How do antibodies circulate throughout the body?

Antibodies circulate throughout the body predominantly through the bloodstream. Once produced by B cells, antibodies are released into the circulation where they can travel rapidly to various tissues and organs. This circulation is crucial for their role in the immune response, as it allows antibodies to efficiently encounter and bind to specific antigens, leading to their neutralization or marking them for destruction by other immune cells.

While antibodies can also enter the lymphatic system and may be found in tissues through various mechanisms, their main mode of transport remains the bloodstream. This widespread distribution allows the immune system to respond quickly to infections and other immune challenges. The ability to travel throughout the circulatory system highlights the importance of the vascular system in providing a means for rapid and systemic immune responses.