The T Cell Receptor Only Recognizes Antigen in the Presence of Antigen
Presenting Cells. Abbas- Cellular and Molecular Immunology ...
Lecture 3: Antigen Recognition by T lymphocytes
Questions to Consider How do B cells and T cells see antigen? How does a T cells distinguish between
whether a foreign antigen is being presented to recruit help or because the cell is infected? Why do some T cells kill and others provide help?
Phagocytosis by Macrophages
Antigen Presenting Cells
Activation of Macrophages Permits Elimination of Mycobacterium Infection
Changes Exhibited by an Activated Macrophage
Development of a Secondary Amplified Response
T-cell Activation of Macrophages
Transfer of Which Cells Will Protect This Mouse From TB?
Activated monocytes T cells B cells
T-cell Activation of Macrophages Permits Killing of Phagocytosed Pathogens
How does the T cell know that the macrophage is infected with TB?
B Cells and T Cells Use Different Antigen-specific Receptors
T Cell Receptor Gene
Genetic Rearrangement Generates T Cell Receptor Diversity
Development of a Secondary Amplified Response
T Cells and B Cells Recognize Antigen Differently
Secondary Immune Response Primary Immunization
Secondary Ag Challenge
Native Protein
Native Protein
+
+
Denatured Protein
Native Protein
-
+
Denatured Protein Denatured Protein
-
+
+
+
Native Protein Denatured Protein
B Cell Response T Cell Response
The T Cell Receptor Only Recognizes Antigen in the Presence of Antigen Presenting Cells
Abbas- Cellular and Molecular Immunology
Antigen Must Be Processed to Peptides to be Recognized by the T Cell Receptor
Abbas- Cellular and Molecular Immunology
Antibody and T Cell Receptors Recognize Different Antigenic Contexts B Cells use the Immunoglobulin Molecule to recognize 3D structures of the native molecules. T Cells use the T cell receptor to recognize primary structures.
While the Majority of MHC-expressed Peptides are Self Self-reactive T Cells Are Not Present in the Periphery
Abbas- Cellular and Molecular Immunology
Two Different Types of MHC Molecules Are Capable of Presenting Peptides to T Cells
Divergent Cellular Expression of Class I and Class II MHC Molecules
Peripheral T Cells Express Either CD4 or CD8 Molecules
TCR Interaction With APCs Is Limited by CD4 or CD8 to Either MHC Class I or II, Respectively
Functional Implication of CD4 or CD8 Restricted Recognition of Class I or Class II MHC Molecules
Abbas- Cellular and Molecular Immunology
MHC Class I Molecules Only Present Peptides Derived From Endogenous Proteins
Cells Expressing Foreign Peptides Recognized by Cytotoxic CD8+ T Cells Are Killed
Antigen Presenting Cells
B Cells
Monocytes
MHC Class II Molecules Present Only Peptides Derived From Exogenous Proteins
CD4+ T Cells Stimulate Cells Expressing Foreign Peptides That They Recognize
B Cells Present Peptides Derived From Proteins Recognized by Surface Antibody
Correlation of Pathogen Location, MHC Presentation and T Cell Effector Function
NATURE |VOL 391 | 22 JANUARY 1998
Natural Killer (NK) Cells Prevent Evasion of CTL Immunity by Downregulation of MHC Class I MHC Molecules
Killer inhibitory receptors- KIR interact with MHC and prevent the NK cells from killing target cells
HIV Can Evade This Immune Response Too
Questions to Consider How do B cells and T cells see antigen? How does a T cells distinguish between
whether a foreign antigen is being presented to recruit help or because the cell is infected? Why do some T cells kill and others provide help?
