Utility of micro-TESE in the most severe cases of non-obstructive azoospermia

Future prospects for the advancement of treatment of men with NOA: focus on gene editing, artificial sperm, stem cells, and use of imaging

Nonobstructive azoospermia (NOA) affects about 60% of men with azoospermia, representing a severe form of male infertility. The current approach to manage NOA primarily involves testicular sperm retrieval methods such as conventional testicular sperm extraction (c-TESE) and microdissection testicular sperm extraction (micro-TESE). While combining testicular sperm retrieval with intracytoplasmic sperm injection (ICSI) offers hope for patients, the overall sperm retrieval rate (SRR) stands at around 50%. In cases where micro-TESE fails to retrieve sperm, limited options, like donor sperm or adoption, can be problematic in certain cultural contexts. This paper delves into prospective treatments for NOA management. Gene editing technologies, particularly clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) protein 9 (CRISPR/Cas9), hold potential for correcting genetic mutations underlying testicular dysfunction. However, these technologies face challenges due to their complexity, potential off-target effects, ethical concerns, and affordability. This calls for research to address key challenges associated with NOA management within the clinical settings. This also necessitate ongoing research essential for developing more sensitive diagnostic tests, validating novel treatments, and customizing current treatment strategies for individual patients. This review concluded that the future of NOA management may entail a combination of these treatment options, tailored to each patient's unique circumstances, providing a comprehensive approach to address NOA challenges.

Effectiveness of, and Satisfaction with, a Microsurgical Testicular Sperm Extraction Knowledge and Skills Masterclass for a World-Wide Audience

PURPOSE

This is the first study to assess the impact of an online microsurgical testicular sperm extraction (mTESE) masterclass. We: 1) describe the masterclass's scientific content; 2) appraise the participants' acquisition of knowledge; 3) gauge whether the extent of improvement of the participants' knowledge/skills was influenced by demographic/professional attributes; and 4) evaluate the participants' satisfaction.

MATERIALS AND METHODS

This masterclass comprised five didactic lectures followed by 4 case discussions. Online surveys assessed the above objectives using a baseline questionnaire including demographics and past mTESE experience/training, a 24-question pre- and post-quiz, and a satisfaction questionnaire.

RESULTS

Participants were between 20-70 years old, with 80.37% males, mainly from Asia, Africa, and Europe, from clinical backgrounds (69.3%), and in public practice (64.4%). Half the sample reported no past mTESE training and very low skills, ≈60% wanted considerably more training, and 50% felt that good training was not readily available. Satisfaction was 98% to >99%. Pre- and post-quiz comparisons confirmed remarkable improvements in knowledge/skills, exhibiting five striking characteristics. Improvements were a) Broad i.e., across 19 of the 24 mTESE questions; b) Deep, of magnitude, as pre-/post-quiz scores improved from mean 13.71±4.13 to 17.06±4.73; c) Highly significant, consistently with p-values <0.001; d) Inclusive i.e., all participants enhanced their mTESE knowledge/skills regardless of demographic/professional attributes; and, e) Differential, e.g., non-clinical/clinical participants improved, but the former improved relatively significantly more, those with ≤5-year experience improved significantly more than those with >5-year, those in public practice significantly more than private practice participants, and those with lower self-rating in performing mTESE significantly more than those with higher self-rating.

CONCLUSIONS

The masterclass was successful with very high satisfaction levels, and markedly improved mTESE knowledge/skills among the participants. Global Andrology Forum's model can be adopted by organizations with similar goals. Future research needs to evaluate such training to develop a practically non-existent evidence base.

Feasibility of high-frequency ultrasound for seminiferous tubule assessment and correlation of B-mode imaging with pathological findings in the testis in azoospermia

PURPOSE

To determine the feasibility of high-frequency ultrasound (HFUS) for assessing seminiferous tubules and to understand high-resolution B-mode images of the testes in cases of azoospermia.

