Umbilical Cord Blood Hematopoietic Stem Cells

The use of umbilical cord blood (UCB) for therapies is advantageous because of its ease of access, non-invasive collection procedures, and more plasticity for multi-differentiation. UCB contains a large source of hematopoietic stem cells (HSCs) that are capable of self-renewal, have increased sensitivity to various factors, and are able to generate erythroid and myeloid progenitor colonies. Specifically, the proliferation capacity of human umbilical cord blood mononuclear progenitor cells (HUCBC) are much higher than similar cells in bone marrow. From the UCB, mononuclear cells are isolated and cultured in medium, expanded, and differentiated into the desired cell type.

HUCBC CD34+ cells are cultured with various cytokines and interleukins to give rise to various cell types, from red blood cells, to B-, T-, and Natural Killer Cells. The content of these cells depends and changes based on the gestational age. Because HUCBC are largely immature, do not express class II HLA antigens, and do not produce as many cytokines and immunoglobulins as adult lymphocytes, transplantation with these cells means low levels of cytotoxicity and immunological reactions.

Cord blood transplants have been used to treat conditions from aplastic anemia, B-thalassemia, X-linked lymphoproliferative syndrome, Hunter’s syndrome, acute lymphoid leukemia, chronic myeloid leukemia, to neuroblastoma. This highlights the adaptive nature of these cells.