Yale School of MedicineLyme disease is a bacterial illness that is spread by tick bites which can affect the heart, skin, joints and the nervous system. A new research from Yale University claims that a protein present in the saliva of ticks may aid in shielding mice from contracting Lyme disease.

This could prompt growth of a new vaccine against infection from Lyme disease. Conventionally, vaccines have directly aimed at particular pathogens. This is claimed to be the first time that antibodies against a protein in the saliva of a pathogen’s transmitting agent has supposedly been exposed to bestow immunity when administered protectively as a vaccine.

The Lyme bacterium known as Borrelia burgdorferi is spread by ticks. When it moves through the tick, it is supposedly covered with a tick salivary protein called Salp15. The Yale team apparently inserted Salp15 into healthy mice and discovered that it could considerably defend them from developing Lyme disease. When merged with outer surface proteins of B. burgdorferi, the protection was said to be even greater.

Lead author Erol Fikrig, M.D. of Yale School of Medicine and Howard Hughes Medical Institute, commented, “The interaction between the Lyme disease agent and ticks is very complex, and the bacteria uses a tick salivary protein to facilitate infection of the mammalian host. By interfering with this important interaction, we can influence infection by the Lyme disease agent.”

Fikrig explained, “We believe that it is likely that many arthropod-borne infection agents of medical importance use vector proteins as they move to the mammalian host. If so, then this paradigm, described with the Lyme disease agent, is likely to be applicable to these illnesses. Currently, we are working to determine if this strategy is likely to be important for West Nile virus infection, dengue fever, and malaria, among other diseases.”

Many years ago, there was a Lyme vaccine on the market that apparently made use of just the external surface proteins of the bacteria. It was supposedly taken off the market in 2002, and to date apparently no other antigen has been examined in phase III clinical trials.

The authors are of the opinion that this new policy of aiming the saliva i.e. the ‘vector molecule’ that a microbe needs to contaminate a host could be appropriate not just to Lyme disease but to other insect-borne pathogens that may also cause human illness.

The findings are published in Cell Host and Microbe.