[Zhao, Yuliang] Chinese Acad Sci, Inst High Energy Phys, Key Lab Nucl Analyt Tech, Beijing 100049, Peoples R China
; [Chen, Chunying] Natl Ctr Nanosci & Technol China, CAS Key Lab Biol Effects Nanomat & Nanosafety, Beijing 100190, Peoples R China
Publications concerning the mechanism of biological activity, especially the immunological mechanism of C-60(OH)(20) nanoparticles, are relatively limited. However, the structure and characteristics of this carbon allotrope have been widely investigated. In this paper, we have demonstrated that water-soluble C-60(OH)(20) nanoparticles have an efficient anti-tumor activity in vivo, and show specific immunomodulatory effects to the immune cells, such as T cells and macrophages, both in vivo and in vitro. For example, C-60(OH)(20) nanoparticles can increase the production of T-helper cell type 1 (Th1) cytokines (IL-2, IFN-gamma and TNF-alpha), and decrease the production of Th2 cytokines (IL-4, IL-5 and IL-6) in serum samples. On the other hand, C-60(OH)(20) nanoparticles show almost no adverse effect to the viability of immune cells in vitro but stimulate the immune cells to release more cytokines, in particular TNF-alpha, which plays a key role in the cellular immune process to help eliminate abnormal cells. TNF-alpha production increased almost three-fold in treated T lymphocytes and macrophages. Accordingly, we conclude that C-60(OH)(20) nanoparticles have an efficient anti-tumor activity and this effect is associated with an increased CD4+/CD8+ lymphocyte ratio and the enhancement of TNF-alpha production. The data suggest that C-60(OH)(20) nanoparticles can improve the immune response to help to scavenge and kill tumor cells.