Stem cell transplantation is now used worldwide in the treatment of any malignant and non-malignant hematologic conditions like auto immune diseases and in the treatment of various solid tumors. Every year, many hundreds of patients around the world receive an autologous or allogeneic transplant procedure, and the numbers have increased vastly.
Hematopoietic stem cell transplantation and cellular therapy (Regenerative Medicine) are rapidly developing, highly effective modalities of treatment for a broad range of hematologic, immunologic, metabolic and malignant diseases.
For many disorders, hematopoietic transplantation is potentially curative for what would otherwise be fatal diseases.
Hematopoietic transplantation is the most established form of cellular therapy and is a cornerstone of treatment for a broad range of hematologic malignancies.
This form of therapy consist in the bone marrow derived stem cells use, and it is possible obtain these cells directly from bone marrow or from peripheral blood through a procedure named apheresis.
Hematopoietic stem cell transplantation is still a relatively new treatmentmodality, having been used clinically only since the 1970s. Astime has passed, many changes and refinements have been introduced to improve the therapies. The patient population to which these techniques are applicable hasalso changed and enlarged as treatment has become safer, with theintroduction of improved blood product support, antibiotics and betterimmunosuppressant.
The 1990s were a period of rapid development in stem cell transplantation (SCT). Recombinantgrowth factors (G-CSF) had become available, which could be used to speed upwhite cell recovery after transplantation, therebyshortening the length of hospital stay. The use of peripheral bloodstem cells (PBSC) mobilized into the blood by G-CSF virtuallyreplaced the use of bone marrow for transplantation, avoiding the needfor a general anesthetic and arguably resulting in more rapid myeloidreconstitution so that it even became feasible to undertake autologousPBSC transplants on an outpatient basis, provided that medical backupwas near at hand.
It can be anticipated that stem cell transplantation procedures willcontinue to become safer, thereby allowing us to safely extend curativetreatments to elderly patients, and many other people with different pathologies.
Cellular components of the transplant:
Our current knowledge ofstem cell transplantation (SCT) biologyderives from a vast body of experimental data extending back morethan 50 years.
Transplants contain a variety of cell types but the hematopoietic stemcells (HSC), conveniently identified by the CD34 surface antigen andCD3+ T-lymphocytes, responsible for immunologic memory, are themost important because they can self-replicate and survive a lifetime in the person. Cells within the CD34 compartment establish lifelonghematopoiesis and regenerate an entire immune system.
In recent years, there has been much interest in the fact that SCT contain precursors of cells able to develop into non-hematopoieticcells such as pulmonary cells,angiocytes, endothelial cells, fibroblasts, neurons, heart cells and muscle cells. These facts allow the treatment of many diseases in those body areas.
Three transplant stem cell sources are in current use: bone marrow(BM), mobilized peripheral blood stem cells (PBSC) and umbilicalcord blood (UCB). These sources differ considerably both quantitativelyand qualitatively, and our Apheresis and Regenerative Medicine Unit only useBM and PBSC from the own patient body.
Cure of disease by stem cell transplantation
Advances in stem cell biology and immunology have greatly broadened the application of autologous SCT as acurative approach for a wide range of malignant and non-malignant,genetic and acquired disorders. Broadly, SCT has been used asa means of normalizing hematopoietic function, repairing no hematopoieticstates or for its immunologic functions.
Stem Cells used in the treatment of Lung Disease.
The lung is a complex organ with limited regenerativecapacity. Local stem cells, with the capacityfor unlimited self-renewal and the productionof more committed progenitors, have long beenthought of as central to the repair and regenerationprocesses of various organs. However, this endogenous repair in the lung is insufficient to preventthe many progressive respiratory diseases.
Many series of exciting reports over the last 5 to 10 years have demonstrated that adult bone marrow-derived stem cells may have more plasticity and are able to differentiate
into bronchial and alveolar epithelium, vascular endothelium, and interstitial cell types, makingthem prime candidates for lung repair.
Stem cells have a multitude of clinical implicationsin the lung. The realization that adult
bone marrow stem cells contribute to the repairof lung injury allows this avenue to be manipulatedand augmented in human diseases. Treatment bycell therapy could be envisaged for acute disorderssuch as Acute Respiratory Distress Syndrome, or more chronic disorders such asemphysema, chronic obstructive pulmonary disease (COPD) and lung fibrosis (CHEST 2007; 132:279–285).