Induced pluripotent stem cells (iPSCs)

Definition

Induced pluripotent stem cells (iPSCs) are a type of stem cell that can be generated from adult cells through the introduction of specific genes and factors, reprogramming them back into a pluripotent state. This unique ability allows iPSCs to differentiate into virtually any cell type in the body, making them a powerful tool for regenerative medicine, cell sourcing, and tissue engineering applications.

5 Must Know Facts For Your Next Test

1. iPSCs were first discovered in 2006 by Shinya Yamanaka, which earned him the Nobel Prize in Physiology or Medicine in 2012.
2. Unlike embryonic stem cells, iPSCs can be derived from adult tissues, providing an ethical advantage and avoiding issues related to embryo destruction.
3. iPSCs can be used for drug testing and disease modeling, as they can be differentiated into patient-specific cell types to study disease mechanisms.
4. The generation of iPSCs involves delivering four key transcription factors (OCT4, SOX2, KLF4, and c-MYC) into somatic cells to induce reprogramming.
5. iPSCs hold promise in regenerative medicine as they could potentially replace damaged tissues or organs without the risk of immune rejection since they can be derived from the patient’s own cells.

Review Questions

• How does the process of reprogramming adult somatic cells into iPSCs enhance our understanding of pluripotency?
  • The process of reprogramming adult somatic cells into iPSCs showcases how specific transcription factors can revert specialized cells back to a pluripotent state. This highlights the mechanisms behind pluripotency and offers insights into cellular development and differentiation pathways. By studying iPSCs, researchers can better understand how pluripotency is maintained and how it can be manipulated for therapeutic applications.
• Discuss the ethical advantages of using iPSCs over embryonic stem cells in regenerative medicine.
  • Using iPSCs provides significant ethical advantages because they are derived from adult somatic cells rather than embryos. This eliminates the moral concerns associated with embryo destruction, allowing researchers to access pluripotent stem cells without facing ethical dilemmas. Furthermore, since iPSCs can be generated from a patient's own cells, it reduces the risk of immune rejection when used for therapeutic purposes.
• Evaluate the potential impact of iPSCs on tendon and ligament tissue engineering and discuss the challenges that remain.
  • iPSCs offer exciting possibilities for tendon and ligament tissue engineering due to their ability to differentiate into various cell types needed for these tissues. They could potentially facilitate the development of biologically engineered grafts that promote healing and restore function. However, challenges remain regarding their efficient differentiation into tendon- or ligament-specific cell types, ensuring functional integration with existing tissue, and addressing any tumorigenic risks associated with using reprogrammed cells in clinical applications.

Related terms

Pluripotency: The ability of a stem cell to develop into any cell type in the body, giving rise to all three germ layers: ectoderm, mesoderm, and endoderm.

Reprogramming: The process of converting specialized somatic cells into pluripotent stem cells by introducing specific transcription factors that alter gene expression.

Tissue Engineering: A field that focuses on creating biological substitutes to restore, maintain, or improve the function of damaged tissues and organs using cells, biomaterials, and engineering principles.