A “smart” vaccine designed to destroy bacteria before the beginning of the colonization process is under development by researchers at the University of Buffalo in collaboration with Abcombi Biosciences, a preclinical-stage biotechnology company. This novel approach would help patients with infectious diseases such as pneumonia.
The research study, “Directed vaccination against pneumococcal disease,” was recently published in PNAS.
Pneumonia, characterized by inflamed air sacs in the lungs, is primarily caused by bacterial infection due to Streptococcus pneumoniae, known as pneumococcus. With approximately 1.3 million deaths worldwide as of 2011, pneumonia is considered a leading cause of death, especially in children under the age of 5. According to the World Health Organization, pneumonia accounts for 15 percent of all deaths of children younger than 5.
The prevention and treatment of bacterial infections like pneumonia is currently achieved through penicillin and other common antibiotics. But bacteria are rapidly and continuously developing resistance to antibiotics, which makes the development of therapies more challenging. Also, the approach used by currently available vaccines is based on the identification of the bacteria by their sugary coatings, an approach that makes them less effective (56 to 88 percent effective).
The novel proposed approach is based on the identification of strains using particular proteins connected to the bacteria’s surface. This increases the selectivity and effectiveness to 100 percent, according to lab tests, in boosting appropriate immune response.
“With conventional vaccines, the approach has been: ‘What bacteria do we want to target and how,'” Abcombi founder and CEO Dr. Charles H. Jones said in a press release. “Our strategy is to shift the paradigm to, which diseases do we want to prevent.”
While current vaccines prevent bacterial colonization through attacks and destruction of bacteria by the immune system, the smart vaccine works differently. It leaves bacteria to coexist in the system and orders the immune system to attack only if the bacteria loses the proteins from its coatings, which is indicative of the start of infectious colonization.
“That’s the signal that this bacteria is becoming a troublemaker, that it’s threatening the body and that it’s necessary to fight back,” said Dr. Blaine A. Pfeifer, associate professor of chemical and biological engineering at the University at Buffalo School of Engineering and Applied Sciences.
Preliminary studies based on computer simulations suggested that the “smart” vaccine would be efficient against all strains, important due to cost and time factors. However, more tests are required to strengthen the findings.
“It’s like the arcade game Whac-A-Mole. Think of the mallet as a traditional vaccine. It can’t stop all the moles, or in our case, all the strains of bacteria at once,” Jones said. “But our vaccine does just that. It’s like a mallet with 90 heads that strikes all the moles simultaneously.”
As the vaccine’s effectiveness on animals testing was shown to be positive, Abcombi is currently planning to start human trials.
