Gene transfer into hematopoietic stem cells

Article Abstract:

Since the advent of genetic engineering, medical researchers have speculated about the possibility of gene therapy - the introduction of normal genes into genetically deficient human tissues. Blood cells are the most promising candidates to benefit from this type of therapy. Blood may, of course, be removed from the patient, manipulated, and then returned with a minimum of risk. Similarly, the bone marrow, which is the progenitor of blood cells, may also be removed and replaced. Gene therapy of bone marrow cells is especially appealing; if the required gene could be introduced into the stem cells in the bone marrow, then the marrow would continue to produce healthy blood cells, presumably for the life of the patient. One example of a disease which might be successfully treated with this approach is sickle cell anemia. If normal hemoglobin genes could be introduced into the progenitors of the red blood cells, then as the bone marrow cells divided and differentiated, the patient would enjoy a supply of healthy red blood cells containing normal hemoglobin. Experiments in mice have shown that this is possible. However, the technical obstacles preventing the application of the method to human disease remain formidable. Generally, the gene desired for transfer must be included within a recombinant retrovirus. It is the retrovirus which actually accomplishes the work of inserting the gene into the host genome after the cell is entered. Of course, it is necessary that the retrovirus not be able to reproduce and cause infections, a problem which has not yet been solved. Furthermore, when experiments have been conducted in primates rather than mice, it has proved difficult to obtain high efficiencies. For example, using recombinant viruses to transfer genes into rhesus monkey cells, it has been possible to get expression of the transferred gene in only 1 to 5 percent of the blood cells. While the results of the research are very encouraging, and seem to indicate that gene transfer therapy is indeed possible, much development is required before the technique can be routinely applied to human genetic disease. (Consumer Summary produced by Reliance Medical Information, Inc.)

Research, Usage, Genetic aspects, Gene therapy, Genetic engineering, Hematopoietic stem cells

---

Opening remarks/keynote address

Article Abstract:

On August 31, 1990, the American Cancer Society hosted a symposium to bring together researchers in the field of hematopoietic growth factors. These hematopoietic growth factors play a role in stimulating the development of blood cells. The hematopoietic growth factors consist of a variety of different proteins; not only does each have a special job, but each also interacts with and affects the others in a complex fashion. Furthermore, there is some overlap in the function of these factors. For example, granulocytes, a type of white blood cell, are stimulated by the granulocyte colony-stimulating factor G-CSF. Similarly, macrophages are produced as a result of stimulation by macrophage colony-stimulating factor, M-CSF. However, there exists a granulocyte-macrophage colony-stimulating factor GM-CSF, which stimulates both. Both cell types are also stimulated by interleukin-3. These four substances can also induce the expression of interleukin-6 (IL-6). IL-6 does not stimulate the formation of colonies of these cells, but does stimulate the differentiation of primitive cells to differentiate into fully mature, functioning granulocytes, macrophages, and megakaryocytes. Why all this complexity? The author suggests that the existence of many factors with complex interactions may have been beneficial during the course of evolution. The complex interactions could adapt to changing requirements, and the disruption of any one part would not halt the overall physiological system. As more knowledge accumulates about the functions and interactions of the hematopoietic growth factors, new opportunities for therapeutic intervention are likely to arise. At present, the most successful clinical application of hematopoietic growth factors is the use of erythropoietin to restore red blood cell production in patients with severe kidney disease. Researchers are also evaluating these factors for speeding the recovery of the bone marrow in patients undergoing chemotherapy for cancer. Further uses will no doubt emerge with further research. (Consumer Summary produced by Reliance Medical Information, Inc.)

Conferences, meetings and seminars, Hematopoiesis, Hematopoietic agents, Colony-stimulating factors (Physiology), Colony-stimulating factors, Interleukin-3

---

Similar abstracts:

• Abstracts: The control of growth and differentiation in normal and leukemic blood cells. Acute respiratory failure and pulmonary thrombosis in leukemic children
• Abstracts: A clinical trial of two parenteral nutrition solutions in neonates. Pupillary diameter and reaction to light in preterm neonates
• Abstracts: A century of home parenteral nutrition for Crohn's disease. Nutritional support in surgical practice: part 2
• Abstracts: The effects of iodoprophylaxis on thyroid size during pregnancy. part 2 Activity of hepatic enzymes from week sixteen of pregnancy
• Abstracts: Lactose maldigestion and milk intolerance in healthy Greek schoolchildren. part 2 Biochemical evidence suggestive of suboptimal zinc and vitamin A status in schoolchildren in Northeast Thailand

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.