INDUCED pluripotent stem (iPS) cells could potentially be used to vaccinate people against cancer, according to researchers from Stanford University, California, USA. This follows a study in which the progression of cancer cells was prevented or slowed down when iPS cells were injected into mice, priming the immune system to fight the tumours.
Mouse Model
In the study, mice models were injected once a week over a 4-week period with different solutions. In one group, the mice received a control solution; another was given genetically matching iPS cells that had been irradiated; a third received an adjuvant; and a final group was injected with a combination of irradiated iPS cells and adjuvant. A mouse breast cancer cell line was injected into the mice to investigate the growth of the tumours.
Effective iPS Cells
Tumours of the breast cancer cells were developed at the injection site in all mice 1 week following the transplantation. In 7 out of 10 mice vaccinated with iPS cells plus the adjuvant, the tumours shrank in size, and two of these mice were able to completely reject the cancer cells, enabling them to live for over a year after the tumour transplantation. This was in stark contrast to the control groups, in which the tumours grew robustly. Similar findings were made in mice transplanted with a mouse melanoma and mesothelioma cell line.
Additionally, it was observed that T cells from vaccinated mice slowed the growth of breast cancer cells in unvaccinated mice; these T cells showed they recognised epitopes shared between breast cancer and iPS cells because they also blocked the growth of teratomas in mice receiving non-irradiated iPS cells.
Powerful Approach
“This approach is particularly powerful because it allows us to expose the immune system to many different cancer epitopes simultaneously,” explained lead author Dr Nigel Kooreman. “Once activated, the immune system is on alert to target cancers as they develop throughout the body.”
Vaccination Potential
The team believe that this approach could be used to vaccinate people against the development of cancer in the future. The next stage of research is to test the method in human cancers and immune cells in a laboratory setting.
James Coker, Reporter
For the source and further information about the study, click here.
