Today, tomorrow, learn English naturally. 天天自然学英语
Experimental vaccine reprograms cancer to launch immunotherapy attack
Scientists have developed a new type of cancer vaccine that shows promise in clearing out leukemia in mice. The technique involves reprogramming cancer cells into immune cells so that they can teach the immune system how to fight off the disease.
In a fair fight, our immune system would defeat cancer every time. But this dastardly disease doesn’t fight fair, instead using a range of underhanded tricks to evade detection. Immunotherapy is an emerging treatment that involves supercharging the immune system to better fight off cancer, with some very promising early results.
One of the most common forms of immunotherapy works by removing T cells from a patient, programming them to recognize specific cancer antigens, and setting them loose in the body to hunt down cancers with those antigens. The problem is, this requires a degree of guesswork in figuring out which antigens would be most useful for each patient.
So for the new study, scientists at Stanford Medicine developed a way to teach T cells to recognize a broader swathe of antigens, increasing the chances that a patient’s immune system would successfully attack their cancer. The trick is to convert cancer cells into macrophages, which are a type of antigen-presenting cell (APC) that teaches T cells what to look for.
“We hypothesized that maybe cancer cells reprogrammed into macrophage cells could stimulate T cells because those APCs carry all the antigens of the cancer cells they came from,” said Ravi Majeti, senior author of the study.
To test the idea, the researchers induced leukemia cells in mice to transform into APCs. And sure enough, the mice in the control group successfully cleared out their cancer. Better yet, the vaccine strategy seemed to work longer term to prevent the disease recurring.
“When we first saw the data showing clearance of the leukemia in the mice with working immune systems, we were blown away,” said Majeti. “We couldn’t believe it worked as well as it did. What’s more, we showed that the immune system remembered what these cells taught them. When we reintroduced cancer to these mice over 100 days after the initial tumor inoculation, they still had a strong immunological response that protected them.”
Next, the team tested the technique on mice with three different types of solid tumors – fibrosarcoma, breast cancer and bone cancer. The results weren’t quite as effective as in leukemia, but still showed positive effects.
And finally, the researchers experimented with cells taken from human patients. Sure enough, APCs derived from human leukemia cells seemed to be successful in teaching T cells from the same patient what to look for. That suggests that the method could eventually be applied to humans, but far more work still needs to be done.
“We showed that reprogrammed tumor cells could lead to a durable and systemic attack on the cancer in mice and a similar response with human patient immune cells,” said Majeti. “In the future we might be able to take out tumor cells, transform them into APCs and give them back to patients as a therapeutic cancer vaccine. Ultimately, we might be able to inject RNA into patients and transform enough cells to activate the immune system against cancer without having to take cells out first. That’s science fiction at this point, but that’s the direction we are interested in going.”
注释：
therapeutic: adj
表示" 治疗的"，means "relating to or involved in therapy"，如：Mourning can have a therapeutic function that we ignore at our peril.悲痛可以有一种治疗的功能，即让我们忽略我们的风险。
leukemia: n
表示" 白血病"，means "malignant neoplasm of blood-forming tissues"，如：A close friend of mine recently underwent tests for leukemia.我的一个好朋友最近接受了白血病测试。
dastardly: adj
表示"欺善怕恶的；"，means "despicably cowardly"，如：Who was involved in these dastardly deeds? 有谁参与这种龌龊事？
underhanded: adj
表示"卑鄙的；"，means "marked by deception"，如：I don't believe in getting what you want by underhanded methods.我认为以不光明的手法获取东西是不应该的.
supercharge: v
表示" 过份给与；"，means "increase or raise"，如：To make the most out of this free subliminal session to supercharge your self esteem, use it for 21 days without missing a day! 充分利用这个潜意识课程来为您的自尊心加油,连续使用21天，千万别间断！
antigen: n
表示" [医] 抗原"，如：It will become a tumor antigen.它会变成一种肿瘤抗原。
swathe: n; v
1. n表示"绷带"，means "=swath,an enveloping bandage"，如：The earthquake devastated a huge swath of Sichuan.地震摧毁了四川的一大片带状区域。
2. v表示"紧绑"，means "wrap in swaddling clothes"，如：His head was swathed in bandages.他的头用绷带缠着。
Macrophages：n
表示"巨噬细胞"，如：Clusters of lipid-laden macrophages are seen.可见到成簇的充满脂质的巨噬细胞。
hypothesize: v
表示" 假设"，means "o believe especially on uncertain or tentative grounds"，如：Similarly, one might also hypothesize that females, on the other hand, select toys that allow them to hone the skills they will one day need to nurture their young.同样地，我们也可以假定，雌性选择的玩具，可以让她们磨练照顾孩子的技巧，反正她们迟早会生养子女
inoculation：n
表示"接种疫苗"，means "taking a vaccine as a precaution against contracting a disease"，如：Have the baby have a diphtheria inoculation? 给孩子种白喉疫苗了吗?
