Two groups in Japan have reprogrammed cells that fight HIV and cancer, boosting the number and lifespan of the cells.

The body's immune system makes T cells that target viruses and cancer, but the pool of these cells quickly becomes exhausted. Shin Kaneko and Hiromitsu Nakauchi at the University of Tokyo and their colleagues took a group of HIV-specific T cells from a person with HIV. They reprogrammed the cells into stem cells, and then added key growth factors so that the stem cells developed into the original type of T cell. The rejuvenated cells retained their ability to target HIV, had an enhanced capacity for proliferation and had longer telomeres, or caps on the end of their chromosomes, suggesting a longer lifespan.

Hiroshi Kawamoto at the RIKEN Research Center for Allergy and Immunology in Yokohama and his colleagues used a similar approach to reprogram T cells specific to melanoma. The reprogrammed T cells could still recognize a protein commonly found on the surface of melanoma cells, and were present in greater numbers than they had been in the original population.

Cell Stem Cell 12, 114–126; 31–36 (2013)