Pituitary progenitor cells tracked down by side population dissection.
The pituitary gland represents the endocrine core, governing the body's hormonal landscape by adapting its cellular composition to changing demands. It is assumed that stem/progenitor cells are involved in this remodeling. Recently, we uncovered a candidate stem/progenitor cell population in the anterior pituitary. Here, we scrutinized this "side population" (SP) and show that, unexpectedly, not the subset expressing high levels of "stem cell antigen-1" (Sca1(high)) but the remainder non-Sca1(high) fraction clusters the pituitary progenitor cells. Transcriptomal interrogation revealed in the non-Sca1(high) SP upregulated expression of the pituitary stem/progenitor cell markers Sox2 and Sox9, and of multiple factors critically involved in pituitary embryogenesis. The non-Sca1(high) SP encloses the cells that generate spheres and display multipotent hormone differentiation capacity. In culture conditions selecting for the non-Sca1(high) subset within the SP, stem cell growth factors that induce SP expansion, affect transcription of embryonic factors, suggesting impact on a developmental program that unfolds within this SP compartment. Non-Sca1(high) SP cells, revealed by Sox2 expression, are observed in the postulated periluminal stem/progenitor cell niche, but also in small groups scattered over the gland, thereby advocating the existence of multiple niches. In early postnatal mice undergoing a pituitary growth wave, Sox2(+) cells are more abundant than in adults, concordant with a larger SP and higher non-Sca1(high) proportion. Together, we tracked down pituitary progenitor cells by SP phenotype, and thus provide a straightforward method to isolate and scrutinize these cells from the plastic pituitary ex vivo, as well as a culture system for in-depth exploration of their regulatory network.
Chen
Jianghai
J
Department of Molecular Cell Biology, Laboratory of Tissue Plasticity, University of Leuven (KU Leuven), Leuven, Belgium.
Gremeaux
Lies
L
Fu
Qiuli
Q
Liekens
Daisy
D
Van Laere
Steven
S
Vankelecom
Hugo
H
D000818:Animals; D000067696:Ataxin-1; D000067528:Ataxins; D002449:Cell Aggregation / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002469:Cell Separation / Q000379:methods*; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D047108:Embryonic Development / Q000187:drug effects; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D016678:Genome / Q000235:genetics; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology; D051379:Mice; D039902:Multipotent Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D010641:Phenotype; D010902:Pituitary Gland / Q000166:cytology* / Q000187:drug effects / Q000196:embryology; D010903:Pituitary Gland, Anterior / Q000166:cytology; D055748:SOXB1 Transcription Factors / Q000378:metabolism; D055153:Stem Cell Niche / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
D000067696:Ataxin-1; D000067528:Ataxins; C000593750:Atxn1 protein, mouse; D016895:Culture Media, Serum-Free; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D055748:SOXB1 Transcription Factors; C527783:Sox2 protein, mouse