浙江大学医学院：《免疫学 Immunology》课程教学资源（PPT课件）抗原 Antigen

Lecture 2 Antigen Zhijian Cai, Ph. D Institute of immunology ZJU

Antigen Zhijian Cai, Ph.D Institute of immunology, ZJU Lecture 2

1. Introduction 2. Antigenicity and specificit 3. Requirements for immunogenicity 4. Types of antigens 5. Superantigen immunological adjuvants and mItogen

1. Introduction 2. Antigenicity and specificity 3. Requirements for immunogenicity 4. Types of antigens 5. Superantigen ,immunological adjuvants and mitogen

Introduction 1.Antigen(Ag)-a substance that induces a specific immune response and can specifically bind to antibodies and effect t and b cells Alternative name-lmmunogen 2. Property of Ag- immunogenicity and antigenicity Complete Ag has immunogenicity and antigenicity

Introduction 1.Antigen (Ag) – A substance that induces a specific immune response and can specifically bind to antibodies and effect T and B cells. Alternative name - Immunogen 2.Property of Ag - immunogenicity and antigenicity Complete Ag has immunogenicity and antigenicity

Introduction 3. Hapten -a substance that is non- immunogenic but which can react with the products of a specific immune response. Haptens are small molecules which could never induce an immune response when administered by themselves but which can when coupled to a carrier molecule Haptens have the property of antigenicity but not immunogenicity 4. Tolerogen, allergen

Introduction 3.Hapten - A substance that is non-immunogenic but which can react with the products of a specific immune response. Haptens are small molecules which could never induce an immune response when administered by themselves but which can when coupled to a carrier molecule. Haptens have the property of antigenicity but not immunogenicity. 4. Tolerogen,allergen

Antigenicity and specificity Antigenicity The ability of a compound to bind with antibodies or with cells of the immune system This binding is highly specific

Antigenicity and specificity * Antigenicity The ability of a compound to bind with antibodies or with cells of the immune system. This binding is highly specific

Antigenicity and specificity 米 specificity 1. Antigenic determinant(epitope) the portion of the antigen that binds specifically with the binding site of an antibody or a receptor on a lymphocyte the size of an epitope is approximately equivalent to 5-7 amino acids

Antigenicity and specificity * specificity 1. Antigenic determinant (epitope) - the portion of the antigen that binds specifically with the binding site of an antibody or a receptor on a lymphocyte. - the size of an epitope is approximately equivalent to 5-7 amino acids

Antigenicity and specificity description example One epitope haptens Many epitopes of the same polysaccharides specificity Many epitopes of proteins different specificity Reprensentation of some possible antigenic structures

Antigenicity and specificity description example One epitope haptens Many epitopes of the same specificity polysaccharides Many epitopes of different specificity proteins Reprensentation of some possible antigenic structures

Antigenicity and specificity 2. structure of epitopes conformational determinant sequential or linear determinant c02 Intact prot 0 B cell epitope: 1, 2. linear epitopes; 3. conformational epitop o Tcell epitope: 4, 5. linear epitopes (presented by MHC molecules)

Antigenicity and specificity 2.structure of epitopes conformational determinant sequential or linear determinant

3. Epitopes recognized by B cells Epitopes recognized by T cells B cell epitope Antigenic peptide Degradation T cell epitope T cell epitope Natural protein B cell epitope and T cell epitope 76

3. Epitopes recognized by B cells Epitopes recognized by T cells B cell epitope T cell epitope Degradation Natural protein Antigenic peptide T cell epitope B cell epitope and T cell epitope

4 5 2 degradation 02 Intact protein protein fragments O B cell epitope: 1, 2. linear epitopes; 3. conformational epitope T cell epitope: 4, 5. linear epitopes(presented by MHC molecules) T and b cell epitopes in a protein antigen y

Antigen T and B cell epitopes in a protein antigen