Lgr5positive

Lgr5-positive cells are cells that express the gene LGR5, which encodes a leucine-rich repeat-containing G-protein coupled receptor. LGR5 is used as a marker of adult stem cells in several epithelia and marks a population with high proliferative potential. In the intestine, LGR5+ cells reside at the base of the crypts, interspersed with Paneth cells, and constitute a rapidly cycling stem cell pool able to self-renew and differentiate into all intestinal epithelial lineages, including enterocytes, goblet cells, enteroendocrine cells, and Paneth cells.

Lineage-tracing studies in mice using Lgr5 promoter–driven Cre recombinase have shown that individual LGR5+ cells can generate entire crypts and regenerate intestinal units after injury. LGR5 marks similar multipotent progenitors in other tissues as well, such as hair follicles and gastric glands, indicating a broader role for this marker in adult stem cell biology.

In vitro, LGR5+ cells can be cultured as three-dimensional organoids that recapitulate many features of the native tissue. Organoid formation typically requires Wnt signaling, RSPOs, EGF, and other factors; RSPOs act through LGR5 to potentiate Wnt signaling by inhibiting RNF43/ZNRF3, supporting self-renewal and expansion.

Clinical and research relevance centers on tissue regeneration and cancer biology. LGR5+ populations are studied as potential drivers of tissue repair and as cells of origin in certain cancers. Expression and activity of LGR5 are context-dependent and regulated by the niche, so LGR5 is a useful but not universal marker of stemness.