A biological reserve for the whole family
Stem cells are unspecialized cells, still without an established function inside the body, and are capable of unlimited self-renewal, reproducing themselves by cellular division. Each stem cell can divide up both to give life to a daughter cell equal to the mother and to a cell that will go on to construct one of the many tissues of the human body.
On the basis of their potentiality in terms of differentiation, stem cells can be defined as:
- Totipotent: when they can produce all the tissues and every type of cell, including those of embryonic appendages. They are thus already present in the morula, an aggregate of cells that form in the initial stages of embryonic development.
- Pluripotent: those that can differentiate into all types of cells that we find in an adult human, but not into cells that make up extra-embryonic tissue (e.g. embryonic stem cells).
- Multipotent: stem cells that can only differentiate into some types of cell (e.g. cord cells, marrow cells, cells from peripheral blood or tissue-specific cells such as epithelial cells and adipose cells).
- Unipotent: when they can only produce one cell type, specialised and in function of the tissue to construct or regenerate.
Stem cells are usually divided into embryonic or somatic according to their provenance. The former are obtained by means of culture and come from the internal cells of a blastocyst, an aggregate of cells progenitor of the embryo: their use for therapeutic purposes causes the destruction of the embryo, with ethical or religious implications, and is banned in Italy. Somatic stem cells are undifferentiated cells that can be found among specialised cells of a specific tissue and are mainly multipotent.
Stem cells from the umbilical cord include somatic stem cells that, compared to other sources, represent the “biological witness” of the newborn child and a potential diagnostic source.
The total absence of immunological experience (by environmental and food contamination) also makes them a precious biological reserve for treating important pathologies, potentially useful for the whole family.
During the early months of pregnancy the placenta produces stem cells which, during gestation, are transferred to the foetal liver and then to the bone marrow. The stimulus from the unborn child’s central nervous system induces the bone marrow to produce and mobilize stem cells that consequently transit in a whirling motion in the umbilical cord.
| NEONATAL STEM CELLS | |
| Recently identified stem cells: | USSC – Unrestricted Somatic Stem Cells |
| VSEL – Very Small Embryonic-Like Cells | |
| Multipotent stem cells: | HSC – Haematopoietic Stem Cells |
| Mesenchymal Stem Cells, able to differentiate into bone, cartilage, muscle and fat cells | |
| Endothelial Progenitor Cells (EPC), able to differentiate into cells that make up the lining of blood vessels. | |
| CHARACTRISTICS AND ADVANTAGES of neonatal stem cells | |
| Easy and painless collection | |
| Sterility | |
| Versatility (high compatibility) | |
| Immediate availability (of cryopreserved units) | |
| More immature cells (do not induce rejection or chronic GVHD) | |
| Plasticity (ability to produce various types of tissue) | |
| Cellularity (concentration of Treg lymphocytes, EPC, MSC with anti-inflammatory effect) | |
| Ethicality | |
| Post-implant recovery (slower in terms of neutrophils and platelets) |
| DIFFERENCES BETWEEN | CORD STEM CELLS (UCB) | ADULT STEM CELLS (HSC) |
| T-cellular response to alloantigens/mitogens | Modest response | Vigorous response |
| Proportion of CD34+ and CD45RA+ cells | More than T cells | Population of CD45RA+/CD45RO+ |
| Proportion of Haematopoietic Progenitor cells | More than adult stem cells | Reduced |
| Proliferation of CD34+ cells in response to stimulus with cytokine in vitro |
More than adult stem cells | Reduced |
Source: A. Stanevsky, A. Shimoni, R.Yerushalmi, A.Nagler “Cord Blood Stem Cells for Hematopoietic Transplantation” 2010 – Stem Cell Rev and Rep
