LGR5 (Leucine-rich repeat-containing G-protein-coupled receptor 5) is a transmembrane receptor best known as a marker of adult stem cells, particularly in tissues like the intestine, hair follicles, and stomach. It functions as a co-receptor for the Wnt/β-catenin signaling pathway, playing a critical role in maintaining stem cell pluripotency, tissue regeneration, and homeostasis. Dysregulation of LGR5 is linked to cancer progression, as its overexpression is observed in colorectal, gastric, and other malignancies, often correlating with tumor-initiating "cancer stem cells" and poor prognosis.
LGR5 antibodies are essential tools for detecting and characterizing LGR5-expressing cells in research. They enable visualization of stem cell niches, tracking cell fate during development or regeneration, and exploring LGR5's role in disease. Polyclonal and monoclonal antibodies targeting specific extracellular or intracellular epitopes have been developed, though challenges like cross-reactivity with homologous receptors (e.g., LGR4 or LGR6) or variability in staining protocols require careful validation.
Recent studies also highlight LGR5 as a therapeutic target, spurring interest in antibody-based therapies or diagnostics. However, inconsistent reports on its expression patterns underscore the need for standardized, high-specificity antibodies. Despite these hurdles, LGR5 antibodies remain pivotal in advancing stem cell biology, oncology, and regenerative medicine research.