生物谷报道：美国德州大学西南医学中心的生物医药专家和德州大学达拉斯分校的纳米技术专家正在试验一种治疗癌症的新方法，他们把能够识别癌细胞的抗体分子连接到微小的碳纳米管上面，在近红外光照射下，碳纳米管会发热，把癌细胞杀死。相关研究结果发表在最新一期的《国家科学院院刊》（PNAS）上。
在此项研究中，研究人员将针对淋巴肿瘤细胞特定靶位的单科隆抗体涂覆在微小的碳纳米管上。单科隆抗体是一种能黏结癌细胞的生物大分子，碳纳米管是由石墨碳原子组成的非常细小的圆筒，当遇到近红外光时会产生热量。近红外光可以穿透人体组织内部达1.5英寸（3.8厘米），人的肉眼虽看不到它，但夜视仪可以捕捉到它，电视机遥控器也是通过近红外光来发出控制信号的。
在淋巴癌细胞培养皿中，涂覆有抗体的碳纳米管黏附在癌细胞表面，当它们暴露在近红外光下时，碳纳米管开始加热，产生的热量足以把癌细胞“煮”死。而当涂覆的抗体与淋巴肿瘤细胞无关时，碳纳米管既不会黏附到肿瘤细胞上，也不会杀死它们。
该论文的作者之一，德州大学西南医学中心癌症和免疫生物学中心主任艾伦·维特塔博士认为，这项研究的引人之处在于使用近红外光来产生过高热，因为人体活组织对近红外范围内的辐射吸收较弱，而一旦碳纳米管黏附到肿瘤细胞上，来自外部的近红外光就可以安全地穿过正常组织，杀死肿瘤细胞。维特塔指出，这项研究证明，在实验室中可以专一地杀死癌细胞。但即便如此，在将这种新的治疗方法推广到临床研究以前，还有许多工作要做。
目前，有多个研究小组都在从事利用碳纳米管加热来杀死癌细胞的研究。维特塔的研究第一次证明，无论是抗体、还是碳纳米管，都保持了各自的物理特性和功能，那就是定向黏结到靶位细胞并且杀死它们。（生物谷www.bioon.com）
生物谷推荐原始出处：
PNAS，doi：10.1073/pnas.0803557105，Pavitra Chakravarty，Ellen S. Vitetta
Thermal ablation of tumor cells with antibody-functionalized single-walled carbon nanotubes
Pavitra Chakravarty*,, Radu Marches*,, Neil S. Zimmerman, Austin D.-E. Swafford, Pooja Bajaj¶, Inga H. Musselman¶,||, Paul Pantano¶,||, Rockford K. Draper,¶,||, and Ellen S. Vitetta*,**
*The Cancer Immunobiology Center, University of Texas Southwestern Medical Center, Dallas, TX 75390; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139; and ||The Alan G. MacDiarmid NanoTech Institute and Departments of Molecular and Cell Biology and ¶Chemistry, University of Texas at Dallas, Richardson, TX 75080
Contributed by Ellen S. Vitetta, April 11, 2008 (sent for review April 1, 2008)
Abstract
Single-walled carbon nanotubes (CNTs) emit heat when they absorb energy from near-infrared (NIR) light. Tissue is relatively transparent to NIR, which suggests that targeting CNTs to tumor cells, followed by noninvasive exposure to NIR light, will ablate tumors within the range of NIR. In this study, we demonstrate the specific binding of antibody-coupled CNTs to tumor cells in vitro, followed by their highly specific ablation with NIR light. Biotinylated polar lipids were used to prepare stable, biocompatible, noncytotoxic CNT dispersions that were then attached to one of two different neutralite avidin-derivatized mAbs directed against either human CD22 or CD25. CD22+CD25– Daudi cells bound only CNTs coupled to the anti-CD22 mAb; CD22–CD25+ activated peripheral blood mononuclear cells bound only to the CNTs coupled to the anti-CD25 mAb. Most importantly, only the specifically targeted cells were killed after exposure to NIR light.
