Blood Test Could Speed Bioterror Care
FRIDAY, Feb. 17 (HealthDay News) -- A test focused on genetic changes in white blood cells could be a quick means of confirming whether someone has been exposed to a bioterrorism agent, scientists say.
"We see very specific changes in gene expression that are quite unique to each pathogen as little as two hours after exposure," researcher Rasha Hammamieh, of the Walter Reed Army Institute of Research, in Silver Springs, Md., said in a prepared statement.
Hammamieh noted that "effective prophylaxis and treatment for infections caused by biological threat agents rely upon early diagnosis and rapid initiation of therapy." However, available diagnostic methods take a relatively long time because they require that the germ in question "proliferate to detectable and dangerous levels, thereby delaying diagnosis and treatment," she said.
But she and her colleagues found that within minutes of exposure to a bioterror agent, white blood cells (leukocytes) course through the body and a record any abnormal encounters in a particular gene expression.
The researchers first drew blood from healthy volunteers and then screened blood leukocytes to establish a baseline for gene expression in samples not exposed to pathogens. They then exposed the samples to a number of different pathogens (including bioterrorism agents) and bacterial toxins. Those results were later confirmed in tests with animals.
"Use of mathematical modeling tools has identified a list of over 300 genes that can discriminate among eight pathogenic agents with 99 percent accuracy," Hammamieh said.
She and her colleagues are also trying to identify gene-expression patterns that could help determine the severity of exposure to pathogenic agents.
The findings were presented Thursday at a meeting of the American Society of Microbiology's Biodefense Research Meeting, in Washington, D.C.
This research might eventually lead to the development of hand-held devices that could be used at the site of a suspected bioterrorism attack to quickly identify people who may have been exposed, Hammamieh said.
"The technology is not there yet, but within 10 years, this test could also be done in doctors' offices for a variety of common illnesses, including some types of cancer," she added.
The U.S. Centers for Disease Control and Prevention has more about bioterrorism agents and diseases.