Jan 3, 2013 2:00 PM by Mary Elizabeth Dallas
THURSDAY, Jan. 3 (HealthDay News) -- Stem cell technology may one day give new life to tired immune cells so they can battle diseases such as HIV and cancer more effectively, two new studies suggest.
Scientists in Japan used old immune T-cells and regenerated them into T-cells that multiplied in greater numbers, had longer lifespans and showed a greater ability to target diseased cells. The finding could lead to more effective immune therapies, the researchers said.
Both reports were published in the Jan. 4 issue of the journal Cell Stem Cell.
"The system we established provides 'young and active' T-cells for adoptive immunotherapy against viral infection or cancers," study senior author Dr. Hiromitsu Nakauchi, of the University of Tokyo, said in a journal news release.
In one study, researchers transformed mature T-cells from an HIV-infected patient into pluripotent stem cells, a type of stem cell that has the ability to differentiate into nearly any type of cell in the body. In a second study, researchers used T-cells from a patient with melanoma, a particularly deadly type of skin cancer. In both cases, the researchers helped the pluripotent stem cells differentiate back into T-cells.
The good news was that these "rejuvenated" immune cells were an improvement on the original T-cells, the researchers noted.
The HIV patient's T-cells had an unlimited lifespan and long caps on the ends of their chromosomes, which protected them from aging.
Meanwhile, the T-cells from the patient with melanoma were able to recognize the protein commonly expressed in this type of cancer.
"The next step we are going to do is examine whether these regenerated T-cells can selectively kill tumor cells but not other healthy tissues. If such cells are developed, these cells might be directly applied to patients," study senior author Dr. Hiroshi Kawamoto, of the RIKEN Research Center for Allergy and Immunology in Yokohama City, Japan, said in the news release. "This could be realized in the not-so-distant future."
The U.S. National Institute of Allergy and Infectious Diseases has more on the immune system.