Researchers trick bacteria to deliver a safer vaccine

March 13, 2013
Yale researchers trick bacteria to deliver a safer vaccine
This rendering is of the molecular machine that helps bacteria infect cells. Yale researchers have learned how to use it to trigger immune responses.

(Medical Xpress)—Vaccines that employ weakened but live pathogens to trigger immune responses have inherent safety issues but Yale researchers have developed a new trick to circumvent the problem—using bacteria's own cellular mistakes to deliver a safe vaccine.

The findings, published online March 12 in Nature Communications, suggest new ways to create novel vaccines that effectively combat disease but can be tolerated by children, the elderly, and the immune-compromised 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," said Jorge Galan, senior author of the paper and the Lucille P. Markey Professor of Microbial Pathogenesis and chair of the Section of at Yale.

Galan's team has assembled the molecular machine used by Salmonella to cause food poisoning or . Scientists have been successful in modifying this protein injection machine to trigger a protective immune response against a variety of infectious diseases. However, it has been necessary to use modified or -attenuated bacteria that carry this machine.

The new trick exploits a mutation that causes bacteria to create "mini-cells" when they improperly divide. Mini-cells contain no DNA and, therefore, are not pathogenic and extremely safe. Galan's team was able to assemble the protein-injection machines within these , which when administered to mice, deliver antigens that trigger an immune response without causing an infection.

The system could be used to combat cancer as well as a wide variety of , Galan said.

Explore further: Researchers develop a vaccine prototype stronger than traditional vaccines

Related Stories

Recommended for you

Researchers grow retinal nerve cells in the lab

November 30, 2015

Johns Hopkins researchers have developed a method to efficiently turn human stem cells into retinal ganglion cells, the type of nerve cells located within the retina that transmit visual signals from the eye to the brain. ...

Shining light on microbial growth and death inside our guts

November 30, 2015

For the first time, scientists can accurately measure population growth rates of the microbes that live inside mammalian gastrointestinal tracts, according to a new method reported in Nature Communications by a team at the ...

Functional human liver cells grown in the lab

November 26, 2015

In new research appearing in the prestigious journal Nature Biotechnology, an international research team led by The Hebrew University of Jerusalem describes a new technique for growing human hepatocytes in the laboratory. ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.