What function do dendritic cells serve in the immune system?

Dendritic cells play a crucial role in the immune system primarily by presenting antigens to T cells. They are specialized antigen-presenting cells that capture and process foreign substances, effectively acting as a bridge between the innate and adaptive immune responses. When dendritic cells encounter a pathogen, they engulf it and process the proteins from the pathogen into smaller peptides. These peptide fragments are then loaded onto major histocompatibility complex (MHC) molecules and presented on the surface of the dendritic cells.

Once the dendritic cells present these processed antigens, they migrate to the lymph nodes where they interact with T cells. This interaction is critical, as it helps activate T cells, thus initiating a specific immune response tailored to eliminate the particular pathogen. This antigen presentation process is essential for the adaptive immunity to function effectively.