As reported in the journal Nature Nanotechnology last year, the Yale scientists created the new cancer-fighting composite by attaching antigens and polymer nanoparticles to a bed of CNTs. The polymer nanoparticles contain magnetite and the T-cell growth factor interleukin-2 (IL-2). These carbon fiber nanotube-polymer particles (CNP) were then used to grow T-cells, which were magnetically separated from the CNPs, reintroduced into the study’s mice and shown to be effective in delaying melanoma tumor growth. The study authors say that the combination of the CNT high surface area and nanoparticles releasing a T-cell growth factor leads to quicker and greater expansion of T-cells outside the body for cancer immunotherapy.
“In repressing the body’s immune response, tumors are like a castle with a moat around it,” says Tarek M. Fahmy, associate professor of biomedical engineering and immunobiology at Yale University and the study’s principal investigator. “Our method recruits significantly more cells to the battle and arms them to become super killers.”
T-cells are typically grown on a variety of high surface area platforms that include magnetic and latex beads. However, these methods are too expensive and time consuming to be widely used, according to the researchers. Efficiencies in the new CNT therapy may change that. Fahmy and his colleagues used the CNTs to expand T-cells 200-fold over 14 days, while also using 1,000 times less IL-2 than other methods.
This efficiency is partially due to the unique and imperfect topology of nanotubes. Fahmy stresses that nanotubes provide a high surface area that is rich in surface defects. These structural gaps facilitate the absorption of proteins and nanoparticles, creating a structural environment similar to the body’s own T-cell producing lymph nodes. In other words, a good environment for T-cells to cluster and grow.