Innate Immunity Rui He ruihe@fudan.edu.cn Department of Immunology Shanghai Medical School Fudan University
Innate Immunity Rui He ruihe@fudan.edu.cn Department of Immunology Shanghai Medical School Fudan University
Components of Immunit Innate Immunity non-specific, also called natural or native immunity Adaptive Immunity specific, also called acquired immunity
Components of Immunity Innate Immunity: non-specific, also called natural or native immunity Adaptive Immunity: specific, also called acquired immunity
Features of Innate and Adaptive Immunity Innate Adaptive Characteristics specificity For structures shared by groups of For antigens of microbes and for nonmicrobial related microbes antigens Diversity Limited; germline-encoded Very large; receptors are produced by somatic recombination of gene segments Memory None Yes Nonreactivity toYes Yes Components Cellular and Skin, mucosal epithelia Lymphocytes in epithelia; antibodies secreted at chemical barriers antimicrobial chemicals epithelial surfaces Blood proteins Complement, others Antibodies Cells Phagocytes(macrophages, Lymphocytes neutrophils), natural killer cells
Features of Innate and Adaptive Immunity Innate Adaptive Characteristics Specificity For structures shared by groups of related microbes For antigens of microbes and for nonmicrobial antigens Diversity Limited; germline-encoded Very large; receptors are produced by somatic recombination of gene segments Memory None Yes Nonreactivity to self Yes Yes Components Cellular and chemical barriers Skin, mucosal epithelia; antimicrobial chemicals Lymphocytes in epithelia; antibodies secreted at epithelial surfaces Blood proteins Complement, others Antibodies Cells Phagocytes (macrophages, neutrophils), natural killer cells Lymphocytes
The physiologic function of immune system Defense against infectious microbes Innate Immunity: the early reactions Adaptive Immunity: the later responses
The physiologic function of immune system Innate Immunity: the early reactions Adaptive Immunity: the later responses Defense against infectious microbes
Scope o Innate immunity Adaptive immunity I B lymphocytes Epithelial Antibodies barriers Phagocytes Effector T cells T lymphocytes Complement NK cells Hours Days 6 12 4 Time after infection Abbas et al: Cellular and Molecular Immunology, Updated 6th Edition Copyright(@ 2009 by Saunders, an imprint of Elsevier, Inc. All rights reserved
Innate Immunity 口 FUNCTIONS 日 COMPONENTS u Innate immunity recognition u The influence on adaptive immunity
❑ FUNCTIONS ❑ COMPONENTS ❑ Innate immunity recognition ❑ The influence on adaptive immunity Innate Immunity
OVERVIEW The first line of defense against infection O An evolutionarily older defense strategy, found in al classes of plants and animals u preexist infection or exposure to foreign antigen u respond immediately after recognition of microbes O Respond in essentially the same way to repeated infection
OVERVIEW The first line of defense against infection ❑ An evolutionarily older defense strategy, found in all classes of plants and animals ❑ Preexist infection or exposure to foreign antigen ❑ Respond immediately after recognition of microbes ❑ Respond in essentially the same way to repeated infection
FUNCTIONS a Initial response to microbes to prevent infection with elimination of danger u Innate components also important in adaptive immunity u stimulates adaptive responses
❑ Initial response to microbes to prevent infection with elimination of danger ❑ Innate components also important in adaptive immunity ❑ Stimulates adaptive responses FUNCTIONS
Components of innate immune system Com ponents Principal Functions Epithe lial barriers Epithelial layers Prevent microbial entry Defensins Microbial killing intraepithelial Microbial killing lymphocytes Circulating effector cells Neutrophils Early phagocytosis and killing of microbes Macrophages Efficient phagocytosis and killing of microbes, secretion of cytokines that stimulate inflammation NK cells Lysis of infected cells, activation of macrophages Circulating effector proteins Complement Killing of microbes, opsonization of microbes, activation of leukocytes Mannose-binding lectin Opsonization of microbes, activation of complement(lectin (collectin) pathway) C-reactive protein Opsonization of microbes, activation of complement (pentraxin) Cytokines
Components of innate immune system Components Principal Functions Epithelial barriers Epithelial layers Prevent microbial entry Defensins Microbial killing Intraepithelial lymphocytes Microbial killing Circulating effector cells Neutrophils Early phagocytosis and killing of microbes Macrophages Efficient phagocytosis and killing of microbes, secretion of cytokines that stimulate inflammation NK cells Lysis of infected cells, activation of macrophages Circulating effector proteins Complement Killing of microbes, opsonization of microbes, activation of leukocytes Mannose-binding lectin (collectin) Opsonization of microbes, activation of complement (lectin pathway) C-reactive protein (pentraxin) Opsonization of microbes, activation of complement Cytokines
Epithelial barriers Physical barrier to infection Peptide Killing of microbesantibiotics by locally produced 叠→ antibiotics ⊙0 Intraepithelial Killing of microbes lymphocyte and infected cells by intraepithelial lymphocytes
Epithelial barriers