AUTOIMMUNITY
Failure of an organism to recognise its own constituent parts as self, which allows an immune response against its own cells and tissues.
AUTO MAINTENANCE
Division cycles that repeatedly generate a daughter cell that is identical to the original cell and has the latent ability to differentiate. It is the property that defines stem cells.
BLASTOCYST
The human blastula or blastocyst is an aggregate of cells deriving from the cells deriving from the mitotic division of the zygote, which first become a morula and then a blastocyst.
BL3 (Clean room)
A clean room is an environment built and used so as to eliminate the introduction, generation and retention of airborne particles, enabling activities that are sensitive to contamination. It is an environment where parameters like temperature, humidity, number of particles and differential pressure rates between various environments are monitored. Under all conditions of operation the air filter ventilation must keep a positive pressure with regard to the three lower-class surrounding areas and ensure effective air exchange.
BONE MARROW
Bone marrow is soft tissue that is found inside the hollow interior of bones. It is the main seat of haematopoiesis, the process of producing blood cells. It accounts for 4% of total body weight, i.e. it weighs about 2.6 kg in adults.
CELL THERAPY
The term “cell therapy” indicates a method of treatment in which drugs are replaced by cells. More recently, the term has been used mainly to indicate procedures that involve the use of well-characterised cellular subpopulations subjected to particular treatments, e.g. cellular selection, in vitro growth, the generation of anti-infection and anti-neoplastic clones.
CELLULAR REPLACEMENT THERAPY
Reconstruction of a tissue by functional incorporation of transplanted stem cells.
CYTOMEGALOVIRUS
or cytomegalic virus is a very common virus of the herpes family. In healthy people the infection normally takes its course without symptoms. Once the virus has been contracted, it remains latent in the body and may become reactivated if the immune system is weakened. The virus can cause serious and even fatal complications in immune-compromised patients, e.g. patients who have undergone a transplant. Owing to improved diagnostic methods and more effective medication it is today possible to reduce the risks connected with a CMV infection.
COLLECTION
Occurs immediately after birth and refers to the process of collecting the umbilical-cord blood stem cells using a suitable collecting bag.
COMPATIBILITY
This refers to tissue compatibility and is usually identified by the scientific term HLA typing. The tissue type must be as compatible as possible between the donor and the recipient to minimise the risk of rejection.
CORD BLOOD
This is the blood contained in the umbilical cord and in the placenta at birth (about 100 ml) and contains the haematopoietic stem cells. The blood can be collected and donated to cord blood banks or be stored privately in tissue banks until the haematopoietic stem cells are needed for therapeutic purposes.
CRYOGENIC STORAGE
This is the process of freezing cord blood stem cells at very low temperatures using special techniques to ensure safe storage of the cells over long periods.
DIFFERENTIATION
Process of transforming a stem cell into a cell with a specific function.
EMBRYONIC STEM CELLS
Cells generated in vitro from the pluripotent cells that are found in the pre-gastrula embryo.
EMBRYO
Organism in the prenatal development phase comprised between fecundation and the complete formation of the organs (corresponding in humans to the first 8 weeks after fecundation).
HAEMOPOIETIC OR HAEMATOPOIETIC
Pertaining to the formation of blood or blood cells. A haematopoietic stem cell is a cell that can divide and produce blood cells and immune-system cells.
ENDOTHELIAL (STEM CELLS)
Cells that have the receiver CD133 and are progenitors of endothelial tissue. This is a single-layered epithelial coating tissue deriving from the embryonic mesoderm that covers the inner surface of the blood vessels and the heart (endocardium).
GMP
Good Manufacturing Practice. In other words, the good manufacturing practice to be followed when manufacturing drugs. These are methods and facilities that must be used to manufacture, treat and store a drug to ensure that it meets all safety, identification, quality and purity requirements.
GRAFT-VERSUS-HOST-DISEASE
Graft-versus-host-disease that occurs when the immunological cells of the transplanted tissue or organ attack the recipient’s organism.
HEPATITIS
General term to indicate inflammations of the liver that may damage the hepatic cells and cause liver malfunctions. Although hepatitis is generally viral in origin, it may also be caused by bacterial infections, autoimmune diseases or by the excessive consumption of alcohol. Viral hepatitis can take different forms, the most common being A, B and C.
HISTOCOMPATIBILITY
Compatibility between tissues. The cells of each individual carry on their surface molecules that characterise the cells and make them different from those of other individuals. When these molecules come into contact with the immune system of different organisms they make the cells extraneous and thus subject to attack by the immune defences. All these molecules are part of the greater histocompatibility complex indicated by the acronym HLA (Human Leukocyte Antigens). This characteristic is of fundamental importance in the transplant of organs and tissues and in the transfusion of blood and its derivates. To ensure that the transplant is accepted and not rejected, for example, there must be histocompatibility between the recipient and the donor. In other words, the transplanted tissue must have histocompatibility molecules that are identical or at least very similar to the molecules on the cells of the recipient of the transplant. Hence, before each transplant or graft and also before all blood transfusions, the tissue must be typed (i.e. the nature of the molecules must be studied) of both the donor and the recipient of the tissue (see HLA typing). Apart from the field of organ and tissue transplants and of transfusions, the molecules of the HLA system are fundamentally important in mechanisms for recognising all the extraneous substances that come into contact with the organism.
HIV
Abbreviation of ‘human immunodeficiency virus’, the AIDS virus.
HLA TYPING
HLA stands for Human Leukocyte Antigens and is also known as the histocompatibility system. It consists of molecules that are located on the cell surface and act as antigens: when they come into contact with the immune system of another individual they are recognised as being extraneous and provoke an immune response. This examination is conducted to ascertain the compatibility of the stem cells of the child with its siblings or relatives.
