Micro RNA in Semen/Urine from Non-Obstructive Azoospermia Patients as Biomarkers to Predict the Presence of Testicular Spermatozoa and Spermatogonia.

About half of testicular sperm extraction (TESE) procedures in men with non-obstructive azoospermia (NOA), including men with Klinefelter syndrome (KS), are unsuccessful. To avoid unnecessary invasive surgery, biomarkers for spermatozoa were studied. In addition, markers for spermatogonia in testis tissue were explored.

Transcriptomic differences between fibrotic and non-fibrotic testicular tissue reveal possible key players in Klinefelter syndrome-related testicular fibrosis.

Klinefelter syndrome (KS; 47,XXY) affects 1-2 in 1000 males. Most men with KS suffer from an early germ cell loss and testicular fibrosis from puberty onwards. Mechanisms responsible for these processes remain unknown.

Intratesticular xenografting of Klinefelter pre-pubertal testis tissue as potential model to study testicular fibrosis.

Research Question: Is intratesticular xenotransplantation a potential ex-vivo model for studying testicular fibrosis related to Klinefelter syndrome?

Study Design: First, a feasibility study of an ex-vivo model to study testicular fibrosis in patients with Klinefelter syndrome was performed. Testis tissue from boys with pre-pubertal Klinefelter syndrome (n = 3) and controls (n = 2) (<18 years) was grafted to the mouse testis (n = 12) and recovered after 2, 4, 6 and 8 weeks. Part two of this study consisted of a validation of this model, evaluating the effects of the mast cell blocker ketotifen on the histology of the grafts of Klinefelter syndrome (n = 5) and controls (n = 3), transplanted to mice (n = 10), after 4 weeks of ketotifen or saline treatment.

Characterisation of testicular function and spermatogenesis in transgender women.

Study Question: Does gender-affirming treatment prevent full spermatogenesis in transgender women (TW)?

Summary Answer: Adequate hormonal therapy (HT) leads to complete suppression of spermatogenesis in most TW, if serum testosterone levels within female reference ranges are obtained.

What Is Known Already: Gender-affirming treatment in transgender individuals may involve gender-affirming HT. The effects on spermatogenesis in TW remain unclear.

Fertility Preservation in Childhood Cancer: Endocrine Activity in Prepubertal Human Testis Xenografts Exposed to a Pubertal Hormone Environment.

Survivors of childhood cancer are at risk for long-term treatment-induced health sequelae, including gonadotoxicity and iatrogenic infertility. At present, for prepubertal boys there are no viable clinical options to preserve future reproductive potential. We investigated the effect of a pubertal induction regimen with gonadotrophins on prepubertal human testis xenograft development.

Testicular immune cells and vasculature in Klinefelter syndrome from childhood up to adulthood.

Study Question: Is the distribution of immune cells and the testicular vasculature altered in testicular biopsies from patients with Klinefelter syndrome (KS)?

Summary Answer: Increased numbers of macrophages and mast cells, an increased expression of decorin and an increased blood vessel density were found in KS samples compared to controls.

What Is Known Already: Most KS patients are infertile due to an early germ cell loss. From puberty onwards, testicular fibrosis can be detected.

Characterization of the stem cell niche components within the seminiferous tubules in testicular biopsies of Klinefelter patients.

Objective: To characterize the tubular environment in testicular biopsy tissues from patients with Klinefelter syndrome (KS).

Design: Observational immunohistochemical study.

Setting: Academic research unit.

Germ cell loss in Klinefelter syndrome: When and why?

Klinefelter syndrome (KS) is a quite common disorder with an incidence of 1-2 in 1,000 new-born males. Most patients are diagnosed in the light of a clinical checkup when consulting a fertility clinic with an unfulfilled child wish. Infertility in KS patients is caused by a massive germ cell loss, leading to azoospermia in more than 90% of the adult patients.

Does co-transplantation of mesenchymal and spermatogonial stem cells improve reproductive efficiency and safety in mice?

Background: Spermatogonial stem cell transplantation (SSCT) is a promising therapy in restoring the fertility of childhood cancer survivors. However, the low efficiency of SSCT is a significant concern. SSCT could be improved by co-transplanting transforming growth factor beta 1 (TGFβ1)-induced mesenchymal stem cells (MSCs).

Effect of recombinant human vascular endothelial growth factor on testis tissue xenotransplants from prepubertal boys: a three-case study.

Research Question: Does recombinant human vascular endothelial growth factor (VEGF-165) improve the efficiency of human immature testis tissue (ITT) xenotransplantation?

