January 29, 2013 A new gene therapy could make a person's CD4+
cells resistant to HIV -- a method that, if successful, would
eliminate the need for antiretroviral drugs for those living
with HIV, according to a new study conducted by researchers at
the Stanford University School of Medicine. HIV replicates by
infecting a person's CD4+ cells, which the virus enters through
the CCR5 receptor (or, in rare cases, the CXCR4 receptor) found
on the CD4+ cell surface. Inactivating these receptors would
block HIV from entering the cells. The study, led by Matthew
Porteus, M.D., an associate professor of pediatrics at Stanford,
follows in the footsteps of Sangamo BioSciences' ongoing
research using zinc finger nucleases to artificially disrupt the
CCR5 receptor on the surface of CD4+ cells. Porteus and his team
take that approach and go one step further. They used the same
nuclease to zero in on an undamaged section of the CCR5
receptor's DNA. They created a break in the sequence and, in a
feat of genetic editing, past