Immune Disease Institute

Stem Cells

It is now appreciated that essentially all tissues and organs contain minor populations of primitive stem cells that are integral first in the developing fetus for the generation of tissues and organs, and later in the adult for ongoing homeostatic tissue maintenance, and regeneration after injury. The defining features of stem cells: that of self-renewal and multi-potency, enable stem cells to both perpetuate themselves, and give rise to mature effector cell types in a sustained fashion throughout our lifetime. These properties have positioned stem cells at the forefront of the burgeoning field of regenerative medicine whose ultimate goal is to harness the enormous clinical potential of stem cells to treat both heritable and acquired degenerative conditions and diseases.

Historically, hematopoietic stem cells represent a paradigm for the therapeutic potential of stem cells, as they are the only stem cells in routine clinical use. Hematopoietic stem cells are used to treat a variety of blood cell diseases, especially leukemia and lymphoma. Disorders in the stem cell compartment are believed to be responsible, at least in part, for a broad group of blood diseases including a wide variety of hematological malignancies, myelodysplastic syndromes, and aplastic anemias. Therefore a continued effort to understand the fundamentals of hematopoietic stem cell biology will enhance understanding and treatment of blood diseases.

Many solid cancers (including breast, colon, lung, glioblastoma, and melanoma) are also thought to be initiated and sustained by rare tumor-initiating cells, termed cancer stem cells. Cancer stem cells are resistant to current cancer therapies and are therefore thought to play a big role in tumor resistance and relapse. Many of the central properties of normal stem cells are shared with cancer stem cells. Therefore the more we can understand both normal and tumor stem cell biology, the better we will be able to treat cancer.

Investigators at PCMM/IDI are pursuing numerous lines of investigation in the area of stem cell biology including:

• Elucidating the molecular basis of stem cell self-renewal and multi-potency.
• Identifying the cellular components of the stem cell niche.
• Understanding the in vivo dynamics of stem cell migration, trafficking and homing.
• Uncovering the molecular mechanisms underlying cancer stem cell self-renewal and tumorigenicity.
• Developing novel cancer treatment strategies that target drug-resistant cancer stem cells.
• Elucidating the cellular and molecular mechanisms underlying stem cell aging, and how this contributes to the onset of age-associated disease.