الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Bone marrow transplantation (BMT) is a procedure that transplant healthy marrow which involves intravenous infusion of hematopoietic stem cells into a conditioned recipient whose bone marrow is not working properly. This therapeutic procedure reestablish marrow. BMT triggers a compromised state of multiple organs and tissues as well as sever immune depression which predispose to systemic infections due to associated treatment with chemotherapy, radiotherapy and the use of hepatotoxic or nephrotoxic drugs. The first documented human bone marrow transplantation was attempted in 1939, when a woman with gold-induced aplasia was given marrow intravenously from a brother with identical blood group antigens, but the transplant was not successful and the patient died five days later. A Nobel prize in medicine was awarded to E. Donnal Thomas, the work of Thomas and his colleagues led to the first successful allogenic transplantation in the late 1960s and the gradual acceptance of this therapy was during the 1970s. Discovery of the human leukocyte antigen (HLA) system and development of histocompatibility typing methods in the 1960s led to a new Phase of marrow transplantation. The first successful marrow transplants were in children with sever combined immune deficiency (SCID) performed in 1968. By the end of 1992, more than 50.000 patients had been treated with BMT from allogenic and syngeneic donors. BMT is classified according to the genetic relation of the donor and the host into three types Autologous BMT, Allogeneic BMT, and Syngeneic BMT. Autologous BMT (ABMT) is the use of patients own marrow. Allogeneic BMT is marrow transplantation between genetically non-identical individual of the same species. Allogeneic transplants are either MHC matched, if all the MHC loci are shared or MHC mismatched, if there are any histocompatibility differences. Also, it may be related (sibling or family member) or unrelated transplant. Syngeneic BMT is a marrow transplant between genetically identical members of the same species i.e. identical twins. They are identical at all major and minor transplantation loci. BMT also classified according to source of stem cells into four types: Bone marrow stem cells, Peripheral blood stem cells (PBSC), Umbilical cord blood (UCB), and Fetal liver. The process of BMT should be termed hematopoietic stem cell transplantation, because the stem cells responsible for reconstituting the immune system can now be harvested directly from the circulation. Currently, most transplants deliver peripheral-blood–mobilized stem cells and not cells harvested directly from the BM by aspiration. Another source of stem cells used currently is the umbilical cord. Peripheral blood stem cells are now the most common source of stem cells for allogeneic HSCT. For allo-BMT, PBSC collected from healthy donors given granulocyte colony-stimulating factor (G-CSF) are now often used as an alternative to bone marrow. The use of PBSC when compared to BM may lead to a reduction in relapse rates after transplantation, due to an enhanced graft-versus-tumor effect. An overall improvement in survival has not been demonstrated, however, there may be a trend towards better outcomes after PBSCT in patients with high-risk disease. Advantage of USB transplant includes; easy and safety of hematopoietic stem cells collection, prompt availability, low risk of viral contamination and at least in recipients of HLA-compatible sibling graft, reduced GVHD. Cord blood for transplantation is collected from the umbilical cord and placenta after a baby is delivered. Donated cord blood that meets requirements is frozen and stored at a cord blood bank for future use.Cord blood banks established worldwide as a result of the increased use of umbilical cord blood (UCB) transplantation. The outcomes of this procedure relate to the cell dose of the UCB unit and the UCB collection. UCB has been used as a source of hematopoietic progenitor cells for the treatment of several diseases affecting children and, more recently, adult patients. To date nearly 14,000 of umbilical cord blood transplants have been performed worldwide in pediatric and adult patients. Haematopoietic stem-cell transplantation is used to treat many hematological cancers, but is limited by the lack of suitable bone-marrow donors, the risk of graft-versus-host disease (GVHD) and slow immune reconstitution. Umbilical-cord blood is an alternative source of haematopoietic stem cells that has recently been tested in both child and adult cancer patients. These studies have identified several advantages to umbilical-cord cell transplantation, including a lower incidence of GVHD. Umbilical-cord blood is therefore a promising alternative to bone-marrow-derived stem cells. Umbilical cord blood has been used successfully in related transplants for both malignant and nonmalignant diseases. This research include the laboratory study of cells that separate them from the blood, bone marrow, and umbilical cord to identify the immunological and genetic specifications for each of them then the experience of these cells to experimental animals for the treatment of several diseases. Test research treatment for person in Egyptian universities and teaching hospitals still in the experimental stage. The cord blood bank is important step in this research. The cord bank started to appear in Egypt. Storing cord blood stem cells provides an assurance to deal with future critical conditions.