A new strategy for cancer immunotherapy
The fight against cancer is proposed to be conducted on two fronts
Asya Gorina, VestiResearchers from the Massachusetts Institute of Technology have developed a new method of cancer immunotherapy.
The essence of the technology is to combine the work of the two main branches of the immune system.
Previous attempts to use the power of the human immune system to fight malignant tumors have focused on two different strategies. Scientists either tried to stimulate T cells to fight cancer cells, or forced antibodies to attack tumors. However, none of these techniques has shown high efficiency.
The study conducted by a group of scientists from the Massachusetts Institute of Technology is based on combining these two techniques into one and combining their effectiveness in the fight against malignant tumors. Biochemists have developed a special modified molecule that directs both T cells and antibodies to destroy cancer.
It is believed that one of the many signaling molecules – cytokines, interleukin-2 (IL-2) is capable of causing both types of immune response, however, positive results have not yet been observed in experiments on model organisms.
Biochemists have found that the timing of IL-2 delivery plays a key role in the effectiveness of its action. Previous laboratory studies have shown that the molecule is able to significantly improve the effectiveness of the fight of natural killer cells against cancer cells when it comes to adding it to tumor cells in a Petri dish (then IL-2 is located in close proximity to the focus of the disease for a long time). However, the same molecule showed very low efficiency in the bloodstream – from here, the kidneys filter out IL-2 (as a foreign agent) for an hour, without giving an opportunity to launch an attack on cancer cells.
To overcome this difficulty, the researchers combined the IL-2 molecule with a part of the antibody molecule, allowing it to remain in the patient's bloodstream for a longer period of time with such a "cover". These modified compounds (Fc/IL-2) were tested on mice with severe melanoma (skin cancer). The results showed that all representatives of the main group had stopped tumor growth.
Diagram from the article in Cancer Cell – VM
Moreover, the researchers report in a press release that in 80-90% of mice, tumors disappeared altogether, and their immune system was able to destroy new cancer cells introduced into the body even a few months after the initial treatment (Recruiting the entire immune system to attack cancer).
As scientists explain, the IL-2 molecule itself is not the main weapon in the fight against tumors. It only creates a favorable environment for the coordinated work of T cells and antibodies.
"The immune response, initially caused by the work of antibodies, creates a special environment in the body that allows T cells to destroy tumors. In the absence of compound molecules, T cells are practically powerless in the fight against cancer," explains the study's lead author Dane Wittrup, professor of chemical engineering at the Massachusetts Institute of Technology.
Also during the study, the scientists found that T-cells were much more effective in destroying tumors when they were delivered to the body together with antibody-IL-2 molecules-compounds than when they were injected separately. Therefore, Wittrap and his colleagues believe that their work will help to create a new method that complements existing cancer treatment technologies based on the work of antibodies.
The team continues to study the properties of the IL-2 molecule and tries to further improve the effectiveness of the new treatment method. And the results of the completed study are presented in an article published in the journal Cancer Cell (Zhu et al., Synergistic Innate and Adaptive Immune Response to Combination Immunotherapy with Anti-Tumor Antigen Antibodies and Extended Serum Half-Life IL-2).
Portal "Eternal youth" http://vechnayamolodost.ru23.04.2015