intracellular Ca2+homeostasis by modulating the activity of enzymes regulating Ca2+concentration and enhancing Ca2+-pumping activity. Several studies have described the pivotal role of proper Ca2+homeostasis regulation to spermatogenesis and male fertility. Recently,RGNwas identified as a sex steroid-regulated gene in prostate and breast; however, a possible role of RGN in spermatogenesis has not been examined. In this study, the expression and localization of RGN in rat and human testis, and other rat reproductive tissues was analyzed. Moreover, we studied whether RGN protein was present in seminiferous tubule fluid (STF). Finally, we examined the effect of 5α-dihydrotestosterone (DHT) on the expression ofRgnmRNA in rat seminiferous tubules (SeT) culturedex vivo. The results presented in this study show that RGN is expressed in Leydig and Sertoli cells, as well as in all types of germ cells of both rat and human testis. RGN is also expressed in rat prostate, epididymis, and seminal vesicles. Moreover, RGN protein is present in rat STF. The results also demonstrate thatRgnexpression is age dependent in rat testis, and is upregulated by the non-aromatizable androgen DHT in rat SeT culturedex vivo. Taken together, these findings indicate thatRgnis a novel androgen-target gene in rat testis and that it may have a role in male reproductive function, particularly in the control of spermatogenesis.