Professional antigen presenting cells (APCs) are immune cells that specialize in presenting an antigen to a T-cell. The main types of professional APCs are dendritic cells (DC), macrophages, and B cells. A professional APC takes up an antigen, processes it, and returns part of it to its surface, along with a class II major histocompatibility complex (MHC). The T-cell is activated when it interacts
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