Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Antibodies critical for fighting West Nile Virus infection

30.01.2003


Researchers at Washington University School of Medicine in St. Louis have found that immune cells called B cells and the antibodies they produce play a critical early role in defending the body against West Nile Virus. The results are published in the February issue of the Journal of Virology.



Mice that lacked B cells and antibodies were completely unable to combat the virus. They developed serious brain and spinal-cord infection and ultimately died.

"These findings may help explain why the elderly and others with weakened immunity are most likely to develop serious disease when infected by the virus," says study leader Michael S. Diamond, M.D., Ph.D., assistant professor of medicine, of molecular microbiology and of pathology and immunology.


West Nile Virus first emerged in the eastern United States in 1999 and has spread steadily westward, reaching the West Coast last year. It is carried by mosquitoes and causes encephalitis, a brain inflammation. The virus affects mainly birds, especially crows and jays, but it also can cause disease in horses, humans and other mammals.

In humans, West Nile Virus causes serious illness in only a small proportion of infected people. Last year, doctors reported more than 3,500 cases of infection, with 5 to 10 percent of those resulting in serious illness or death.

Diamond and his colleagues infected a strain of immune-deficient mice that lacked two important components of the immune system -- T cells and B cells -- and compared the animals’ response to mice with normal immunity. T cells coordinate immune responses and kill infected cells; B cells produce antibodies that attack viruses before they infect cells.

The immune-deficient mice became sick and died even with low doses of the virus. However, they could resist infection if given a dose of B cells after being injected with the virus.

"We were surprised by how susceptible the mice were when antibodies were missing," says Diamond. "Just one viral particle -- an exceedingly low dose -- was enough to kill the mice."

To confirm the importance of B cells and antibodies in defending against West Nile Virus, the researchers then gave the virus to a group of immune-deficient mice that lacked only B cells and antibodies, again comparing their response to mice with normal immunity. At day two, both the B-cell deficient mice and normal mice had equal levels of the virus in the blood. The levels declined thereafter in the normal mice and were undetectable by day six. In the B-cell deficient mice, however, viral levels continued to increase, with 500-fold higher levels by day four.

From this, the investigators conclude that B cells and antibodies appear to be essential for controlling the infection.

"Our findings suggest – but this is just speculation – that humans who have weak antibody responses early during infection are more likely to develop serious disease," says Diamond. "Those are the people we’d want to target when a vaccine or treatment becomes available."

Diamond and his colleagues now are studying how antibodies control infection and what other parts of the immune system are involved.


Diamond MS, Shrestha B, Marri A, Mahan D, Engle M. B cells and antibody play critical roles in the immediate defense of disseminated infection by West Nile Encephalitis Virus. Journal of Virology, February. 2003.

Funding from the National Institute of Allergy and Infectious Diseases supported this research.

The full-time and volunteer faculty of Washington University School of Medicine are the physicians and surgeons of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Darrell Ward | EurekAlert!
Further information:
http://medinfo.wustl.edu/

More articles from Health and Medicine:

nachricht 'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers
16.02.2018 | National University of Science and Technology MISIS

nachricht New process allows tailor-made malaria research
16.02.2018 | Eberhard Karls Universität Tübingen

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

'Lipid asymmetry' plays key role in activating immune cells

20.02.2018 | Life Sciences

MRI technique differentiates benign breast lesions from malignancies

20.02.2018 | Medical Engineering

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>