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In this video, we look at T lymphocytes and cellmediated immunity. First we explore the structure of T lymphocytes including the T cell receptor. We then look at the four situations where a body cell can express antigens on its surface that can interact with the T cell receptor. Finally, we explore the roles of T helper cells, cytotoxic T cells and T regulator cells in cellmediated immunity.

Image credits:

Male torso

https://commons.wikimedia.org/wiki/Fi...

Taken at City Studios in Stockholm (www.stockholmsfotografen.se), September 29, 2011, with assistance from KYO (The organisation of life models) in Stockholm. Both models have consented to the licence of the image, and its usage in Wikipedia. Image uploaded by Mikael Häggström, CC0, via Wikimedia Commons