Changes

===Response to Activation===

===Response to Activation===

 

The response of the T cells to obtaining Signals 1 and 2 is to express the receptor for the cytokine interleukin-2 (IL-2) and CD4+ T-cells secrete IL-2.  

* The response of the [[Lymphocytes#T cells|T cells]] to obtaining Signals 1 and 2 is:

The final trigger for clonal expansion is the engagement of IL-2R with IL-2 from any activated CD4+ T-cell. IL-2 produced by a CD4+ cell may also stimulate clonal expansion of the CD4+ cell.

** To express the receptor for the cytokine interleukin-2 (IL-2).

** In [[Lymphocytes#Helper CD4+|CD4+ T-cells]] only, the secretion of IL-2.  

* The final trigger for clonal expansion is the engagement of IL-2R with IL-2.

** The IL-2 can come from any activated CD4+ T-cell.

** IL-2 produced by a CD4+ cell may also stimulate clonal expansion of that cell.

==T-Helper Cell Function==

==T-Helper Cell Function==