Featured Research

from universities, journals, and other organizations

Link Between Chlamydia Infections And Heart Disease Reported In Science

Date:
March 1, 1999
Source:
American Association For The Advancement Of Science
Summary:
A new study shows how Chlamydia infections may be linked to heart disease. The evidence, presented in the 26 February issue of Science, suggests that Chlamydia employ a sneaky tactic known as "molecular mimicry" that triggers an autoimmune response in the host and ultimately leads to inflammation of the heart.

Washington D.C. - A new study shows how Chlamydia infections may be linked to heart disease. The evidence, presented in the 26 February issue of Science, suggests that Chlamydia employ a sneaky tactic known as "molecular mimicry" that triggers an autoimmune response in the host and ultimately leads to inflammation of the heart.

In the past, several epidemiological studies, which track the occurrence of disease in large populations, have shown an intriguing correlation between Chlamydia infections and heart disease. Until now, however, the mechanism that might link the two has remained a mystery. It is clear that both disorders are significant public health problems. Chlamydia is a primary cause of sexually transmitted diseases and female infertility, and can also cause eye infections and pneumonia in children. Meanwhile, heart disease is the major cause of death in Western societies.

Kurt Bachmaier, of the Ontario Cancer Institute and University of Toronto, and his colleagues in Canada, Austria, and the U.S., now show that the link between Chlamydia infections and heart disease appears to involve what is known as an autoimmune disorder. Like the proverbial wolf in sheep's clothing, some pathogens carry proteins on their surfaces that are almost identical to proteins on the host's cells. These proteins enable the pathogens to evade the host's immune system by "passing" as part of the host's own body. Sometimes, however, the immune system is not fooled by this subterfuge and launches an attack. An autoimmune disorder arises when the attack damages the host's cells in the process.

Bachmaier and his colleagues found that a specific piece of a protein on Chlamydia's surface is a dead ringer for another piece of the protein in the heart muscle of mice known as "myosin." Their findings suggest that a Chlamydia infection, in the lungs or reproductive organs, for example, triggers a local immune response that can be followed by a system-wide activation of the immune system. An autoimmune disorder in the heart occurs when the host's immune cells also direct their attack towards the heart muscle myosin.

Previous studies have shown that injecting mice with this type of myosin resulted in inflammatory heart disease. Bachmaier's group identified the specific section, or peptide sequence, of the myosin molecule that induced the disease. The researchers then screened a public databank for viral and bacterial sequences that matched the myosin peptide sequence. They found matches in peptides from proteins on the outer membranes of three different Chlamydia strains. When the group injected mice with the Chlamydia peptides, these peptides activated the same immune cells as the heart muscle myosin and also induced inflammatory heart disease.

Chlamydia infections are so common that most people can expect to experience at least one during their lifetimes. In the researchers' mouse model, whether or not an infection led to heart disease depended on genetic differences among the various strains of inbred mice. The researchers speculate that genetic and environmental risk factors may also predispose certain humans to Chlamydia-mediated heart disease.


Story Source:

The above story is based on materials provided by American Association For The Advancement Of Science. Note: Materials may be edited for content and length.


Cite This Page:

American Association For The Advancement Of Science. "Link Between Chlamydia Infections And Heart Disease Reported In Science." ScienceDaily. ScienceDaily, 1 March 1999. <www.sciencedaily.com/releases/1999/03/990301073218.htm>.
American Association For The Advancement Of Science. (1999, March 1). Link Between Chlamydia Infections And Heart Disease Reported In Science. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/1999/03/990301073218.htm
American Association For The Advancement Of Science. "Link Between Chlamydia Infections And Heart Disease Reported In Science." ScienceDaily. www.sciencedaily.com/releases/1999/03/990301073218.htm (accessed October 22, 2014).

Share This



More Health & Medicine News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
US to Track Everyone Coming from Ebola Nations

US to Track Everyone Coming from Ebola Nations

AP (Oct. 22, 2014) Stepping up their vigilance against Ebola, federal authorities said Wednesday that everyone traveling into the US from Ebola-stricken nations will be monitored for symptoms for 21 days. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Doctors Help Paralysed Man Walk Again, Patient in Disbelief

Doctors Help Paralysed Man Walk Again, Patient in Disbelief

AFP (Oct. 22, 2014) Polish doctors describe how they helped a paralysed man walk again, with the patient in disbelief at the return of sensation to his legs. Duration: 1:04 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins