Cytokines

Question 1

Cytokines secreted by macrophages?

Answer 1

• IL1: fever, acute inflammation, activates endothelium to express adhesion molecules, induces chemokine secretion to recruit RBCs
• IL6: fever, stimulates production of acute-phase reactants
• IL8: Chemotactic for neutrophils
• IL12: Differentiates T cells into Th1 cells, activates NK cells
• TNFα: Activates endothelium, WBC recruitment, vascular leaks, cachexia in malignancy, maintains granulomas in TB, mediate sepsis

Question 2

Cytokines secreted by All T cells?

Answer 2

• IL2: Stimulates growth of helper, cytotoxic, and regulatory T cells, and NK cells
• IL3: Supports growth & differentiation of bone marrow stem cells. FUnctions like GM-CSF

Question 3

Cytokines secreted from Th1 cells?

Answer 3

Interferon-𝝲:

• Secreted by NK cells and T cells in response to antigen or IL-12 from macrophages. Stimulates macrophages to kill phagocytosed pathogens. Inhibits differentiation of Th2 cells.
• Also activates NK cells to kill virus-infected cells
• Increases MHC expression and antigen presentation by all cells

Question 4

Cytokines secreted from Th2 cells?

Answer 4

• IL4: Differentiation of T cells into Th2 cells, promotes growth of B cells, enhances class switching to IgE and IgG
• IL5: Promotes growth and differentiation of B cells, enhances class switching to IgA, Stimulates growth & differentiation of eosinophils
• IL10: Attenuates inflammatory response, decreases expression of MHC II and Th1 cytokines, Inhibits activated macrophages and dendritic cells, Secreted by regulatory T cells