HTA
The authority that ensures the implementation of the Human Tissue Act in the United Kingdom.
HTLV
Human T-lymphotropic virus Type I (HTLV-1) is a human RNA retrovirus transmitted through sexual contact, through the use of EV drugs, through blood transfusions and from the mother to the child through the mother’s milk.
HUMAN LEUCOCYTE ANTIGENS (HLA)
Analysis of the umbilical cord stem cells to identify the tissue types. These latter are similar to the blood types. For a person who receives cells or tissues from another subject, there has to be the strictest compatibility between tissues. The type of tissue is determined by the DNA. There are millions of possible types of tissue and a large bank of stem cells increases the possibility of finding a compatible sample.
INCUBATION TIME
The time that elapses between contagion (penetration of the pathogen into the body) and the appearance of the first symptoms.
INTERNATIONAL STANDARD ORGANISATION
International organisation for standardised management of systems and processes.
JACIE (acronym of Joint Accreditation Committee – ISCT & EBMT)
Non-profit association set up to ensure and accredit the quality of centres for sampling, processing and transplanting haematopoietic stem cells by means of a standardised international accreditation system.
LEUKAEMIA
This term refers to rather a heterogeneous group of tumours that develop from haematopoietic cells, characterised by grave alterations in the mechanisms that regulate the processes of cell synthesis and maturation. The cells of these neoplasms proliferate and accumulate initially in the bone marrow, before invading the spleen, the lymph nodes and finally the other organs.
LEUKOCYTES
White blood cells. White blood cells fall into three subcategories: granulocytes, lymphocytes and monocytes.
LYMPHOMAS
Lymphomas is a general term used to indicate a heterogeneous group of tumours originating from lymphocytes, which are the main cells of the immune system. From the lymph nodes the disease (which has many traits in common with leukaemia) can spread throughout the blood and/or lymph vessels to other lymph nodes or organs, which by be lymphatic (marrow, spleen, etc) or may be extra lymphatic (skin, lungs, central nervous system, stomach, liver, etc).
MESENCHYMAL STEM CELLS
Mesenchymal stem cells are found in bone marrow and in the umbilical cord and can specialise in bone, cartilage and tissues that are connected to them. They can also be induced to specialise in a wide range of other cells.
MULTIPOTENT STEM CELLS
They are the cord cells, marrow cells, peripheral blood cells and tissue-specific cells such as epithelial cells and adipose cells that are able to specialise only in certain types of cell.
PLURIPOTENT STEM CELLS
All the cell lines of an organism (embryonic cells, foetal cells and amniotic fluid cells) that can specialise in all the types of cell that are found in an adult but not in cells that make up extra embryonic tissues.
PROCESSING
Process by which the umbilical cord stem cells are extracted from the blood, counted, analysed and frozen for long-term storage.
PERIPHERAL BLOOD
This is the blood that circulates in a human being’s veins and arteries; it is the blood that is outside the haematopoietic organs.
REGENERATIVE MEDICINE
Branch of medicine that will in future enable damaged cells and tissue in the human body to be repaired or regenerated.
SYPHILIS
Sexually transmitted disease that is caused by bacteria, which develops through different stages that are accompanied by different symptoms (e.g. lesions, migraine, fever, disturbances of the nervous system).
SOMATIC STEM CELLS
Non-specialised cells that are distinguishable from specialised cells of a specific tissue and are mainly multipotent. They are currently used to treat over seventy diseases and pathologies.
STEM CELLULARITY
Characteristic of different stem cells of being governed by common mechanisms and genes.
STEM CELLS
These are cells that can divide several times to generate identical copies of themselves or to create specialised cells able to perform particular tasks such as, for example, generating cells of blood, bone or liver. Stem cells are also known as ‘specialist’ or ‘clean’ stem cells owing to their capacity to transform themselves into a large number of cell types.
THALASSAEMIA
Generic term for genetic disturbances in haemoglobin synthesis that may cause more or less pronounced forms of anaemia. This disease is found mainly in populations bordering the Mediterranean and in the Middle East.
TISSUE
Complex of cell structures that form the organs. Four basic groups of tissue are distinguished on the basis of morphological, embryological and functional criteria: connective tissue; epithelial or coating tissue; muscular or contractile tissue; nervous tissue. These tissue are distinguished from one another during embryonic development by the germ layers.
TISSUE BANK
Institution in which (human) tissue can be stored for medical use (transplantation).
TISSUE ENGINEERING
The term tissue engineering defines procedures for regenerating tissues of the human body by sowing cells on scaffolds of appropriate biocompatible and biodegradable materials.
TISSUE STEM CELLS
They derive from or reside in a somatic or foetal tissue. They replace or repair certain tissues throughout the life cycle
TOTIPOTENT STEM CELLS
These are stem cells that are able to give rise to all types of cell, including those of the embryonic appendages.
TRANSPLANTATION
This is the removal of cells, tissue or organs for therapeutic use for the benefit of the donor or of another person.
ALLOGENEIC TRANSPLANT
In an allogeneic transplant the stem cells are donated by one person and are transplanted in another person for therapeutic purposes.
AUTOLOGOUS TRANSPLANT
In an autologous transplant the stem cells are transplanted in the same person from which they were removed for therapeutic purposes.
UNIPOTENT STEM CELLS
These are stem cells that can generally generate only one type of specialised cell.
UNITS
Stem cells taken from the umbilical cord should strictly speaking be described as ‘umbilical cord stem cell units.
