What are Stem Cells?
Without stem cells, wounds would never heal, your skin and blood could not continually renew themselves, fertilized eggs would not grow into babies, and babies would not grow into adults. These cells are the body’s reserve, they will only activate when you need either to produce more stem cells or make more of other specialized cells. All multicellular organisms, from plants to humans, need stem cells.
What is a Hematopoietic Stem Cell?
The stem cells that form blood and immune cells are known as hematopoietic stem cells (HSCs). They are ultimately responsible for the constant renewal of blood—the production of billions of new blood cells each day. A hematopoietic stem cell is a cell-isolated from the blood or bone marrow that can re-new itself, can differentiate itself into a variety of specialized cells, and can undergo programmed cell death, call apoptosis. HSCs are the first stem cells to be used medically. When a patient receives a bone marrow transplant during treatment for leukemia or other diseases—where the normal development of blood cells is awry, HSCs supply the needed new blood. HSC are the easiest stem cells to isolate, and have been used in therapy for decades. Therapies use a patient’s own cells or cells from donors that, from a white blood cell’s perspective, resemble the patient. Otherwise, the patient’s immune system may attack the transplanted cells. Experimental therapies are trying to use purified populations of HSCs or looking for drugs that can cause a patient’s own HSCs to proliferate without a transplant. These cells are used in hematopoietic cell transplantation procedures and are responsible for the lifelong production and maintenance of all blood and immune cells.
How Does Sleep Effect Hematopoietic Stem Cells?
While hematopoietic cell transplantation is a standard therapeutic procedure for various malignant and non-malignant diseases, the impact of sleep on hematopoietic cell transplantation has not been investigated. Sleep an the function of HSCs while not studied preciously is important, as more than 100 million people around the world, including potential bone marrow (BM) donors, suffer from disorders of sleep and wakefulness. The study shows that in donor mice sleep deprivation reduces the ability of its hematopoietic stem cells to engraft and reconstitute the blood and bone marrow of a an irradiated (exposed to radiation) by more than 50%.
Charlotte Curnin ’17
Rolls, A. (2915). Sleep disruption impairs haematopoietic stem cell transplantation in mice.
Nature, 6. http://dx.doi.org/10.1038/9516