1,351
edits
Changes
Jump to navigation
Jump to search
→Introduction
Within the blood and lymphoid organs the majority of [[Lymphocytes - WikiBlood#Helper CD4+|CD4+ T cells]] are antigen-naive T-cells. There is only a small proportion of memory T-cells.
Within the blood and lymphoid organs the majority of [[Lymphocytes - WikiBlood#Helper CD4+|CD4+ T cells]] are antigen-naive T-cells. There is only a small proportion of memory T-cells.
Naive T-cells have yet to encounter antigen and can only be activated by antigen presented by dendritic cells. After initial antigenic activation, naïve T-cells develop into an intermediate stage cell called the TH<sub>0</sub> cell which can then be activated by any antigen-presenting cell, e.g. Dendritic cell, [[Macrophages - WikiBlood|macrophage]] or [[Lymphocytes - WikiBlood#B cells|B-cell]].
Naive T-cells have yet to encounter antigen and can only be activated by antigen presented by dendritic cells. After initial antigenic activation, naïve T-cells develop into an intermediate stage cell called the TH<sub>0</sub> cell which can then be activated by any antigen-presenting cell, e.g. Dendritic cells, [[Macrophages - WikiBlood|macrophages]] or [[Lymphocytes - WikiBlood#B cells|B-cells]].
The TH<sub>0</sub> cells have the capacity to differentiate into TH<sub>1</sub> and TH<sub>2</sub> cells. The type of cell that develops depends on the antigen presenting cell. [[Macrophages - WikiBlood|Macrophages]] cause the TH<sub>0</sub> cell to develop into TH<sub>1</sub> cells caused by IL-12 production following [[Macrophages - WikiBlood|macrophage]]-antigen interaction. [[Lymphocytes - WikiBlood#B cells|B-cells]] cause the TH<sub>0</sub> cell to develop into TH<sub>2</sub> cells caused by IL-10 production following B-cell-antigen interaction. On antigenic stimulation the TH<sub>1</sub> or TH<sub>2</sub> cells become activated, undergo clonal expansion and secrete a range of different cytokines.
The TH<sub>0</sub> cells have the capacity to differentiate into TH<sub>1</sub> and TH<sub>2</sub> cells. The type of cell that develops depends on the antigen presenting cell. [[Macrophages - WikiBlood|Macrophages]] cause the TH<sub>0</sub> cell to develop into TH<sub>1</sub> cells caused by IL-12 production following [[Macrophages - WikiBlood|macrophage]]-antigen interaction. [[Lymphocytes - WikiBlood#B cells|B-cells]] cause the TH<sub>0</sub> cell to develop into TH<sub>2</sub> cells caused by IL-10 production following B-cell-antigen interaction. On antigenic stimulation the TH<sub>1</sub> or TH<sub>2</sub> cells become activated, undergo clonal expansion and secrete a range of different cytokines.