Featured Research

from universities, journals, and other organizations

Sandfly saliva provides important clues for new Leishmaniasis treatments

Date:
August 31, 2011
Source:
Federation of American Societies for Experimental Biology
Summary:
For millions threatened with Leishmania infection, new research points to breakthroughs preventing these parasites from taking hold in the body or reducing the severity of infections. A new report shows specific molecules found in saliva of the sandfly allow for Leishmania to evade neutrophils and live within human hosts. Along with providing new targets for drug development, this discovery may help doctors accurately gauge the severity of infections.

For millions of people who live under the constant threat of Leishmania infection, a new discovery by Brazilian scientists may lead to new breakthroughs, preventing these parasites from taking hold in the body or reducing the severity of infections once they occur. In a new report appearing in the Journal of Leukocyte Biology, scientists show that specific molecules found in the saliva of the sandfly -- a small flying insect that is the vector for the parasite -- make it possible for Leishmania to evade neutrophils and live within human hosts. In addition to providing a new target for drug development, this discovery may lead to new tools that help doctors more accurately gauge the severity of infections.

"Neutrophils are considered the host's first line of defense against infections and have been implicated in the immunopathogenesis of leishmaniasis, the disease caused by Leishmania," said Valeria Borges, a Brazilian researcher involved in the work. "The identification of specific key factors from neutrophils linked to human visceral leishmaniasis immunopathogenesis can lead to the description of potential biomarkers for disease severity."

To make their discovery, scientists studied how the sandfly (Lutzomyia longipalpis), an important vector of visceral leishmaniasis, affected the neutrophils of hosts. They found that the salivary components of the sandfly induced neutrophil death pathways including FasL-mediated and caspase-dependent apoptosis, and this event was associated with Leishmania survival inside these dying cells. According to the U.S. Centers for Disease Control and Prevention, cutaneous leishmaniasis and visceral leishmaniasis are caused by more than 20 different leishmanial species. Cutaneous leishmaniasis is the most common form of the disease and causes skin ulcers. Visceral leishmaniasis causes a severe systemic disease that is usually fatal without treatment. Mucocutaneous leishmaniasis is a rare but severe form affecting the nasal and oral mucosa. The disease is transmitted by the bite of sand flies, and many leishmanial species infect animals as well as humans. The distribution of the disease is world-wide, with 90 percent of cutaneous leishmaniasis cases occurring in Afghanistan, Algeria, Iran, Saudi Arabia, Syria, Brazil, Colombia, Peru, and Bolivia and 90 percent of visceral leishmaniasis cases occurring in India, Bangladesh, Nepal, Sudan, Ethiopia, and Brazil.

"We are fortunate in the United States that when most of us think of bug bites we do not have to imagine picking up a parasite that can cause open wounds or major systemic problems in our bodies," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. "However, for the majority of the developing world this is a substantial problem and finding ways to prevent or cure this insect transmitted diseases urgent global health priority. This research report looks beyond the parasite to see what other factors facilitate its colonization. Their discovery that the sand fly's saliva plays a critical role in the process for Leishmania should reveal new opportunities for therapeutics against this parasite."


Story Source:

The above story is based on materials provided by Federation of American Societies for Experimental Biology. Note: Materials may be edited for content and length.


Journal Reference:

  1. D. B. Prates, T. Araujo-Santos, N. F. Luz, B. B. Andrade, J. Franca-Costa, L. Afonso, J. Clarencio, J. C. Miranda, P. T. Bozza, G. A. DosReis, C. Brodskyn, M. Barral-Netto, V. de Matos Borges, A. Barral. Lutzomyia longipalpis saliva drives apoptosis and enhances parasite burden in neutrophils. Journal of Leukocyte Biology, 2011; 90 (3): 575 DOI: 10.1189/jlb.0211105

Cite This Page:

Federation of American Societies for Experimental Biology. "Sandfly saliva provides important clues for new Leishmaniasis treatments." ScienceDaily. ScienceDaily, 31 August 2011. <www.sciencedaily.com/releases/2011/08/110831115935.htm>.
Federation of American Societies for Experimental Biology. (2011, August 31). Sandfly saliva provides important clues for new Leishmaniasis treatments. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2011/08/110831115935.htm
Federation of American Societies for Experimental Biology. "Sandfly saliva provides important clues for new Leishmaniasis treatments." ScienceDaily. www.sciencedaily.com/releases/2011/08/110831115935.htm (accessed September 18, 2014).

Share This



More Plants & Animals News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Chimp Violence Study Renews Debate On Why They Kill

Chimp Violence Study Renews Debate On Why They Kill

Newsy (Sep. 17, 2014) The study weighs in on a debate over whether chimps are naturally violent or become that way due to human interference in the environment. Video provided by Newsy
Powered by NewsLook.com
Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
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:
from the past week

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