Download 5. Cytokine

5. Cytokine
细胞因子
王家鑫，孟明
Department of Veterinary Immunology
College of Animal Science and Technology
Agricultural University of Hebei
1. General Properties of Cytokines
1.1 Cytokines are polypeptides produced by
immune cells (macrophages, mast cells,
dendritic cells, and T cells ) and non-immune
cells (epithelial cells, 上皮细胞) in response
to microbes and other antigens that mediate
and regulate immune response and
inflammation reactions.
• Cytokines are a group of intercellular signaling
peptides and glycoproteins.
• Cytokines not only regulate immune and
inflammatory responses, but also affect wound
healing（创伤愈合）, hematopoiesis,
angiogenesis（血管生成）, and many other
biologic processes.
1.2 Classification of cytokines
1.2.1 Interleukine(IL)，白介素. IL-1, IL-2,IL-12.
1.2.2 Tumor necrosis factor(TNF), 肿瘤坏死因子
TNF-α，TNF-β
1.2.3 Interferon(IFN), 干扰素. IFN-α, IFN-β, IFN-γ
1.2.4 Colony-stimulating factors(CSF), 集落刺激因子
Monocyte-CSF(M-CSF),
Granulocyte-monocyte CSF(GM-CSF)
1.2.5 Transforming growth factor(TGF), 转化生长因子
1.2.6 Chemokines，趋化因子. IL-8
1.3 Immunological effects of cytokines
♥.
The actions of cytokines are often Pleiotropic
(多效性)and Redundant（重叠性）
Pleiotropic means the ability of one cytokine
to act on different cell types.
Redundant refers to the property of multiple
cytokines having the same functional effects.
多效性
重叠性
协同性
拮抗性
♥. Cytokines often influence the synthesis
and actions of other cytokines.
♥. Cytokine actions may be local and systemic.
自分泌
内分泌
旁分泌
♥. Cytokines initiate their actions by binding to
specific membrane receptors on the target cells.
♥. External signals regulate the expression of
cytokine receptors and thus the responsiveness
of cells to cytokines.
♥. The cellular responses to most cytokines
consist of changes in gene expression in
target cells, resulting in the expression of
new functions and sometimes in the
proliferation of the target cells.
2. Functional Classification of Cytokines
• Mediators and regulators of innate immunity
These cytokines are produced mainly by
mononuclear phagocytes in response to
infectious agents.
• Mediators and regulators of adaptive immunity
Produced mainly by T cells in response to
specific recognition of antigens.
• Stimulators of hematopoiesis
Produced by bone marrow stromal cells,
leukocytes, and other cells.
3. Cytokine Receptors
• All cytokine receptors consist of one or more
transmembrane proteins whose extracellular
portions are responsible for cytokine binding and
whose cytoplasmic portions are responsible for
initiating intracellular signaling pathways.
• There are three major shared receptors in the
class I cytokine receptor family: the common
gamma chain (γc), gp130,and the common beta
chain (βc).
4. Cytokines That Mediate and
Regulate Innate Immunity
促炎因子
Bystander activation
IFN-α, IFNβ
脑垂体细胞
5. Cytokines That Mediate and
Regulate Adaptive Immunity
Interleukin-2 (IL-2) and its receptor
Biological effects of IL-2
6. Cytokines That Stimulate
Hematopoiesis
Thank You!
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MHC gene and MHC molecules