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Immunology

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B Cells and T Cells

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Th2 Cells

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Summary

T-Helper Type 2 (Th2) cells are a type of effector Helper T-cell with a variety of functions. Th2 cell differentiation and proliferation from naive Helper T-cells is induced by interleukin-4 (IL-4). Once activated, Th2 cells produce more IL-4, Interleukin-5 (IL-5), and Interleukin-10 (IL-10). IL-4 works in an autocrine fashion to stimulate the production of more Th2 cells, but it can also stimulate the production of IgE by B-cells. IL-5 works downstream to stimulate the production of IgA by B-cells, and also stimulates the proliferation and activation of eosinophils. IL-10 works to taper off the immune response to prevent collateral damage to normal tissue. Altogether, Th2 are effector T-cells, and their signalling products play important roles in parasite defense, mucosal immunity, and the shutting off of immune responses to prevent autoimmunity.

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