US scientists create HIV-resistant cells
Posted on Saturday, 3rd July 2010
American scientists have created HIV-resistant cells that could one day pave the way for controlling the virus without using harsh anti-retroviral drugs.
Scientists at the Keck School of Medicine, at the University of Southern California, used mice to test the cells that target one of the two "gateway" molecules that the Human Immunodeficiency Virus (HIV) uses to enter human cells, Meghan Lewit, spokeswoman for the team of researchers, said.
The researchers modified blood stem cells to make them resistant to HIV and then transplanted them into the mice, enabling the rodents to control the infection.
If the approach can be applied to humans, it could enable a long-term generation of HIV-resistant cells in the body, providing the potential for the patient's cells to suppress HIV, Lewit said.
"This hybrid gene and stem cell therapy show that it is possible to create HIV-resistant immune cells that can eventually win the battle against HIV," Paula Cannon, principal investigator and associate professor of molecular microbiology and immunology, was quoted as saying by Xinhua.
"We've done it at the scale of a mouse, and the challenge now is to see if this can be done at the scale of a human patient."
"The strategy arose from the observation that people with a mutation in a gene called CCR5 are naturally resistant to infection with the most common strains of HIV and do not develop AIDS," Lewit said.
Researchers used enzymes to knock out the CCR5 gene in human blood stem cells, and then transplanted the modified stem cells into mice, Lewit said.
The cells developed into mature cells of the human immune system, including the T cells that HIV infects. And when they infected the mice with HIV, the animals were able to maintain normal levels of the human T cells and suppress HIV.
"By engineering CCR5-deficient stem cells, we may allow a patient to produce HIV-resistant cells in all of the cell types that the virus infects, and for long periods of time," Cannon said.
"If successful, it could one day allow patients to control their HIV without needing to take anti-retroviral drugs."