Recent advances in isolation, identification, and culture of mammalian spermatogonial stem cells / 亚洲男科学杂志(英文版)

Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells (SSCs). SSCs, the only male reproductive stem cells that transmit genetic material to subsequent generations, possess an inherent self-renewal ability, which allows the maintenance of a steady stem cell pool. SSCs eventually differentiate to produce sperm. However, in an in vitro culture system, SSCs can be induced to differentiate into various types of germ cells. Rodent SSCs are well defined, and a culture system has been successfully established for them. In contrast, available information on the biomolecular markers and a culture system for livestock SSCs is limited. This review summarizes the existing knowledge and research progress regarding mammalian SSCs to determine the mammalian spermatogenic process, the biology and niche of SSCs, the isolation and culture systems of SSCs, and the biomolecular markers and identification of SSCs. This information can be used for the effective utilization of SSCs in reproductive technologies for large livestock animals, enhancement of human male fertility, reproductive medicine, and protection of endangered species.

[Gene expression and functional profiles related to differentiation of human hepatic progenitor cells].

OBJECTIVE: To identify the genes playing a functional role in differentiation of human hepatic progenitor cells to hepatocytes by comparing the gene expression and functional profiles of the two cell types. METHODS: mRNA was isolated from human fetal hepatic progenitor cells (hFHPCs) and functional hepatocyte-like cells (HLCs) that had differentiated from hFHPCs. Global gene expression profiling was performed on triplicate samples of each cell type. The differential gene expression was analyzed using volcano plot filtering and functional annotation was performed using the Database for Annotation, Visualization, and Integrated Discovery (DAVID). RESULTS: Compared to the hFHPCs, the HLCs had a total of 1878 significantly up-regulated genes and 1441 significantly down-regulated genes. The up-regulated genes included functional groups related to the hexose metabolic process, positive regulation of apoptosis, angiogenesis, regulation of cell motion, and protein amino acid phosphorylation. The down-regulated genes included functional groups related to cell cycle, DNA metabolic process, cytoskeleton organization, regulation cell cycle, and chromosome segregation. CONCLUSION: Differentiation of HLCs from hFHPCs may involve increased expression of genes related to hepatocyte function and decreased expression of genes related to cell cycle regulation.