Design: ITT fragments from three prepubertal boys were cultured for 5 days with VEGF-165 or without (control) before xenotransplantation into the testes of immunodeficient mice. Xenotransplants were recovered at 4 and 9 months post-transplantation and vascularization, seminiferous tubule integrity, number of spermatogonia and germ cell differentiation were evaluated by histology and immunohistochemistry.

Results: Transplants from donor 1 and donor 2 treated with VEGF demonstrated higher vascular surface (P = 0.

Co-transplantation of mesenchymal stem cells improves spermatogonial stem cell transplantation efficiency in mice.

Background: Spermatogonial stem cell transplantation (SSCT) could become a fertility restoration tool for childhood cancer survivors. However, since in mice, the colonization efficiency of transplanted spermatogonial stem cells (SSCs) is only 12%, the efficiency of the procedure needs to be improved before clinical implementation is possible. Co-transplantation of mesenchymal stem cells (MSCs) might increase colonization efficiency of SSCs by restoring the SSC niche after gonadotoxic treatment.

Cryopreservation of Human Testicular Tissue by Isopropyl-Controlled Slow Freezing.

Tissue cryopreservation uses very low temperatures to preserve structurally intact living cells in their natural microenvironment. Cell survival is strongly influenced by the biophysical effects of ice during both the freezing and the subsequent thawing. These effects can be controlled by optimizing the fragment size, type of cryoprotectant, and cooling rate.

Exogenous administration of recombinant human FSH does not improve germ cell survival in human prepubertal xenografts.

In a previous study, meiotic activity was observed in human intratesticular xenografts from peripubertal patients. However, full spermatogenesis could not be established. The present study aimed to evaluate whether the administration of recombinant human FSH could improve the spermatogonial survival and the establishment of full spermatogenesis in intratesticular human xenografts.

Does early cell death cause germ cell loss after intratesticular tissue grafting?

Objective: To assess cell death in intratesticular grafts.

Design: Experimental animal study.

Setting: University.

Spermatogonial stem cell preservation in boys with Klinefelter syndrome: to bank or not to bank, that's the question.

Although early development of testis appears normal in boys with Klinefelter syndrome (KS), spermatogonial stem cell (SSC) depletion occurs in midpuberty, leading to infertility. Therefore, freezing of semen samples or testicular tissue sampling could be offered to boys with KS at onset of puberty. However, only in about half of patients with KS, adult or prepubertal, spermatozoa or SSCs can be observed, and to date, no clinical parameters are available to detect patients who might benefit from these techniques.

Orthotopic grafting of cryopreserved prepubertal testicular tissue: in search of a simple yet effective cryopreservation protocol.

Objective: To investigate whether solid-surface vitrification (SSV) is an effective cryopreservation strategy regarding the integrity and function of prepubertal mouse testicular tissue.

Design: Prospective experimental study.

Setting: Academic research unit.

Presence of spermatogonia in 47,XXY men with no spermatozoa recovered after testicular sperm extraction.

Objective: To evaluate the presence of spermatogonia in men diagnosed with Klinefelter syndrome (KS), in whom no testicular spermatozoa were recovered by testicular sperm extraction.

Design: Retrospective case series.

Setting: University hospital.

Mouse spermatogonial stem cells obtain morphologic and functional characteristics of hematopoietic cells in vivo.

Background: The aim of this study was to explore the plasticity and transdifferentiation potential of murine spermatogonial stem cells (SSCs) into hematopoietic cells.

Methods: GFP(+)CD49f(+)H-2K(b-) SSCs of male donor mice were isolated and injected into the bone marrow (BM) of Busulfan-treated GFP(-) female mice. Twelve weeks post-transplantation, the recipients were sacrificed and their BM, peripheral blood (PB) and spleen (SL) cells were collected and evaluated by phenotypical methods, i.

Bone marrow stem cells transplanted to the testis of sterile mice do not differentiate into spermatogonial stem cells and have no protective effect on fertility.

Four months after transplanting bone marrow cells into the testis, no differentiation to spermatogonial stem cells was observed. Bone marrow transplantation had no protective effect on fertility after chemotherapy.

Regeneration of spermatogenesis by grafting testicular tissue or injecting testicular cells into the testes of sterile mice: a comparative study.

Objective: To make a comparison between two different approaches-spermatogonial stem cell transplantation and intratesticular grafting, for preservation and reintroduction of spermatogonial stem cells.

Design: Prospective experimental study.

Setting: Academic medical center and teaching hospital.

Autologous spermatogonial stem cell transplantation in man: current obstacles for a future clinical application.

Fertility preservation is becoming an important issue in the management of the quality of life of prepubertal boys undergoing cancer treatment. At present, the only theoretical option for preservation of fertility in these boys is the preservation of the spermatogonial stem cells for autologous intratesticular stem cell transplantation. In animal models, this technique has shown promising results.