'Assassin cell' therapy to tackle HIVResearchers have developed a new "assassin cell" therapy for treating HIV HIV (Human Immunodeficiency Virus), either of two closely related retroviruses that invade T-helper lymphocytes and are responsible for AIDS. There are two types of HIV: HIV-1 and HIV-2. HIV-1 is responsible for the vast majority of AIDS in the United States. which involves engineering the patient's own immune system immune system Cells, cell products, organs, and structures of the body involved in the detection and destruction of foreign invaders, such as bacteria, viruses, and cancer cells. Immunity is based on the system's ability to launch a defense against such invaders. to fight the virus more effectively. The therapy – which has proved effective in laboratory tests using human cell cultures – will be tested in a clinical trial of 35 patients with advanced HIV infection that is due to start next summer. Efforts to find a traditional vaccine against HIV – the virus that causes Aids – have so far drawn a blank. "HIV mutates Mutates Undergoes a spontaneous change in the make-up of genes or chromosomes. Mentioned in: Antiretroviral Drugs so quickly," said Dr Bent Jakobsen at Adaptimmune, the company in Oxford that is developing the new approach. "Gradually it gets better and better at escaping the detection of the immune system." Jakobsen and his colleagues began to pursue a different approach after investigating a patient who had resisted his HIV infection particularly effectively. "When we tested the T cells T cells A type of white blood cell produced in the thymus gland. T cells are an important part of the immune system. Infants born with an underdeveloped or absent thymus do not have a normal level of T cells in their blood. from this patient, it looked as if he was responding to a number of those variants that normally escape the immune system," he said. T cells are components of the immune system that attack and destroy cells within the body that are infected in·fect tr.v. in·fect·ed, in·fect·ing, in·fects 1. To contaminate with a pathogenic microorganism or agent. 2. To communicate a pathogen or disease to. 3. To invade and produce infection in. . They recognise components of the virus – antigens – that are displayed on the outside of infected cells. In this patient, the T cell receptor The T cell receptor or TCR is a molecule found on the surface of T lymphocytes (or T cells) that is generally responsible for recognizing antigens bound to major histocompatibility complex (MHC) molecules. protein seemed particularly good at recognising HIV antigens. The team isolated the receptor protein receptor protein n. An intracellular protein or protein fraction having a high specific affinity for binding agents known to stimulate cellular activity, such as a steroid hormone or cyclic AMP. and then improved its ability to recognise HIV further by randomly mutating it. Treating patients will involve taking a blood sample and adding an engineered virus containing genes for the improved T cell receptor. The patient's own T cells then take up the genes and so are equipped with the improved receptor. These cells are then injected back into the patient. The result was a T cell receptor that binds to HIV 450 times more strongly. The study was published yesterday in Nature Medicine. "In the face of our engineered assassin cells, the virus will either die or be forced to change its disguises again, weakening itself along the way," said Prof Andy Sewell from Cardiff University Cardiff University (Welsh: Prifysgol Caerdydd) is a leading university located in the Cathays Park area of Cardiff, Wales. It received its Royal charter in 1883 and is a member of the Russell Group of Universities. It has an annual turnover of £315 million. . "Because the immune cells work so much better when they have this modified antigen receptor they can eliminate the virus. And the mutants that normally escape detection are also recognised and eliminated," Jakobsen said. "That's not to say that will happen in patients. HIV is incredibly difficult to deal with. But it does give hope that it will do much more than the immune system does against the virus." The search for a vaccine has not gone smoothly. Last year a major trial of an experimental vaccine developed by Merck was abandoned and during the summer work on another vaccine candidate was shelved. The clinical trial of 35 patients next summer will take place at the University of Pennsylvania (body, education) University of Pennsylvania - The home of ENIAC and Machiavelli. http://upenn.edu/. Address: Philadelphia, PA, USA. in Philadelphia. 
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