Stem Cell Research

Disease / Phenomenon

Stem cell research studies undifferentiated cells capable of both self-renewal and differentiation into specialized cell types, and how that capacity might be directed for repair and regeneration. Several classes are distinguished: embryonic stem cells, pluripotent and able to form any cell of the body; adult or somatic stem cells such as hematopoietic and mesenchymal populations, with more restricted potential; and induced pluripotent stem cells, generated by reprogramming ordinary adult cells and thereby avoiding much of the ethical debate surrounding embryonic sources. Applications span disease modeling, drug screening on patient-derived tissue, and regenerative therapy, though hematopoietic transplantation remains the most firmly established clinical use.

The governing biology concerns how stemness is maintained and lost. Core transcription factors OCT4, SOX2, NANOG, and KLF4 sustain the pluripotent state, and forced expression of a small set of these reprograms differentiated cells. Signaling through Wnt/beta-catenin, Notch, Hedgehog, BMP, and FGF pathways directs lineage commitment, while epigenetic mechanisms — DNA methylation, histone modification, chromatin accessibility — record and stabilize each decision. The stem cell niche supplies mechanical and paracrine cues, and metabolic state, shifting between glycolysis and oxidative phosphorylation, is itself instructive. Senescence and telomere maintenance limit long-term capacity. This page separates these processes into pathways and biomarkers.