Changes

==Helper CD4+==

==Helper CD4+==

<p>These T cells express the marker CD4 and are categorised into two groups, Th1 and Th2, which are distinguished by the cytokines they produce. T helper cells recognise antigens bound to MHC II complex.

<p>These T cells express the marker CD4 and are categorised into two groups, Th1 and Th2, which are distinguished by the cytokines they produce. T helper cells recognise antigens bound to MHC II complexes.

*Th1 cells produce Il-2, IFN-γ and TNF-α  

*Th1 cells produce Il-2, IFN-γ and TNF-α  

*Th2 cells produce Il-4, Il-5, Il-10 and Il-13  

*Th2 cells produce Il-4, Il-5, Il-10 and Il-13  

Th1 cells interact with CD8⁺, NK and dendritic cells and Th2 cells interact with B cells. Th1 cells are involved with the control of intracellular pathogens and Th2 cells extracellular pathogens. Il-2 produced by Th1 cells stimulates further proliferation of CD4⁺ cells.</p>

Th1 cells interact with CD8⁺, NK and dendritic cells and Th2 cells interact with B cells. Th1 cells are involved with the control of intracellular pathogens and Th2 cells extracellular pathogens. Il-2 produced by Th1 cells stimulates further proliferation of CD4⁺ cells.</p>

<p>Th0 populations are CD4⁺ cells that have yet to differentiate into Th1 or Th2 cells and they secrete Il-2, IL-4, Il-5, IFN-γ. In the presence of Il-4 they develop into Th2 cells while in the presence of Il-12 they develop into Th1 cells. In the abscence of Il-12 Th1 cells will change into Th2 cells.</p>

<p>Th0 populations are CD4⁺ cells that have yet to differentiate into Th1 or Th2 cells and they secrete Il-2, IL-4, Il-5, IFN-γ. In the presence of Il-4 they develop into Th2 cells while in the presence of Il-2 they develop into Th1 cells. In the abscence of Il-2 Th1 cells will change into Th2 cells.</p>

<p>Th1 cells have two populations. One that secretes IFN-γ and is short lived, and the other that doesn’t secrete IFN-γ and is long lived. The IFN-γ^- cells are termed memory T cells (This relationship is not the case for Il-4⁺ and Il-4^- Th2 cells).</p>

<p>Th1 cells have two populations; one that secretes IFN-γ and is short lived, and the other that doesn’t secrete IFN-γ and is long lived. The IFN-γ^- cells are termed '''memory T cells'''</p>

<p>For more information on T helper cells click [[T cell differentiation#TH1 Cells|here]]

==Cytotoxic CD8⁺==

==Cytotoxic CD8⁺==