主页 > 医学信息 >
【medical-news】放疗有助于艾滋病治疗
Trials in mice show potential for other infectious diseases
BY ROBERT COOKE
Special to Newsday
November 14, 2006
By using nature's own homing devices to carry radioactive weapons, scientists find they can successfully attack and eliminate cells that have been invaded by microbes, including the virus that causes AIDS.
So far this intravenous treatment has been used only in mice, but it raises the possibility of a whole new approach to drug therapy for many infectious diseases. The homing devices - called monoclonal antibodies - can be specifically tailored to attack infected cells, apparently leaving normal cells untouched.
In a recent report in a new online journal, the Public Library of Science, researchers at Albert Einstein College of Medicine in the Bronx announced that a treatment called radioimmunotherapy successfully attacked HIV-infected cells in mice. This approach is sometimes used against cancer, but it is now being expanded to fight infectious diseases.
"This work introduces a new approach for treating many viral infections, from hepatitis C to ebola, in which viral proteins are expressed on the surface of infected cells," said Dr. Arturo Casadevall, at the Einstein medical center. "This study in mice supports the idea that radioimmunotherapy might help in treating people infected with HIV," the human immunodeficiency virus.
Indeed, what they saw was a dose-response effect: Giving more of the drug caused a greater response. The animals had first been injected with human white blood cells already infected by HIV, and the cells were killed by the radioactive treatment.
For these tests against HIV, the Einstein team created monoclonal antibodies, which are molecules that attach themselves to tiny signaling molecules on the surfaces of white blood cells infected by the virus. This fact - that infected cells display telltale surface markers - offers what doctors call an "exploitable difference" that can be targeted for treatment.
The cell-killing mechanism is radioactivity. Through laboratory manipulation, each antibody molecule is armed with a radioactive form of either bismuth or rhenium. After the armed antibodies are injected and reach their target cells, the radioactive element zaps the infected cells. While linked to the targets, the lethal subatomic particles emitted by the isotopes kill the cells by damaging internal mechanisms such as membranes and genes. Other infected cells in the neighborhood can also get killed.
This effect is brief; the bismuth loses half of its radioactive punch every half hour, while rhenium's "half life" is 17 hours. The bismuth emits weak alpha particles; rhenium emits beta particles. Both work at relatively short range.
The use of radioimmunotherapy is being pioneered by Dr. Ekaterina Dadachova, at Einstein. Her animal studies began five years ago, and infectious disease organisms tested include a fungus, bacteria, and now the HIV virus. Because the virus hides inside white blood cells, the treatment must be aimed at infected cells, not at the virus itself.
The doctors at Einstein said they saw no serious deleterious results from radioimmunotherapy in the mice.
According to Dr. Harris Goldstein, director of the Center for AIDS Research at the medical center, AIDS is so difficult to treat because the most effective drugs can block viral reproduction, and block HIV from infecting other cells, but the problem is to get at the remaining viruses that remain hidden inside cells.
"We currently have no way of eliminating the HIV-infected cells that make these infections chronic," even though the disease seems to be controlled, at least temporarily, by current drug treatments, Goldstein said. So the difficult problem is to eliminate these tiny "reservoirs," the cells from which disease can emerge even after years of control.
http://www.newsday.com/news/health/ny-hsdrug4974339nov14,0,6889293.story?coll=ny-health-print 本人已认领该文编译，48小时后若未提交译文，请其他战友自由认领。
最近翻译几篇类似的。 Radioactive therapy tested against HIV
Trials in mice show potential for other infectious diseases
BY ROBERT COOKE
Special to Newsday
November 14, 2006
By using nature's own homing devices to carry radioactive weapons, scientists find they can successfully attack and eliminate cells that have been invaded by microbes, including the virus that causes AIDS.
科学家最新发现利用携带放射性的天然导轨武器，能够成功的攻击和消灭被微生物侵入的细胞。这包括能导致AIDS的病毒。
So far this intravenous treatment has been used only in mice, but it raises the possibility of a whole new approach to drug therapy for many infectious diseases. The homing devices - called monoclonal antibodies - can be specifically tailored to attack infected cells, apparently leaving normal cells untouched.
阅读本文的人还阅读：
作者:admin@医学,生命科学 2011-05-24 17:14
医学,生命科学网