A human protein that helps varicella-zoster virus (the cause of chickenpox and shingles) to spread from cell to cell within the body, has recently been identified by a team of scientists from the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health (NIH).

A surface protein of varicella-zoster virus called insulin-degrading enzyme, attaches to a cellular protein, using it as a receptor to enter and infect cells.

NIAID virologist Jeffrey I. Cohen, M.D., and NIAID research fellow Qingxue Li, M.D., Ph.D., also describe how interfering with this interaction inhibits the spread of virus among cells in the test tube in the October 20, 2006 issue of the journal Cell.

The discovery of this receptor, according to the research team is important in understanding varicella-zoster virus and also an important first step towards designing new therapies for shingles.

Shingles occurs only in people who have already had chickenpox. Once chickenpox has run its course, some virus remains dormant in nerve cells at the base of the brain and alongside the spinal cord.

With advancing age and diminished immunity, the virus can reactivate years later and travel down the nerve cells to the skin. There it multiplies, causing the blistering rash of shingles and damaging sensory nerve endings.

The rash usually heals within a few weeks, but the nerve damage sometimes causes one of the worst complications of shingles--a severe type of pain called postherpetic neuralgia, which can last for months or even years.

Even if the USFDA has already licensed a a shingles vaccine for people 60 and older, some people who are the most vulnerable to shingles--people with AIDS and others who are severely immunocompromised--cannot receive the vaccine because it is made from a live virus.

Find more details from NIH News.

[Photo Credit: Wichita State University]