METHODS

We verified how the histopathological images of testicular biopsy specimens can be observed using HFUS images and measurement analysis of seminiferous tubules was performed to 28 testes of 14 cases with azoospermia who underwent preoperative ultrasound and microdissection testicular sperm extraction (micro-TESE). The population consisted of obstructive azoospermia (OA) and non-obstructive azoospermia (NOA), including Sertoli cell-only syndrome (SCOS), and the other pathologies. Statistical verification of differences in seminiferous tubule diameters among preoperative ultrasound examination, ultrasound examination of pathological specimens, and histopathological specimens. We also examined the imagingpathology correlation via a case series presentation, aiming to identify imaging markers of testicular pathology and determine the possibility of predicting each condition.

RESULTS

A comparison between HFUS images and histopathology from the same biopsy specimens suggested that ultrasonography could be seen as stereoscopic images due to its significantly greater slice thickness. The diameters of tubules were generally larger in pathological tissues as compared to ultrasonographic findings in OA and SCOS, but not in the other conditions. Comparisons provided insights into the predictability of SCOS and revealed imaging findings such as gaps between tubules and decreased diameter reflective of testicular damage.

CONCLUSION

Seminiferous tubules can be observed however the diameter of seminiferous tubules varies in imaging and histopathology depending on the pathology. Imaging findings that reflect testicular damage and the predictability of SCOS were revealed in this study, but further verification is required.

Microdissection testicular sperm extraction outcomes in azoospermic patients with bilateral orchidopexy

BACKGROUND

Cryptorchidism is considered to be one of the most common causes of non-obstructive azoospermia. There are several surgical techniques to retrieve sperm in these patients. Microdissection testicular sperm extraction (m-TESE) is a recent sperm retrieval technique which is considered to be a safe, non-blind, and feasible method.

OBJECTIVES

This study aimed to investigate sperm retrieval rate (SRR) by the mTESE method in patients who have undergone orchidopexy due to bilateral cryptorchidism.

MATERIALS AND METHODS

In this retrospective study, 56 ex-cryptorchid patients, who underwent mTESE due to post orchidopexy azoospermia, were included. Patients with hypogonadotropic hypogonadism, Klinefelter syndrome, azoospermia factors (AZF) microdeletion, or chromosomal translocation were excluded from the study. Data were obtained from medical files.

RESULTS

SRR in this study was 46%. Patients were divided into two groups of negative (n = 30) and positive (n = 26) based on the sperm extraction outcomes. There was no statistically significant difference between two groups regarding the mean age at mTESE, mean age at orchidopexy, testicular size, and serum testosterone concentration. However, testicular location, histological patterns, FSH, and LH level showed to have statistically significant relation with sperm retrieval results. But, according to our logistic regression, none of the included variable in the model including FSH, LH, histopathology, and testis location have a significant effect on the presence of the sperm.

DISCUSSION

In the present study, SRR was significantly higher in patients with scrotal testis and low level of FSH and LH.

CONCLUSIONS

Performing mTESE could be recommended in ex-cryptorchid patients with post orchidopexy NOA. Preoperative testicular biopsy seems to be unnecessary while clinical criteria can perfectly define NOA.

Identification of biomarkers associated with macrophage infiltration in non-obstructive azoospermia using single-cell transcriptomic and microarray data

Background

Non-obstructive azoospermia (NOA) is a common clinical cause of male infertility. Research suggests that macrophages are linked to testicular function; however, their involvement in NOA remains unknown.

Methods

To evaluate the importance of macrophages infiltration in NOA and identify the macrophage-related biomarkers, the gene-expression microarray data GSE45885 and the single-cell transcriptomic data GSE149512 were utilized from the Gene Expression Omnibus (GEO). A single-sample gene set enrichment analysis (ssGSEA) was conducted to investigate immune cell proliferation. The Seurat package was used for the single-cell data analysis, and the limma package was used to identify the differentially expressed genes between the NOA and normal samples. Moreover, we conducted a weighted gene co-expression network analysis (WGCNA) to identify the macrophage-related key modules and genes, and conducted Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses for the functional exploration. To identify the macrophage-related biomarkers, we conducted least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) analyses. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to verify the marker genes present in NOA.

