HIV virus (red) slips between loosely connected skin cells to reach its immune cell targets such as the Langerhans cells (orange), macrophages (purple), dendritic cells (green) and CD4 positive T cells (blue)
Instead of infiltrating breaks in the skin, HIV appears to attack normal, healthy genital tissue in women, U.S. researchers said on Tuesday in a study that offers new insight into how the AIDS virus spreads.
They said researchers had assumed the human immunodeficiency virus, or HIV, sought out breaks in the skin, such as a herpes sore, in order to gain access to immune system cells deeper in the tissue.
Some had even thought the normal lining of the vaginal tract offered a barrier to invasion by the virus during sexual intercourse.
"Normal skin is vulnerable," Thomas Hope of Northwestern University's Feinberg School of Medicine said in a telephone interview.
"It was previously thought there had to be a break in it somehow," said Hope, who is presenting his findings at a meeting of the American Society for Cell Biology in San Francisco.
He said until now, scientists had little understanding of the details of how HIV is transmitted sexually in women.a
