Borrelia burgdorferi Outer Surface Protein A (OspA)

Borrelia burgdorferi outer surface protein A (OspA) is a major lipoprotein found on the surface of the Lyme disease spirochete, B. burgdorferi. OspA is highly immunogenic and plays a critical role in the bacterium’s life cycle, particularly during its residence in tick vectors. It is essential for colonization and survival within ticks and serves as a target for protective antibodies. Vaccines based on OspA have shown efficacy in preventing Lyme disease by blocking transmission at the tick stage.

Other names

Outer Surface Protein AOsp A

Vaccines based on OspA elicit antibodies that block B. burgdorferi transmission from ticks to vertebrate hosts by binding to OspA within the tick gut, leading to spirochete death or preventing their migration to the salivary glands.