Researchers at the National Cancer Institute, a part of the National Institutes of Health find out a new approach to generate a power packed anti-tumor response in mice, by stimulating immune cells anti cancer activity.
This therapy, in which mice received CD8+ T memory stem cells together with a tumor vaccine and an immune system stimulant known as interleukin 2, improved the survival of treated mice compared with similar treatment using other types of memory T cells.
Researchers have found in their study that T lymphocytes called CD8+ memory stem cells, were capable of mediating strong anti-tumor immune response. These potent cells were generated in the laboratory by stimulating anti-tumor T cells in the presence of drugs designed to mimic an important signaling pathway called Wnt, which describes a complex network of proteins whose interactions are essential during development and stem cell maintenance.
T lymphocytes acquired stem cell-like properties of multipotency and self renewal; that is, they generated differentiating daughter cells while regenerating themselves when transferred back to mice from the lab. These stem cell-like qualities enabled tiny numbers of T cells (about 40,000 cells) to trigger the destruction of large melanoma tumors (containing about one billion malignant cells).
Lead author of the study Nicholas P. Restifo, an investigator in the Surgery Branch at the Center for Cancer Research, claims about the superiority of the new category of lymphocytes than the T cells used in earlier studies. He point out that the new category have the enhanced ability to renew themselves, to proliferate, to differentiate and ultimately to kill tumor cells.
The therapy consists of CD8+ T memory stem cells together with a tumor vaccine and an immune system stimulant known as interleukin 2. It is observed this combined approach can improved the the survival of treated mice compared with similar treatment using other types of memory T cells.
For further information regarding this study see Nature medicine online June 14, 2009.