Purification of GFR α1+ and GFRα1– Spermatogonial Stem Cells Reveals a Niche-Dependent Mechanism for Fate Determination

Publication date: Available online 11 January 2018 Source:Stem Cell Reports Author(s): Alina Garbuzov, Matthew F. Pech, Kazuteru Hasegawa, Meena Sukhwani, Ruixuan J. Zhang, Kyle E. Orwig, Steven E. Artandi Undifferentiated spermatogonia comprise a pool of stem cells and progenitor cells that show heterogeneous expression of markers, including the cell surface receptor GFRα1. Technical challenges in isolation of GFRα1+ versus GFRα1– undifferentiated spermatogonia have precluded the comparative molecular characterization of these subpopulations and their functional evaluation as stem cells. Here, we develop a method to purify these subpopulations by fluorescence-activated cell sorting and show that GFRα1+ and GFRα1– undifferentiated spermatogonia both demonstrate elevated transplantation activity, while differing principally in receptor tyrosine kinase signaling and cell cycle. We identify the cell surface molecule melanocyte cell adhesion molecule (MCAM) as differentially expressed in these populations and show that antibodies to MCAM allow isolation of highly enriched populations of GFRα1+ and GFRα1– spermatogonia from adult, wild-type mice. In germ cell culture, GFRα1– cells upregulate MCAM expression in response to glial cell line-derived neurotrophic factor (GDNF)/fibroblast growth factor (FGF) stimulation. In transplanted hosts, GFRα1– spermatogonia yield GFRα1+ spermatogonia and restore spermatogenesis, albeit at lower rates than their GFRα1...
Source: Stem Cell Reports - Category: Stem Cells Source Type: research