In Vitro and In Vivo Determinations of The Anti-GDNF Family Receptor Alpha 1 Antibody in Mice by Immunochemistry and RT-PCR

A Fundamental Research in In Vitro Spermatogonial Stem Cell Culturing: What Are Clump Cells?

Spermatogonial stem cells (SSCs) are a small group of testicular cells located in the basement membrane of seminiferous tubules and can balance self-renewal and differentiation during spermatogenesis. Our in vitro culture experiments of mouse SSCs indicated heterogeneity of cultured cells. Highly compact colonies were observed next to SSC colonies, which we call clump cells. We used immunocytochemical staining to identify SSCs and somatic cells with VASA and Vimentin antibodies. Subsequently, we compared mRNA expression levels of VASA, DAZL, PLZF, GFRA1, Lin28, Kit, Myc and Vimentin genes using Fluidigm real-time RT-polymerase chain reaction in clump cells, SSCs, and testicular stromal cells. To better understand the functions of selected genes, we created a protein-protein interaction network and performed an enrichment analysis using different databases. Based on the data collected, we state that clump cells do not express the molecular markers of SSCs, so we cannot consider them as SSCs; however, we claim that these cells are altered SSCs. The molecular mechanism of this conversion is still obscure. Therefore, this study can support the analysis of germ cell development both in vitro and in vivo. In addition, it can be effective in finding new and more efficient treatments for male infertility.

Comparison of POU5F1 gene expression and protein localization in two differentiated and undifferentiated spermatogonial stem cells

The POU domain, class 5, transcription factor 1 (POU5F1), plays a vital role in creating pluripotency and maintaining self-renewal of the spermatogonial stem cells (SSCs). In this experimental research, the gene and protein expression of POU5F1 in two populations of differentiated and undifferentiated spermatogonia were examined, by immunohistochemistry (IMH), immunocytochemistry (ICC) and Fluidigm real-time RT-PCR. Our study was extended with online databases and the creation of PPI networks. The results indicated that the POU5F1 protein was localized in the basal compartment of seminiferous tubules. Under in vitro conditions, isolated SSC colonies were ICC-positive for the POU5F1, but the protein expression level of POU5F1 in the undifferentiated populations was higher than that in differentiated. A significant POU5F1 mRNA expression was seen in passage 4 compared to passage 0 for both populations. POU5F1 has a significantly higher mRNA expression in undifferentiated SSCs than that in differentiated SSCs, also in mESCs than in SSC-like cells. Bioinformatic analysis on POU5F1 shows its impressive connection with other genes involved in spermatogonia differentiation. These results support the advanced investigations of spermatogonia differentiation, both in vitro and in vivo. A better understanding of the POU5F1 gene and its function during differentiation will give the scientific community an open perspective for the development of direct differentiation of SSC to other male germline cells which is very important in infertility treatment.

VASA protein and gene expression analysis of human non-obstructive azoospermia and normal by immunohistochemistry, immunocytochemistry, and bioinformatics analysis

VASA, also known as DDX4, is a member of the DEAD-box proteins and an RNA binding protein with an ATP-dependent RNA helicase. The VASA gene expression, which is required for human germ cell development, may lead to infertility. Immunocytochemistry and immunohistochemistry were used to examine the expression of VASA protein in the human testis sections of azoospermic patients, in-vitro and in-silico models. Some studies of fertile humans showed VASA expression in the basal and adluminal compartments of seminiferous tubules. Our Immunocytochemistry and immunohistochemistry in infertile humans showed expression of VASA in the luminal compartments of the seminiferous tubule. The immunohistochemical analysis of three human cases with different levels of non-obstructive azoospermia revealed a higher expression of VASA-positive cells. For this purpose, Enrichr and Shiny Gene Ontology databases were used for pathway enrichment analysis and gene ontology. STRING and Cytoscape online evaluation were applied to predict proteins' functional and molecular interactions and performed to recognize the master genes, respectively. According to the obtained results, the main molecular functions of the up-regulated and downregulated genes include the meiotic cell cycle, RNA binding, and differentiation. STRING and Cytoscape analyses presented seven genes, i.e., DDX5, TNP2, DDX3Y, TDRD6, SOHL2, DDX31, and SYCP3, as the hub genes involved in infertility with VASA co-function and protein-protein interaction. Our findings suggest that VASA and its interacting hub proteins could help determine the pathophysiology of germ cell abnormalities and infertility.

Actions and Roles of FSH in Germinative Cells

Follicle stimulating hormone (FSH) is produced by the pituitary gland in a coordinated hypothalamic-pituitary-gonadal (HPG) axis event, plays important roles in reproduction and germ cell development during different phases of reproductive development (fetal, neonatal, puberty, and adult life), and is consequently essential for fertility. FSH is a heterodimeric glycoprotein hormone of two dissociable subunits, α and β. The FSH β-subunit (FSHβ) function starts upon coupling to its specific receptor: follicle-stimulating hormone receptor (FSHR). FSHRs are localized mainly on the surface of target cells on the testis and ovary (granulosa and Sertoli cells) and have recently been found in testicular stem cells and extra-gonadal tissue. Several reproduction disorders are associated with absent or low FSH secretion, with mutation of the FSH β-subunit or the FSH receptor, and/or its signaling pathways. However, the influence of FSH on germ cells is still poorly understood; some studies have suggested that this hormone also plays a determinant role in the self-renewal of germinative cells and acts to increase undifferentiated spermatogonia proliferation. In addition, in vitro, together with other factors, it assists the process of differentiation of primordial germ cells (PGCLCs) into gametes (oocyte-like and SSCLCs). In this review, we describe relevant research on the influence of FSH on spermatogenesis and folliculogenesis, mainly in the germ cell of humans and other species. The possible roles of FSH in germ cell generation in vitro are also presented.

Step by Step about Germ Cells Development in Canine

Simple Summary

The progression of germ cells is a remarkable event that allows biological discovery in the differ-entiation process during in vivo and in vitro development. This is crucial for understanding one toward making oogenesis and spermatogenesis. Companion animals, such as canine, could offer new animal models for experimental and clinical testing for translation to human models. In this review, we describe the latest and more relevant findings on germ cell development. In addition, we showed the methods available for obtaining germ cells in vitro and the characterization of pri-mordial germ cells and spermatogonial stem cells. However, it is necessary to further conduct basic research in canine to clarify the beginning of germ cell development.

Abstract

Primordial germ cells (PGCs) have been described as precursors of gametes and provide a connection within generations, passing on the genome to the next generation. Failures in the formation of gametes/germ cells can compromise the maintenance and conservation of species. Most of the studies with PGCs have been carried out in mice, but this species is not always the best study model when transposing this knowledge to humans. Domestic animals, such as canines (canine), have become a valuable translational research model for stem cells and therapy. Furthermore, the study of canine germ cells opens new avenues for veterinary reproduction. In this review, the objective is to provide a comprehensive overview of the current knowledge on canine germ cells. The aspects of canine development and germ cells have been discussed since the origin, specifications, and development of spermatogonial canine were first discussed. Additionally, we discussed and explored some in vitro aspects of canine reproduction with germ cells, such as embryonic germ cells and spermatogonial stem cells.