immunological：adj
表示"免疫学的"，means "of or relating to immunology"，如：Is there data on the durability of immunological benefits? 有没有免疫稳定上的好处?
fibrosarcoma: n
表示" 纤维肉瘤"，如：The pathological characteristics of the tumors developed were similar to that of fibrosarcoma.且形成肿瘤的病理表现与纤维肉瘤的特征相一致。
immunotherapy: n
表示"免疫疗法"，means "therapy designed to produce immunity to a disease or to enhance resistance by the immune system"，如：Active specific immunotherapy(ASI) is a important way in tumor therapy. 研究认为,主动特异性免疫治疗是肿瘤治疗的主要发展方向之一。
中文简要说明：
史丹佛大学的研究团队利用「指导免疫细胞识别癌细胞特」的方式，开发了一种白血病疫苗，目前已进入初期的人体实验。他们相信同样的技术也可以应用在其他的癌症上。
新阿特拉斯(New Altas)报导，癌症，是正常细胞的异变，因此所有细胞都有癌化的可能。所幸我们有免疫系统，可以清除这些异变，才得以健康的生存。既然如此，为何还会罹患癌症？原来，如果在一场公平的战斗中，我们的免疫系统每次都会战胜癌症。但是癌症是卑鄙可耻的，它们演化出一系列欺骗的手段来逃避检测，蒙蔽了免疫系统。
因此，新一代的抗癌疗程，就是「重新训练免疫细胞」，更专业的说法是「免疫疗法」，这个新兴的技术在这几年取得了一些非常有希望的早期结果。
最常见的免疫疗法，是从患者体内取出T细胞，对它们进行改造，以识别特定的癌症抗原，然后将它们注回患者体内，由这些重新训练的特化T细胞去寻找癌症。但是，这种疗法是个人化的，无法广泛普及。
史丹佛大学医学院的科学家，则们开发了一种方法来指导免疫细胞去识别更广泛的癌细胞抗原。诀窍是将癌细胞转化为巨噬细胞的模样，巨噬细胞也是一种免疫细胞，并且是一种抗原呈递细胞 ( antigen-presenting cell ,APC)，可以指导会T细胞寻找什么。
研究员梅杰迪(Ravi Majeti)说：「我们将癌细胞重新改造为巨噬细胞，以刺激T细胞，因为这些 APC ，身上携带来自的癌细胞的所有抗原。」
这种情况就像是一名强盗洗新革面，还成为「警察教官」，由于他的犯罪经验丰富，他指导下的警察们，就对所有犯罪特征充份了解，打击罪犯的效率因此更高。
为了验证这个想法，研究人员成功的将小鼠的诱导白血病细胞转化为APC。在重新回小鼠身上后，果然！小鼠成功地清除了它们的癌症。更好的是，疫苗策略似乎可以长期有效地预防癌症复发。
梅杰迪说：「在小鼠抗癌成功后，相隔100多天，再把癌症因子重新注入小鼠时，小鼠没有发生癌症复发的情况，强烈的免疫反应再次击败癌症。」接下来，团队把相同的技术用到其他癌症（纤维肉瘤、乳腺癌和骨癌）的小鼠身上测试了该技术，结果不如白血病那么有效，但仍然有还算正向的效果。
最后，研究人员也对白血病志愿者身上进行了实验，果然！仍然有效果！源自人类白血病细胞的 APC，成功地教会了来其他的T细胞，以对抗身上的癌化白血球，这表明该技术可以应用于人类，但仍需要做更多的工作。
留言微信公众号《自然学英语LearnNaturally》，可咨询更多: