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Adaptive Immune System - Overview (view source)
Revision as of 13:14, 18 May 2012
, 13:14, 18 May 2012→Cellular response: Proliferation and Differentiation
Once [[Lymphocytes#T Cells|T cells]] recognise antigen presence in the tissues, they go into action. Their first response is always to recruit help, which is accomplished by returning to the nearest [[Lymph Nodes - Anatomy & Physiology|lymph node]] to carry out clonal expansion. Daughter [[Lymphocytes#T Cells|T cells]] are created with identical TCRs in order to recognise the identified antigen. These daughter cells are then returned to the circulation via the efferent lymph.
Once [[Lymphocytes#T Cells|T cells]] recognise antigen presence in the tissues, they go into action. Their first response is always to recruit help, which is accomplished by returning to the nearest [[Lymph Nodes - Anatomy & Physiology|lymph node]] to carry out clonal expansion. Daughter [[Lymphocytes#T Cells|T cells]] are created with identical TCRs in order to recognise the identified antigen. These daughter cells are then returned to the circulation via the efferent lymph.
[[Lymphocytes#T Cells|T cells]] can differentiate three different ways, based on their Cluster of Differentiation (CD) number. All [[Lymphocytes#T Cells|T cells]] are CD3+, and naive circulating [[Lymphocytes#T Cells|T cells]] will differentiate upon interaction with antigen to become either [[Lymphocytes#Cytotoxic CD8+|'''CD8+ (cytotoxic)''']] or [[Lymphocytes#Helper CD4+|'''CD4+ (helper)''']] [[Lymphocytes#T Cells|T cells]]. [[Lymphocytes#Helper CD4+|CD4+ T-cells]] will initially become CD4-TH<sub>0</sub> cells, and must differentiate to [[T cell differentiation#TH1 Cells|TH<sub>1</sub>]] or [[T cell differentiation#TH2 Cells|TH<sub>2</sub>]] depending on the whim of the adaptive response. TH<sub>1</sub> and TH<sub>2</sub> cells carry out different types of responses: TH<sub>1</sub> is responsible for enhancing the [[Macrophages|macrophage]] response, whereas TH<sub>2</sub> cells enhance the [[Lymphocytes#B Cells|B cell]] antibody production. Typically, animals produce a balanced response of TH<sub>1</sub> and TH<sub>2</sub> cells, though this can lead to pathology, as can a skewed response, depending on the nature of the foreign organism. For more on [[Lymphocytes#T Cells|T cell]] differentiation, see [[T cell differentiation|here]].
[[Lymphocytes#T Cells|T cells]] can differentiate three different ways, based on their Cluster of Differentiation (CD) number. All [[Lymphocytes#T Cells|T cells]] are CD3+, and naive circulating [[Lymphocytes#T Cells|T cells]] will differentiate upon interaction with antigen to become either [[Lymphocytes#Cytotoxic CD8+|'''CD8+ (cytotoxic)''']] or [[Lymphocytes#Helper CD4+|'''CD4+ (helper)''']] [[Lymphocytes#T Cells|T cells]]. [[Lymphocytes#Helper CD4+|CD4+ T-cells]] will initially become CD4-T<sub>H</sub>0 cells, and must differentiate to [[T cell differentiation#TH1 Cells|T<sub>H</sub>1]], [[T cell differentiation#TH2 Cells|T<sub>H</sub>2]] or [[T cell differentiation#TH17 Cells|T<sub>H</sub>17]] cells depending on the whim of the adaptive response. T<sub>H</sub>1, T<sub>H</sub>2 and T<sub>H</sub>17 cells carry out different types of responses: T<sub>H</sub>1 is responsible for enhancing the [[Macrophages|macrophage]] response, whereas T<sub>H</sub>2 cells enhance the [[Lymphocytes#B Cells|B cell]] antibody production, and T<sub>H</sub>17 cells enhance the innate immune response through increased granulocyte trafficking. Typically, animals produce a balanced response of TH<sub>1</sub> and TH<sub>2</sub> cells, though this can lead to pathology, as can a skewed response, depending on the nature of the foreign organism. For more on [[Lymphocytes#T Cells|T cell]] differentiation, see [[T cell differentiation|here]].
*''[[Lymphocytes#B Cells|B cell]] response''
*''[[Lymphocytes#B Cells|B cell]] response''