From Wikipedia, a free encyclopedia written in simple English for easy reading.
	    
	    	    	    
	    
| Description | The T lymphocyte activation pathway is triggered when a T cell encounters its cognate antigen, coupled to an MHC molecule, on the surface of an infected cell or a phagocyte. T cells contribute to immune defenses in two major ways: some direct and regulate immune responses; others directly attack infected or cancerous cells. | 
| Source | The Immune System (pdf) | 
| Date | NIH Publication No. 03–5423, September 2003 (modifications: September 4, 2006) | 
| Author | Template drawing and caption text from "The Immune System", any modifcations, made by myself are released into the public domain. | 
| Permission | Original work of the US Federal Government - public domain | 
|  | This image has been released into the public domain by its author, DO11.10. This applies worldwide. 
 In some countries this may not be legally possible; if so:DO11.10 grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
 | 
Links
The following pages link to this file: