美國賓州著名的 Kimmel癌癥研究中心(Kimmel Cancer Center) ,，發(fā)展出一種新的方法，可以在體外大量的產(chǎn)生血液里的自然殺手細(xì)胞，然后搭配一項以抗癌單株抗體為主的癌癥治療策略,，居然大幅的增加了抗癌藥物的作用,。
主導(dǎo)這份研究計劃的 Takami Sato醫(yī)師，在四月份美國洛杉磯舉行的全美癌癥研究學(xué)會 (American Association for Cancer Research)年會中表示,，目前實驗室里的數(shù)據(jù),，證實把這種體外增殖成功的自然殺手細(xì)胞，和一個專一性辨識稱 HER2/neu蛋白質(zhì)的單株抗體加在一起,，可以有效的阻殺乳癌 (breast cancers)細(xì)胞的增生,。
先前的臨床分析數(shù)據(jù)證實，大約在四分之一的臨床乳癌檢體中,，可以發(fā)現(xiàn) HER2/neu蛋白質(zhì)有異?；罨默F(xiàn)象。
Sato 博士進一步解釋表示,，自然殺手細(xì)胞在身體里,，本來就具有毒殺腫瘤細(xì)胞的能力，不過一般來說,，罹患癌癥的病人,，其體內(nèi)的自然殺手細(xì)胞的濃度，都會有下降的跡象,，而剩余下來的殺手細(xì)胞,，也可能存在著辨識力不足的可能，如今如果可以在體外大量的增生殺手細(xì)胞,，再搭配原本具有專一性辨識,，稱為Herceptin 的單株抗體，那等于強化了自然殺手細(xì)胞的作用,， 失序的癌細(xì)胞當(dāng)然逃不過這樣的治療策略,。
(資料來源 : Bio.com)
英文原文：
Jefferson Researchers Boost Immune 'Killer Cells,' Increase Antibody Effectiveness Against Cancer
04/18/07 -- Researchers at the Kimmel Cancer Center at Jefferson in Philadelphia have devised a novel method to expand the number of immune system "natural killer (NK)" cells from blood cells outside the body. They have found that adding such cells to anti-cancer therapies involving monoclonal antibody drugs is more effective in killing cancer cells, and perhaps someday may improve treatments.
Reporting April 18, 2007 at the annual meeting of the American Association for Cancer Research in Los Angeles, scientists led by Takami Sato, M.D., K. Hasumi Associate Professor of Medical Oncology at Jefferson Medical College of Thomas Jefferson University showed in laboratory studies that adding such NK cells to a monoclonal antibody, Herceptin, which targets the HER2/neu protein on breast cancer cells, was more efficient at killing the cancer cells. The HER2/neu protein is expressed in approximately one-quarter of all breast cancers.
According to Dr. Sato, monoclonal antibodies help kill cancer cells by attaching to the cancer cell surface, in turn stimulating an outpouring of "effector" cells such as NK cells that attempt to neutralize the cancer. NK cells alone are often powerful cancer fighters, he notes, but NK cell function in cancer patients can be diminished, and chemotherapy can make things even worse.
Dr. Sato, international research study coordinator Mizue Terai, M.S., and their co-workers decided to try a different approach. They cultured peripheral blood mononuclear cells, which are a mixture of immune cells, including NK cells, for three weeks in the test tube with their novel technique. The resulting population of NK cells increased 500 to 1,000-fold. In subsequent experiments, they showed that the combination of NK cells and Herceptin was effective in killing HER2/neu-expressing breast cancer cells, though the effect depended on the amount of antibody.
They found that the expanded group of NK cells and antibody had little effect against breast cancer cells that did not express the HER2/neu protein.
"It [the results] doesn't mean that the antibody and the NK cells will cure the cancer," Dr. Sato notes, "but it shows that using an antibody that recognizes the cancer cell along with added NK cells can be very effective against the tumor."
The researchers also found that the monoclonal antibody Rituxan greatly enhanced the cancer cell-killing ability of the expanded NK cells against another cancer cell line, B-cell lymphoma cell line. Rituxan is typically used in combination with chemotherapy to treat patients with B-cell non-Hodgkin's lymphoma.
Dr. Sato says that the technique can be applied to "any cancer that has a monoclonal antibody available."
The team's next step is to test the effectiveness of the added NK cells in an animal model. The group is also in the process of starting an early phase clinical study.
Source: Thomas Jefferson University
