Not a Fountain of Youth
Researchers at the Stanford University School of Medicine have discovered that as people age, their hematopoietic stem cells (HSC) could not differentiate into B lymphocytes as well and typically became myeloid cells by comparing HSC from 15 elderly people and 28 younger people, all of whom were healthy. The bone marrow of mice that received HSCs from human donors had more myeloid cells compared to lymphoid cells. Genes related to age that played a role in the cell cycle, growth, division, DNA repair and death of cells were upregulated which means that do not enter the cell cycle at the correct time. This may result in an elderly person’s immune system not being fully functional and explain why blood cancers such as acute myeloid leukemia are more prevalent in this age group.
Recipient Could Also Be Donor
Paris researchers have proven that hematopoietic stem cells (HSCs) incubated with growth factors to make them differentiate into RBCs mature and survive in the body. They showed that cultured red blood cells (cRBCs) matured in the body by injecting them into four mice. Then the HSCs from a donor were incubated and the cRBCs put back into the donor. Five days later, 94 to 100 percent of the circulating cRBCs were still alive and by 26 days it was 41 to 63 percent. These numbers are comparable to the normal lifespan and survival of RBCs that have matured in the bone marrow before entering the bloodstream. Researchers believe once the technique is improved upon, this alternative will be a solution to the worldwide RBC shortage and the side effects of current blood transfusions reduced.