Results

We confirmed that open reading frame 72 gene on chromosome 9 (C9orf72) [area under the curve (AUC) =0.861] and cartilage-associated protein (CRTAP) (AUC =0.917) were the hub genes of NOA, and the RT-qPCR analysis revealed the critical expression of both genes in NOA.

Conclusions

Through the combination of tissue transcriptomic and single-cell RNA-sequencing analyses, we concluded that macrophage infiltration is significant in different subtypes of NOA, and we hypothesized that C9orf72 and CRTAP play critical roles in NOA due to their high expression in macrophages.

Analysis of the Growth and Development of Children Born with ICSI of Epididymal and Testicular Spermatozoa: A Propensity Matching Study

OBJECTIVE

The study aimed to evaluate whether singleton live births (at 0, 1, 6, 12, and 24 months) following intracytoplasmic sperm injection (ICSI) using sperm of different origins (ejaculated or non-ejaculated sperm) are associated with the growth and development of children born.

METHODS

This was a retrospective cohort study conducted at a single center from January 2016 to December 2019. Follow-up data of the children were obtained from the Jiangsu Province Maternal and Child database. A total of 350 singleton live births after fresh embryo transfer (ET) with ICSI were included. Based on the origin of the sperm, the patients were divided into two groups: the ejaculated group (n = 310) and the non-ejaculated group (n = 40). Propensity score matching was used to control for multiple baseline covariates, resulting in 80 singleton live births (ejaculated sperm) matched to 40 singleton live births (non-ejaculated). The non-ejaculated group was further divided into two subgroups: the PESA group (n = 23) and the TESA group (n = 17). The primary outcome of the study was the growth and development of children. Secondary outcomes included the 2PN rate, high-cleavage embryo rate, blastocyst formation rate, and others.

RESULTS

After matching parental age, BMI, occupation, and maternal serum AMH level, there was no significant difference found in the growth and development of children between the non-ejaculated and ejaculated group or the PESA group and TESA group, respectively. However, the 2PN rate and the blastocyst formation rate were higher in the ejaculated group compared to the non-ejaculated group (91.02 and 85.45, P = 0.002) and (67.37 and 56.06, P = 0.019), respectively. The high-quality cleavage embryo rate was also higher in the TESA group compared to the PESA group (85.06 and 65.63, P = 0.001).

CONCLUSION

This study suggests that there are no significant differences in the growth and development of children born following ICSI using sperm of different origins (ejaculated or non-ejaculated). For nonobstructive azoospermia (OA) patients, sperm derived from the testis may be more effective than derived from the epididymis. However, due to the limited sample size of the non-ejaculated group in this study, further investigations with larger sample sizes are needed to validate these findings.

Homeodomain-interacting protein kinase HIPK4 regulates phosphorylation of manchette protein RIMBP3 during spermiogenesis

Nonobstructive azoospermia (NOA) is the most serious form of spermatogenesis abnormalities in male infertility. Genetic factors are important to consider as elements leading to NOA. Although many pathogenic genes have been reported, the causative genes of NOA for many patients are still unknown. In this study, we found ten point mutations in the gene encoding homeodomain-interacting protein kinase 4 (HIPK4) in patients with NOA, and using in vitro studies, we determined a premature termination point mutation (p. Lys490∗, c.1468A>T) that can cause decreased expression of HIPK4. Our phosphoproteomic analysis of Hipk4^−/− testes revealed phosphorylation of multiple proteins regulated by HIPK4 during spermiogenesis. We also confirmed that a substrate of HIPK4 with four downregulated phosphorylation sites matching the xSPx motif is the known manchette-related protein RIMS-binding protein 3, which is required for sperm head morphogenesis. Therefore, we conclude HIPK4 regulates the phosphorylation of manchette protein RIMS-binding protein 3 and plays essential roles in sperm head shaping and male fertility.

