stamcel

Stamcel refers to undifferentiated cells with the ability to self-renew and to differentiate into specialized cell types. They occur in many tissues and play a key role in growth, maintenance, and tissue repair. Embryonic stem cells, derived from early-stage embryos, are pluripotent and can give rise to all cell types in the body. Adult or somatic stem cells reside in various tissues (for example, hematopoietic stem cells in blood and mesenchymal stem cells in bone marrow) and are typically multipotent, giving rise to a limited set of related cell types. Induced pluripotent stem cells are adult cells that have been reprogrammed to an embryonic-like pluripotent state, offering a potential source of pluripotent cells without the use of embryos.

Potency levels describe the range of differentiation potential from totipotent (all cell types including placenta) to pluripotent (all body cell types) to multipotent, oligopotent, and unipotent (restricted lineages). Embryonic stem cells are pluripotent; most adult stem cells are multipotent.

Applications include regenerative medicine, cell-based therapies, disease modeling, and drug screening. Stem cells are also used in basic research to understand development and tissue homeostasis. Pluripotent stem cells can form tumors called teratomas if not properly controlled, highlighting safety considerations for clinical use.

Ethical and regulatory issues center on embryo-derived cells and consent; induced pluripotent stem cells mitigate some concerns. Ongoing research aims to understand stem cell biology, tissue niches, and ways to improve safety and efficacy of stem cell–based therapies.