DNA Arrays Give Clues For Better Vaccines.(Brief Article)

2002 FEB 20 - (NewsRx.com & NewsRx.net) -- New clues about the way immune cells communicate with invading pathogens may lead to better vaccines, according to a report in the February 5, 2002, issue of Proceedings of the National Academy of Sciences USA.

"We are in the midst of a revolution in the way researchers study infectious disease," said Richard Young of the Whitehead Institute of Biomedical Research. "Instead of depending on culture dishes as the only way to observe the behavior of pathogens, scientists are able to 'eavesdrop' on the cross-talk between invading microbes and the immune cells of our body."

Young and colleagues have done this using DNA microarrays to explore the responses of human macrophages to a variety of bacteria, and their research ultimately may lead to safer, more potent vaccines.

Macrophages, immune cells that are part of the first line of defense, recognize and engulf microbes in a vigilant effort to keep the body healthy. The researchers found that macrophages respond to a broad range of bacteria by sending off an alarm to the rest of the immune system and transforming into a cell primed to mount an immune response.

Further study revealed that the macrophage didn't have to "see" the whole bacteria to send off its alarm signal, but the presence of specific bacterial components, such as proteins and sugars, induced activation.

"These findings will help researchers design therapeutics that will stimulate the immune system in a targeted manner, perhaps with fewer side effects," said Young, lead author on the study.

"The interplay between a person's immune mechanisms and a microbe's attempts to circumvent these defenses represents a complex relationship. DNA arrays help researchers dissect this struggle by measuring the activity of many genes in the immune cells as they respond to pathogens. As a result, researchers gain invaluable information about the strengths and vulnerabilities of the microbes and our own immune system during an infection," explained Gerard Nau, a first coauthor on the study and a researcher in the Young lab. Ann Schlesinger, postdoctoral fellow in the Young lab, and Joan Richmond, former Young lab member, were also first authors on the paper.