Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details...
-
Upload
posy-doyle -
Category
Documents
-
view
220 -
download
0
Transcript of Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details...
![Page 1: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/1.jpg)
Antigen Receptors of Lymphocytes
![Page 2: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/2.jpg)
Recognition: molecular patterns
Recognition : molecular details (antigenic determinants)
Innate immunity
Aquired immunity (T i B lymphocytes)
Genes: functional, germline encoded
Genes: functional after DNA recombination
Receptors for recognition
Distribution: non-clonal distribution (same receptor on all cells within a cell line and even on the different lineages)
Presence: multiple copies of the same receptor
Distribution: clonal (cells within one clone exhibites receptor of the same specificity)
Presence: multiple copies of different receptors
![Page 3: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/3.jpg)
Antigen Receptors of Lymphocytes - Similiarity
On the lymphocyte membrane
Membrane Ig Antigen presenting cell
Antibody (Immunoglobulin) T-cell receptor(TCR)
![Page 4: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/4.jpg)
Antigen Receptors of Lymphocytes - Similiarity
On the lymphocyte membraneMembers of the immunoglobulin superfamily (domain structure)
Ig domains
![Page 5: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/5.jpg)
Antigen Receptors of Lymphocytes - Similiarity
On the lymphocyte membraneMembers of the immunoglobulin superfamily (domain structure)Two different chains
![Page 6: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/6.jpg)
Antigen Receptors of Lymphocytes - Similiarity
On the lymphocyte membraneMembers of the immunoglobulin superfamily (domain structure)Two different chainsVariable domains in contact with antigen (encoded by recombined DNA)
![Page 7: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/7.jpg)
Antigen Receptors of Lymphocytes - Similiarity
On the lymphocyte membraneMembers of the immunoglobulin superfamily (domain structure)Two different chainsVariable domains in contact with antigen (encoded by recombined DNA) Associated signal transduction molecules
Activation motif
Disulphide bond
![Page 8: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/8.jpg)
Signal trasduction
T cell receptor (TCR)
Antigen presenting cell
Signal trasduction
Membrane Ig
Antibody (Immunoglobulin)
Antigen Receptors of Lymphocytes - Differences
Recognizes: Free and membrane antigens Protein, polysaccharide, lipid, DNA, RNAConformational and linear epitopes
Recognizes :Antigens on the other cell membranePeptides only (αβ TCR)Linear epitopes
![Page 9: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/9.jpg)
Antigen Receptors of Lymphocytes - Differences
Recognizes: Free and membrane antigens Protein, polysaccharide, lipid, DNA, RNAConformational and linear epitopesConsists of:4 polypeptide chains (2H and 2L)
Recognizes: Antigens on the other cell membranePeptides only (αβ TCR)Linear epitopesConsists of:2 polypeptide chains (αβ or γδ)
![Page 10: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/10.jpg)
Antibody structure
Membrane of the B-cell
![Page 11: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/11.jpg)
"for their discoveries concerning the chemical structure of antibodies"
Gerald M. Edelman Rodney R. Porter
Nobel prize for physiology and medicine 1972
![Page 12: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/12.jpg)
Antibody structure
Heavy chain
Light chain Light chain
Heavy chain
Disulphide bonds
Antigen binding sites
![Page 13: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/13.jpg)
Antibody structure – papain digestion
Hinge region PapainFab fragments
Fc fragment
Interaction with other participants in the immune Response (cells, complement)
Antigen bindingAntibody structure
![Page 14: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/14.jpg)
Antibody structure – pepsin digestion
Pepsin
F(ab)2 fragment
Antigen binding
![Page 15: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/15.jpg)
MHC groove
Anchoring amino acids
Contact amino acid
Peptide
Polymorphic partsof MHC molecule
T-cell receptor
![Page 16: Antigen Receptors of Lymphocytes. Recognition: molecular patterns Recognition : molecular details (antigenic determinants) Innate immunity Aquired immunity.](https://reader036.fdocuments.us/reader036/viewer/2022062314/56649f2b5503460f94c454b2/html5/thumbnails/16.jpg)
TCR• Co-receptor molecules (CD4/CD8)
required
BCR• Recognition without
requirement for co-receptor molecules
Peptide
T-cell receptor (TCR)Immunoglobulin (Ig)