Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Building better therapeutic vaccines for chronic infections

04.07.2005


Study finds that poor T cell responsiveness limits current approaches



In recent years, researchers have become increasingly interested in developing therapeutic vaccines. Most Americans are familiar with prophylactic, or preventive vaccines, which protect an individual from infections; examples include the common pediatric vaccines as well as the flu shot. But therapeutic vaccines are designed instead to be administered to patients who have already acquired chronic infections, such as HIV or hepatitis. These therapeutic vaccines aim to enhance the immune system’s ability to combat an infectious agent, such as a virus. Researchers are also developing therapeutic vaccines to treat a variety of cancers.

But many experimental therapeutic vaccines have thus far fallen short of expectations. Now, scientists at The Wistar Institute and Emory University offer details about what may prevent the immune system from responding effectively to a therapeutic vaccine during a state of chronic infection. Their findings suggest how scientists might alter therapeutic vaccination approaches to make the immune system respond better. Their work is published today in the Journal of Virology.


"In this study, we wanted to look at why therapeutic vaccines are generally less effective than prophylactic vaccines," says E. John Wherry, Ph.D., assistant professor in Wistar’s Immunology Program and lead author of the study. Wherry conducted the research as a postdoctoral fellow in the Emory University laboratory of Rafi Ahmed, Ph.D., before joining Wistar earlier this year. "What we found was that the T cells in the chronically infected mice responded poorly to the vaccine."

Specifically, Wherry says, the T cells failed to proliferate, or expand in number. This failure to proliferate seemed to correlate with a high viral load, which suggests several directions researchers might pursue in improving response to therapeutic vaccines.

"The ongoing stimulus to the immune system that occurs in chronic infection seems to prevent the immune cells from responding optimally to a therapeutic vaccine," Wherry says. "If we could lower viral load before therapeutic vaccination, we might be able to improve efficacy."

The next step for the research, Wherry says, will be to combine therapeutic vaccines with other modalities that either lower viral load or enhance T cell function, particularly the proliferative capacity of T cells. Possible examples include anti-virals that could be given prior to therapeutic vaccination, or a cytokine that might boost the proliferation or survival of responding cells.

Wherry’s group at Wistar is continuing to work on understanding at a fundamental level why the T cell proliferation is poor when a therapeutic vaccine is administered during a state of chronic infection. He is also planning to compare the immune response using different therapeutic vaccine platforms. While Wherry’s primary interest is in chronic infection, he notes that research in this area should inform the design of better therapeutic cancer vaccines as well because many of the deficiencies in immune response are similar whether the antigen confronting the immune system is a virus or a tumor.

In addition to Wherry and senior author Ahmed, the other co-author of the paper is Joseph N. Blattman, Ph.D., of Fred Hutchinson Cancer Research Center. Funding for the work was provided by the National Institutes of Health and the Cancer Research Institute.

Franklin Hoke | EurekAlert!
Further information:
http://www.wistar.org

More articles from Health and Medicine:

nachricht Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University

nachricht The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>