Search Here

Scientists can make vaccines more effective by using weakened but live pathogens to trigger immune responses.  While the technique has safety issues, scientists at Yale University have developed a way to make the vaccine safer by using the bacteria's own cellular mistake to deliver a safe vaccine.

The research, published March 12 in Nature Communications, suggest that the new technique can be used to create novel vaccines that effectively combat disease but can also be tolerated by children, older people and immune-compromised people who might be harmed by live vaccines.

"We have managed to assemble a functional protein-injection machine within bacterial mini-cells, and the amazing thing is that it works," senior author Jorge Galan, a Lucille P. Markey Professor of Microbial Pathogenesis and chair of the Section of Microbial Pathogenesis at Yale, said in a statement.

Galan and his team made the new vaccine using the bacteria Salmonella to cause food poisoning or typhoid fever. In the past researcher have been able to successfully modify this protein injection machine to trigger a protective immune response against a range of infectious diseases.  However, in order for the vaccine to be sage in people, scientists needed to use modified or virulence- attenuated bacteria that carry this machine.

Researcher said that new trick uses a glitch mutation that causes bacteria to create "mini-cells" when they improperly divide. Scientists explain that mini cells to not have DNA, and therefore are not pathogenic and extremely safe.  Researchers in the latest study were able to harness this mutational glitch and create the protein-injection machines within these "mini-cells".  Galan said that mice given the vaccine had an immune response and no infection, adding that the new technique could be used to treat a variety of infectious diseases and even cancer.