A team of scientists has developed a new blood test that simultaneously detects the presence of circulating antibodies to more than 1000 strains of 206 known human viruses. In essence, the test profiles an individual’s lifetime history of viral infections.
Published in Science, the method is technically complex, but cheap to administer — requiring only a tiny drop of blood. Using a combination of microarray technology, phage display and DNA sequencing, known viral peptide epitopes (the parts of viruses targeted by human antibodies) are used to capture existing antiviral antibodies. Such antibodies are only present if a person was previously infected. Testing previously could only be done for only one viral strain at a time, but now can be accomplished in one fell swoop.
A group of 569 people of varying ages and geographical location was profiled. Subjects were found to have been exposed to about 10 virus species on average, though the number varied from patient to patient. At one extreme, two individuals were found to have been infected by at least 84 species. Interestingly, the study found that some epitopes were remarkably common across the population, suggesting that for some viruses, there were common “public epitopes” elicited over and over again.
The new methodology opens up exciting possibilities for studying the effects of viral infections on causation of human diseases such as cancer, multiple sclerosis, and type I diabetes.