The MAPS (Multiple Antigen Presentation System) technology, developed by the lab of Dr. Richard Malley of Children’s Hospital Boston, partners a polysaccharide (PS) scaffold with a coupling system whereby a number of proteins can be collectively bound to the PS. In vivo, this system can prime strong antibodies against PS and also specific B cell and T cell responses to protein antigens.
Current conjugate vaccines use chemical-cross linking reaction to connect PS to the carrier protein, which Malley’s lab says is an inefficient and expensive process.
“If one compares MAPS to traditional conjugate vaccines (in which polysaccharide and protons are chemically coupled) MAPS is certainly less expensive to manufacture,” Dr. Malley told BioPharma-Reporter.com. “There are far fewer reagents and steps required and the efficiency of manufacture is substantially higher, resulting in much reduced costs.”
Vaccines in Development
Maley said his lab is “actively developing a multivalent pneumococcal vaccine in which the pneumococcal polysaccharides of interest (13 of them) are affinity bound to conserved pneumococcal proteins to provide protection not only against the 13 serotypes represented but also other serotypes (by virtue of generating responses to the pneumococcal proteins).
“We are also developing a combined TB (tuberculosis) vaccine by incorporating TB proteins with polysaccharides from other pathogens (such as pneumococcus, haemophilus influenzae or salmonella typhi),” he said.
Work on a staphylococcus aureus vaccine is also beginning as well, and in the near future the lab will work to make vaccines against whooping cough and pathogens that afflict hospitalized patients, he said.
Dr. Malley stressed that this new technology still needs “to be carefully assessed for safety and reactogenicity in adults and children” since it triggers robust T cell responses in animals.
“We believe that in many cases (e.g. Pneumococcus, Tuberculosis, Pertussis) this could be very advantageous, but of course it could be that such T cell responses could lead to an increased risk of side effects,” Dr. Malley told us.
However, because the number of antigens included is lower than with WCVs (whole cell vaccines), this risk is likely reduced, he noted.