Lyme disease is the most common vector-borne infectious disease in the United States, in part because there is currently no human vaccine against it. In a recent research report titled “Development of an mRNA-lipid nanoparticle vaccine against Lyme disease,” published in the international journal Molecular Therapy, scientists from the University of Pennsylvania and other institutions have developed an experimental mRNA vaccine that may offer protection against infections caused by Borrelia burgdorferi, the pathogen responsible for Lyme disease, in preclinical animal models. The study results suggest that this new type of vaccine may prevent the occurrence of Lyme disease and could serve as a powerful tool to reduce Lyme disease cases.

The pathogen responsible for Lyme disease is transmitted to humans through infected ticks, leading to symptoms such as fever, headache, fatigue, and a characteristic skin rash. If not promptly treated, the infection can spread to the joints, heart, and nervous system. While most Lyme disease patients can recover with a few weeks of antibiotic treatment, some patients develop post-treatment Lyme disease syndrome (PTLDS) after therapy. PTLDS can lead to long-term symptoms such as severe joint pain and cognitive issues. Despite vaccines being available for canine Lyme disease, there is no approved vaccine for preventing Lyme disease in humans.

Dr. Norbert Pardi, one of the researchers, explained that bacteria are more complex organisms than viruses, making the development of effective vaccines against bacterial infections a challenge for scientists. In this article, we were presented with a potential target for an mRNA vaccine that showed great promise in preventing infections with Borrelia burgdorferi in animal models. This vaccine uses the same messenger ribonucleic acid (mRNA) technology as the Pfizer and Moderna COVID-19 vaccines, representing a pioneering technology for the researchers involved. Through collaborative research, the scientists identified a specific protein in Borrelia burgdorferi called Outer Surface Protein A (OspA), which has the potential to induce a strong immune response. OspA is a conserved protein in various Borrelia burgdorferi strains, making it an ideal target to help prevent the progression of initial infections to Lyme disease.

Animal tests showed that a single injection of the mRNA vaccine targeting OspA could make the body produce strong antigen-specific antibodies and T-cells, which would protect against getting infected with Borrelia burgdorferi. Furthermore, the vaccine also elicited a robust memory B-cell response that could be activated for an extended period after vaccination, helping to prevent infections caused by Borrelia burgdorferi.

Researchers note that Lyme disease cases have been rapidly increasing in the United States in recent years. This emphasizes the need for researchers to develop vaccines that protect humans from infection, and mRNA technology holds the promise to achieve this goal, preventing both Lyme disease and the subsequent onset of PTLDS symptoms.