|
|
|
Epstein-Barr virus and lupus
What problem was studied?
Epstein-Barr virus is one of the most common viruses that infect humans,
generally resulting in a very mild and brief illness in children. When EBV
affects adolescents or young adults, it can result in infectious mononucleosis,
a condition that results in fever, sore throat, swollen lymph glands and severe
fatigue. Although symptoms usually stop within a few months, EBV remains dormant
or latent in the body for the rest of the infected person's life and can become
reactivated. EBV infection is more common in people with systemic lupus
erythematosus (SLE or lupus) but it is not clear whether this is a cause or
effect of a faulty immune system in these individuals. In addition, people with
lupus often take drugs that suppress the immune system, making them more
susceptible to infections and cancer. To help prevent these complications,
research is needed to better understand how the immune system in people with
lupus defends against foreign invaders.
Arthritis
Foundation-funded researchers involved in the study: Insoo Kang, MD, supported
by an Arthritis Investigator Award; Timothy Quan, MD, supported by an
AF/American College of Rheumatology Physician Scientist Development Award; and
Joseph E. Craft, MD, supported by a Biomedical Science Grant and a Southern New
England Chapter grant, Yale University, New Haven, CT
What was done in the study?
The research team collected blood samples from people with lupus and from
healthy individuals to look at signs of EBV infection (called "viral
loads"). They also examined how the immune system in both groups handled
EBV infection by studying subsets of immune cells, called "T cells,"
which normally play a key role in defending the body against viral infections.
What were the study results?
The researchers found that the patients with lupus had a 40-fold increase in
signs of EBV infection compared to the healthy subjects. The people with lupus
had a higher frequency of one type of T cell (CD4) but a lower frequency of
another type of T cell (CD8). The team concluded that people with lupus have a
defect in their ability to control latent EBV infection that probably results
from altered T cell responses to the virus.
What's the relevance to people with lupus?
This study is important because it begins to provide insights about how people
with an abnormal immune system, such as in lupus, respond to infection. Adds Dr.
Kang, "This is clinically important research since patients with autoimmune
diseases like lupus are frequently treated with strong immunosuppressive drugs
that may suppress immune responses against infection. In this study, we have
shown that patients with SLE have defective control of latent EBV infection.
However, the clinical significance of such a defect is still elusive and should
be determined with future studies."
Source: Journal of Immunology, January
2004 http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14707107&dopt=Abstract
  
Research Update is compiled by
Michele Boutaugh, BSN, MPH, Medical and Scientific Affairs Department,
National Office.
|
