Artificial antigen-presenting cells stimulate immunity better than real ones
Dr. Tarek Fahmy and his graduate student Erin Steenblock from Yale University have developed the first ready-to-use artificial antigen-presenting particles that can be modified depending on the disease against which it is necessary to induce immunity. The authors believe that their proposed method will very soon take its place in clinical practice, since the new particles are made from a natural biodegradable polymer approved by the US Food and Drug Administration and used in the production of surgical suture material.
Cancer, various infections and autoimmune diseases respond to immunotherapy that activates the body's own antigen-specific T cells. To do this, the patient's immune cells are isolated from the blood, cultured together with cells that stimulate the activation and proliferation of antigen-specific T-lymphocytes, which are subsequently returned to the patient's bloodstream. (The processing of antigens and their presentation to various populations of lymphocytes is carried out by macrophages, B lymphocytes, dendritic and some other cells). The limitations of this procedure include the high cost and complexity of cell isolation, as well as the risk of side effects. In addition, to achieve a therapeutic effect, it is necessary to obtain a sufficient number of activated T-lymphocytes, which is often associated with certain problems.
The new method is devoid of all these disadvantages. The surface of each artificial antigen-presenting particle is covered with universal adapter molecules that serve as attachment sites for both antigens selected depending on the disease and for molecules that additionally activate the patient's T-lymphocytes.
Cytokines are placed inside the particle, the gradual release of which provides further stimulation of activated lymphocytes and their proliferation to amounts 45 times higher than the initial ones.
The image taken with a fluorescent microscope shows an artificial immunocompetent cell (a red ball) associated with activated T-lymphocytes. Scale division = 10 microns.
The authors hope that the safe and effective stimulation of the immune response to specific antigens provided by the introduction of such particles will soon form the basis of a new approach to immunotherapy of cancer and infectious diseases.
Portal "Eternal youth" www.vechnayamolodost.ru based on materials from Yale University
28.02.2008