Isolation and culture of human spermatogonial stem cells derived from testis biopsy

In cancer patients, chemo and radiotherapy can cause infertility by damaging spermatogenesis process. This process is based on self-renewal and differentiation of a rare population of the testicular cells called Spermatogonial Stem Cells [SSCs]. Scientists have tried to isolate, enrich and culture Human spermatogonial stem cells, hoping to resolve infertility problems in cancer recovered patients in the future. Spermatogonial stem cells were isolated and purified from human testicular biopsies sample consisting of at least 500,000 and at most 2,000,000 cells. Two enzymatic digestion steps were performed. Enriching methods, differential plating, and specific culture in serum-free medium with added growth factors: human GDNF, bFGF, EGF and LIF was performed on coated dishes. Human spermatogonial stem cell clusters were observed after 7 to 10 days in specific culture, then after several passages and successful expanding duration of 52 days, the cells were evaluated by three layer immunocytochemistry test [LSAB] to stain GPR125 protein as a surface marker in human spermatogonial stem cells. In current study human spermatogonial stem cell were isolated and expanded with the least manipulations in comparison with the other usual isolation methods like florescent or magnetic activated cell sorting. In contrast to the other SSCs isolation and culture methods, this system is based on the testicular biopsies against large samples, thus suggested method in this study is closer to clinical usage in the future

Propagation of human germ stem cells in long-term culture

Spermatogonial stem cells [SSCs], a subset of undifferentiated type A spermatogonia, are the foundation of complex process of spermatogenesis and could be propagated in vitro culture conditions for long time for germ cell transplantation and fertility preservation. The aim of this study was in vitro propagation of human spermatogonial stem cells [SSCs] and improvement of presence of human Germ Stem Cells [hGSCs] were assessed by specific markers POU domain, class 5, transcription factor 1 [POU5F1], also known as Octamer-binding transcription factor 4 [Oct-4] and PLZF [Promyelocytic leukaemia zinc finger protein]. Human testicular cells were isolated by enzymatic digestion [Collagenase IV and Trypsin]. Germ cells were cultured in Stem-Pro 34 media supplemented by growth factors such as glial cell line-derived neurotrophic factor, basic fibroblast growth factor, epidermal growth factor and leukemia inhibitory factor to support self-renewal divisions. Germline stem cell clusters were passaged and expanded every week. Immunofluorecent study was accomplished by Anti-Oct4 antibody through the culture. The spermatogonial stem cells genes expression, PLZF, was studied in testis tissue and germ stem cells entire the culture. hGSCs clusters from a brain dead patient developed in testicular cell culture and then cultured and propagated up to 6 weeks. During the culture Oct4 were a specific marker for identification of hGSCs in testis tissue. Expression of PLZF was applied on RNA level in germ stem cells. hGSCs indicated by SSCs specific marker can be cultured and propagated for long-term in vitro conditions

vitro culture of human testicular stem cells on feeder-free condition

Spermatogonial stem cells are subpopulation of spermatogonial cells in testis tissue that support beginning and maintenance of spermatogenesis. Ubiquitin carboxy-terminal hydrolase L1 [UCHL1] could be a specific marker for identification of spermatogonial stem cells including spermatogonial sperm cells [SSCs] in testis tissue and during the culture; therefore we undertook this study to culture these human testicular stem cells [hTSCs] in vitro and approved the presence of human testicular stem cells [hTSCs] by UCHL1, also known as PGP9.5. Enzymatic digestion of human testicular biopsies was done by collagenase IV [4 mg/ml] and trypsin [0.25%]. Differential plating of testicular cells in DMEM/F12 and 10% FBS was applied for 16 hr. Floating cells were collected and transferred onto laminin-coated plates with Stem-Pro 34 media supplemented with growth factors of GDNF, bFGF, EGF and LIF to support self-renewal divisions; testicular stem cell clusters were passaged every 14 days for two months. Spermatogonial cells propagation was studied through Expression of UCHL1 in testis tissue and the entire testicular stem cell culture. Testicular stem cell clusters from 10 patients with obstructive azoospermia were cultured on laminin-coated plates and subsequently propagated for two months. The average of harvested viable cells was approximately 89.6%. UCHL1 was expressed as specific marker in testicular stem cells entire the culture. Human testicular stem cells could be obtained from human testicular tissue by a simple digestion, culturing and propagation method for long-term in vitro conditions. Propagation of these cells approved by specific marker UCHL1, during the culture period

[Fertility preservation in men after cancer treatment; a review article]

Some cases of male infertility are due to the destructive side-effects of anticancer treatment methods such as chemo and radiotherapies on germ cell lines. The increase in the survival rate of cancer patients who undergo treatment, especially children, has drawn attention to fertility preservation. The most common and effective technique in preserving male fertility is sperm freezing and its subsequent IVF. Children cannot efficiently produce sperm because of their spermatogonial immaturity. One of the strategies to maintain fertility in these patients is to preserve the testes or the germ cells by freezing them for their later maturation and production of fertile sperm, although the state in which the spermatogonia may not undergo maturation is one of the main obstacles faced in this method. Therefore, scientists have attempted to transplant cryopreserved testis tissues or produce in vitro-matured spermatozoa in this group of patients upon anticancer treatment. In this study we reviewed the germ cell biology, the side-effects of chemo and radiotherapies on germ cells and fertility preservation techniques in adults and children undergoing anticancer treatment