antigen-presenting cell
Quick Summary
Antigen-presenting cells (APCs) are crucial components of the immune system that specialize in processing and displaying antigens. These cells, including dendritic cells, macrophages, and B cells, engulf foreign invaders like viruses, break them down, and present fragments (antigens) on their surface. This presentation occurs in conjunction with major histocompatibility complex (MHC) molecules.12
When APCs display these antigen fragments to T cells, particularly helper T cells, it triggers an immune response. This interaction activates T cells, enabling them to identify and combat specific pathogens. APCs also display fragments of the body's own proteins to T cells, helping to train them to recognize and ignore healthy body cells, thus preventing autoimmune reactions.13
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