A new immunotherapeutic approach to the treatment of brain cancer
Scientists at Duke University Medical Center, working under the leadership of Dr. John H. Sampson, have created a deadly weapon that destroys brain tumors in mice without affecting healthy tissues – an artificial protein consisting of two antibodies that "attaches" T-lymphocytes to cancer cells.
According to Sampson, the work carried out brings to life a somewhat outdated concept, according to which exposure to tumor-specific antigens is the most effective method of cancer treatment that does not have toxicity to the body as a whole. He and his colleagues decided to apply an immunological approach to the treatment of brain tumors, especially those that are poorly treatable. Despite surgical interventions, as well as chemo- and radiotherapy, glioblastomas usually lead to a fatal outcome, while the median survival rate of such patients is only 15 months.
Immunotherapeutic approaches, which consist in launching immune reactions selectively directed against tumors, have already demonstrated some success in the treatment of brain tumors and other organs, but their introduction into clinical practice has proved to be very problematic. One of the reasons for this is the difficulties with the introduction of therapeutic doses of drugs, and the second is the development of side effects manifested by the attack of the immune system on healthy organs and tissues.
To overcome these problems, researchers have created a kind of "adapter" – an artificial double antibody, called BiTE – bispecific T-cell engager, a bispecific activator of T cells (the word "engage" in English has a lot of meanings, including the military it is the command "fire"). The molecule of this protein consists of two parts, one of which binds to the antigen – EGFRvIII protein present only on the surface of tumor cells, and the second – to CD3 surface proteins specific for T-limophocytes, triggering a selective immune response.
In six out of eight mice with brain tumors, systemic (intravenous) administration of BiTE led to a complete cure.
In the near future, the authors plan to evaluate the effectiveness of the developed approach in clinical trials, as well as to study the interaction with traditional methods of treating malignant tumors, such as chemo- and radiotherapy.
Article by Bryan D. Choi et al. Systematic administration of a bispecific antibody targeting EGFRvIII successfully treats intracerebral glioma is published in the journal Proceedings of the National Academy of Sciences.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Duke University Medical Center:
New Immune Therapy Successfully Treats Brain Tumors in Mice.
20.12.2012