Porth's Essentials of Pathophysiology, 4e

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Infection and Immunity

U N I T 4

TABLE 15-1 Cytokines of Innate and Adaptive Immunity Cytokines Source

Biologic Activity

Interleukin-1 (IL-1)

Macrophages, endothelial cells, some epithelial cells

Wide variety of biologic effects; activates endothelium in inflammation; induces fever and acute-phase response; stimulates neutrophil production Growth factor for activatedT cells; induces synthesis of other cytokines; activates cytotoxicT lymphocytes and NK cells Growth factor for progenitor hematopoietic cells Promotes growth and survival of  T, B, and mast cells; causesT H 2 cell differentiation; activates B cells and eosinophils and induces IgE-type responses Stimulates the liver to produce mediators of acute-phase inflammatory response; also induces proliferation of antibody-producing cells by the adaptive immune system Primary function in adaptive immunity; stimulates pre-B cells and thymocyte development and proliferation Primary function in adaptive immunity; chemoattracts neutrophils andT lymphocytes; regulates lymphocyte homing and neutrophil infiltration Inhibitor of activated macrophages and dendritic cells; decreases inflammation by inhibitingT H 1 cells and release of IL-12 from macrophages Enhances NK cell cytotoxicity in innate immunity; induces T H 1 cell differentiation in adaptive immunity Inhibit viral replication; activate NK cells; increase expression of MHC-I molecules on virus-infected cells Activates macrophages in both innate immune responses and adaptive cell-mediated immune responses; increases expression of MHC-I and -II and antigen processing and presentation Induces inflammation, fever, and acute-phase response; activates neutrophils and endothelial cells; kills cells through apoptosis Large family of structurally similar cytokines that stimulate leukocyte movement and regulate the migration of leukocytes from the blood to the tissues Promotes neutrophil, eosinophil, and monocyte maturation and growth; activates mature granulocytes Induces eosinophil growth and development Promotes growth and maturation of neutrophils consumed in inflammatory reactions Promotes growth and maturation of mononuclear phagocytes

Interleukin-2 (IL-2)

CD4 + , CD8 + T cells

Interleukin-3 (IL-3) Interleukin-4 (IL-4)

CD4 + T cells

CD4 + T H

2 cells, mast cells

Interleukin-5 (IL-5) Interleukin-6 (IL-6)

CD4 + T H

2 cells

Macrophages, endothelial cells, T lymphocytes

Interleukin-7 (IL-7)

Bone marrow stromal cells

Interleukin-8 (IL-8)

Macrophages, endothelial cells

Interleukin-10 (IL-10)

Macrophages, someT-helper cells

Interleukin-12 (IL-12)

Macrophages, dendritic cells

Type I interferons (IFN- α , IFN- β ) Interferon- γ (IFN- γ )

Macrophages, fibroblasts

NK cells, CD4 + and CD8 + T lymphocytes

Tumor necrosis factor- α (TNF- α )

Macrophages,T cells

Chemokines

Macrophages, endothelial cells, T lymphocytes

Granulocyte-monocyte CSF (GM-CSF) Granulocyte CSF (G-CSF)

T cells, macrophages, endothelial cells, fibroblasts Macrophages, fibroblasts, endothelial cells Macrophages, activatedT cells, endothelial cells

Monocyte CSF (M-CSF)

CSF, colony-stimulating factor; MHC, major histocompatibility complex; NK, natural killer;T H

1,T-helper type 1;T H

2,T-helper type 2.

the granulocyte-monocyte progenitor cells to produce monocytes, neutrophils, and dendritic cells; granulocyte colony-stimulating factor (G-CSF) specifically induces neutrophil proliferation; and macrophage colony-stim- ulating factor (M-CSF) directs the mononuclear phago- cyte progenitor. Other cytokines, including IL-3, IL-7, and IL-11, also influence hematopoiesis. Recombinant CSF molecules are currently being used to increase the success rates of bone marrow transplantations. The availability of recombinant CSFs and cytokines offers the possibility of several clinical therapies where stimu- lation or inhibition of the immune response or cell pro- duction is desirable.

SUMMARY CONCEPTS

■■ Immunity is the resistance to a disease that is provided by the immune system. Innate immunity, which is the first line of defense against microbial agents, can distinguish between self and nonself but not among specific pathogens. Adaptive immunity, which involves humoral and cell-mediated immune responses