Microdissection testicular sperm extraction (micro-TESE) in men with infertility due to nonobstructive azoospermia: summary of current literature

PURPOSE

Nonobstructive azoospermia (NOA) is associated with intrinsic testicular defects that severely impair sperm production. Although NOA invariably leads to infertility, focal sperm production may exist in the testicles of affected patients, which can be retrieved and used for intracytoplasmic sperm injection (ICSI) to generate healthy offspring. However, geographic locations of testicular sperm producing-areas are uncertain, making microsurgical-guided sperm retrieval (microdissection testicular sperm extraction; micro-TESE) an attractive method to identify and retrieve sperm in patients with NOA due to spermatogenic failure. Given the widespread use of micro-TESE, its effectiveness in harvesting sperm and related potential complications need to be clarified.

METHODS

We queried PubMed/MEDLINE for studies published in English, from inception to May 2021, concerning the effect of micro-TESE on sperm retrieval rate (SRR), complication rate and ICSI pregnancy rate-using retrieved testicular sperm in subfertile couples where the male had NOA.

RESULTS

We found 116 articles, including 70 original papers, 32 review articles, and 14 systematic reviews. The evidence accounted for 4895 patients. Micro-TESE retrieved sperm in 46.6% of men with NOA, but SRRs varied considerably (18.4-70.8%) and were mainly related to the treated population characteristics. Concerning the general population of NOA patients who have not undergone previous sperm retrieval (naïve population), the SRR by micro-TESE was 46.8% (1833 of 3914 patients; range 20-70.8%; 28 studies). In studies reporting SR by micro-TESE for men who had failed percutaneous testicular sperm aspiration or non-microsurgical testicular sperm extraction, the SRR was 39.1% (127 of 325 patients; range 18.4-57.1%; 4 studies). Data on adverse events indicated that micro-TESE was associated with low (~ 3%) short-term postoperative complication rates. The fertilizing ability of testicular sperm retrieved by micro-TESE and used for ICSI was adequate (~ 57%), whereas clinical pregnancy and live birth were obtained in 39% and 24% of couples who had an embryo transfer, respectively. The health of the resulting children seems reassuring, but the evidence is limited. The procedure increases sperm retrieval success compared to non-microsurgical retrieval methods, particularly in men with Sertoli cell-only testicular histopathology.

CONCLUSION

We concluded that micro-TESE is an effective and safe method to retrieve sperm from men with NOA-related infertility, with potential advantages over non-microsurgical methods. Nevertheless, high-quality, head-to-head comparative randomized controlled trials by sperm retrieval method, focusing on SRR, live birth rate and assessing long-term adverse events and health of children conceived using testicular sperm from NOA patients are lacking. Therefore, further research is required to determine the full clinical implications of micro-TESE in male infertility treatment.

Sperm Selection Procedures for Optimizing the Outcome of ICSI in Patients with NOA

Retrieving spermatozoa from the testicles has been a great hope for patients with non-obstructive azoospermia (NOA), but relevant methods have not yet been developed to the level necessary to provide resolutions for all cases of NOA. Although performing testicular sperm extraction under microscopic magnification has increased sperm retrieval rates, in vitro selection and processing of quality sperm plays an essential role in the success of in vitro fertilization. Moreover, sperm cryopreservation is widely used in assisted reproductive technologies, whether for therapeutic purposes or for future fertility preservation. In recent years, there have been new developments using advanced technologies to freeze and preserve even very small numbers of sperm for which conventional techniques are inadequate. The present review provides an up-to-date summary of current strategies for maximizing sperm recovery from surgically obtained testicular samples and, as an extension, optimization of in vitro sperm processing techniques in the management of NOA.