Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists discover how deadly fungus protects itself

05.02.2009
Finding could lead to new therapies or vaccine for Cryptococcus neoformans

Researchers at Albert Einstein College of Medicine of Yeshiva University have discovered how a deadly microbe evades the human immune system and causes disease.

The study, published in the journal Proceedings of the National Academy of Sciences (PNAS), may help scientists develop new therapies or vaccines against infections caused by Cryptococcus neoformans. These fungal infections occur most commonly in those with compromised immune systems ©¤ especially AIDS patients and transplant patients who must take lifelong immunosuppressive therapy.

The fungus causes an estimated one million deaths each year worldwide, including some 600,000 in sub-Saharan Africa. The lead author of the study was Susana Frases-Carvajal, Ph.D., a postdoctoral fellow in microbiology & immunology at Einstein.

C. neoformans typically enters the body through the lungs and can spread throughout the body, including the brain. The resulting infection, called cryptococcosis, can cause chest pain, dry cough, abdominal swelling, headache, blurred vision, or confusion. The infection can be fatal, especially if not treated with antifungal medications.

"It's a horrendous disease, and even with therapy, you often can't get rid of it," says the paper's senior author, Arturo Casadevall, M.D., Ph.D., professor and chair of microbiology & immunology.

Scientists have known that the capsule surrounding C. neoformans is essential to its ability to cause disease. When the fungus enters a host, the capsule begins to enlarge. "As the capsule grows larger, it reaches a point where immune system scavenger cells, known as macrophages, can't swallow it," says Dr. Casadevall. "But we didn't understand the mechanism responsible for capsule growth."

The protective capsule of C. neoformans is composed of polysaccharides, which are long chains of sugar molecules, or saccharides. Using a technique called dynamic light scattering, Dr. Frases and her colleagues found that the capsule grows by linking more and more saccharides together at the outer edge of the capsule, forming giant molecules pointing in an outward, or axial, direction.

The findings point to potential new targets for drug intervention and reveal a new area of investigation into basic polysaccharide biology. Polysaccharides are poorly understood, partly because of the difficulty of working with them. "Also, scientists have tended to view polysaccharides as boring molecules that simply grow to a specified length," says Dr. Casadevall.

"But this study raises huge questions about polysaccharides," he adds. "For example, how does the organism assemble these molecules, and how does it know how to make molecules that are roughly the same length? We don't know. There appears to be a whole dimension of cellular machinery that we never knew existed."

The other co-authors of the paper, all of Universidade Federal do Rio de Janeiro, Brazil, are: Bruno Pontes, Leonardo Nimrichter, Marcio L. Rodrigues, and Nathan B. Viana.

The study, "Capsule of Cryptococcus neoformans grows by enlargement of polysaccharide molecules," appears in the January 27 issue of PNAS. http://www.pnas.org/content/106/4/1228.abstract

About Albert Einstein College of Medicine of Yeshiva University

Albert Einstein College of Medicine of Yeshiva University is one of the nation's premier centers for research, medical education and clinical investigation. It is the home to some 2,000 faculty members, 750 M.D. students, 350 Ph.D. students (including 125 in combined M.D./Ph.D. programs) and 380 postdoctoral investigators. Last year, Einstein received more than $130 million in support from the NIH. This includes the funding of major research centers at Einstein in diabetes, cancer, liver disease, and AIDS. Other areas where the College of Medicine is concentrating its efforts include developmental brain research, neuroscience, cardiac disease, and initiatives to reduce and eliminate ethnic and racial health disparities. Through its extensive affiliation network involving five hospital centers in the Bronx, Manhattan and Long Island ¨C which includes Montefiore Medical Center, Einstein's officially designated University Hospital ¨C the College runs one of the largest post-graduate medical training program in the United States, offering approximately 150 residency programs to more than 2,500 physicians in training.

Michael Heller | EurekAlert!
Further information:
http://www.aecom.yu.edu

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>