Scientists have developed a method for “tricking” the body into fighting the spread of some vaccine-resistant diseases such as HIV, malaria, and tuberculosis.
A team of researchers at the California Institute of Technology has developed a technique called vectored immunoprophylaxis, or VIP, that triggers an immune response to some types of infectious diseases.
Researchers have encoded genes from antibodies that have proven to fight infections into a harmless adeno-associated virus (AAV), which is then injected into muscle tissue to generate specified antibodies that enter the circulatory system and fight infection.
The Caltech group, led by Nobel laureate David Baltimore, reported in 2011 to Nature that they had used the technique to protect mice from HIV infection – even at exposures up to 100 times higher than what should have been necessary to cause the disease.
"All of the exposures in this work were significantly larger than a human being would be likely to encounter," said Alejandro Balazs, the lead author of that previous study.
Baltimore’s team is working with a manufacturer to produce material needed for clinical trials of that technique in humans.
They’ve also been working on developing the technique to fight influenza A – which causes about 20,000 deaths each year despite widely available vaccinations against the infection.
The influenza virus evolves quickly to avoid resistance, which makes yearly and reformulated vaccinations necessary.
But the researchers began identifying about five years ago some anti-influenza antibodies that can prevent infection for many strains of the rapidly changing virus
Baltimore’s group bound the genes from two of these antibodies last year into an AAV that protected mice against multiple flu strains – and the method worked even in older mice and those without a properly functioning immune system.
The scientist said VIP can protect mice “completely against flu” without the need for yearly vaccinations, and now the researchers are trying to determine how much of the antibody humans need to produce the same results.
Researchers at Johns Hopkins University have achieved similar results against malaria, and scientists at The Rockefeller University have adapted VIP for use against hepatitis C.
