Mucosal and Cutaneous Immunity(진행중)
Most human pathogens gain access to the body through attacks on its mucosal surfaces or by penetrating the outer layers of the skin.
The integrity of our mucosae and skin is thus the essential “thin red line” separating the vulnerable inner workings of our bodies from the majority of external assaults. In Chapter 3 we introduced the concepts of MALT (mucosa-associated lymphoid tissue) and SALT (skin-associated lymphoid tissue).
These arms of the immune system are responsible for what researchers working in this area call “mucosal” and “cutaneous” adaptive immune responses, respectively. The MALT and SALT are made up of diffuse collections of APCs and lymphocytes that can respond to injurious entities that make contact with the mucosae or skin.
These responses can be mounted without necessarily involving the draining lymph node. However, a systemic immune response with the potential to attack antigen throughout the body can be induced when antigen-bearing APCs of the MALT or SALT migrate to the local lymph node.
Naive T and B cells in the node are activated and generate effectors that fan out into the blood and lymphatics and eliminate antigen that has penetrated beyond the MALT or SALT. We will now discuss in depth how leukocytes are integrated with other elements of the mucosae and skin to provide immune defense at the body portals.