Presentation is loading. Please wait.

Presentation is loading. Please wait.

Imunoglobulins – structure and function Production of immunoglobulins

Similar presentations


Presentation on theme: "Imunoglobulins – structure and function Production of immunoglobulins"— Presentation transcript:

1 Imunoglobulins – structure and function Production of immunoglobulins
Imunoglobulins – structure and function Production of immunoglobulins Genetic determination of immunoglobulin production Clonal selection theory

2 Antigen and epitope

3

4

5

6

7 Molecule of IgG

8 Hypervaribale region of immunoglobulin molecule binds epitope of the antigen

9 Variable region of immunoglobulin molecule

10

11 VDJ Recombination Germline configuration D to J recombination
V segments D segments J segments Constant region exons D to J recombination V to DJ recombination transcription, splicing AAA Issembly Adapted from Janeway 2001

12 Isotype switching

13 Isotype switching

14 Clonal selection theory F.M. Burnet, 1957
During (mainly fetal) development immunocompetent cells of the immune system develop. Each sell is characterized by its own antigen specific receptor. Each cell reacts only with one concrete specific antigen. After exposure to autoantigen during fetal life autoreactive clones are eliminated ( „forbidden clones“). If a concrete cell recognizes its specific antigen, it is stimulated, proliferates and forms a clone = clonal selection. After repeated divisions the cell becomes a terminally differentiated cell, that does not proliferate and after some time dies. The cells of the clone that do not differentiate into the terminal stage become a memory cells which will quickly react after the second exposure to the antigen.

15 Clonal selection theory
Memory cells Elimination of autoreactive clones Blood and periperal lymphatic organs expansion antigen death death Effector cells

16 Activation and differentiation of B-lymphocytes
(clonal selection theory in B-lymphocyte development) Downloaded from: StudentConsult (on 18 July :29 AM) © 2005 Elsevier

17 Downloaded from: StudentConsult (on 18 July 2006 11:29 AM)
© 2005 Elsevier

18 Isotype The class or subclass of an immunoglobulin.
Antigenic determinats are on constant part of immunoglobulin molecule.

19 Idiotype An antigenic determinant on the variable region of a specific antibody.

20 Interaction idiotype-antiidiotype
Epitop Paratop antigen Antiidiotyp idiotyp Antibody Ab 1 Antibody Ab 2 Antibody Ab 3

21

22 IgG

23

24 Primoary and secondary antibody immune response
Secondary antibody response Primary antibody response IgM IgG First exporsure Serum antibody titers Weeks Second exposure to antigen

25 Downloaded from: StudentConsult (on 18 July 2006 11:29 AM)
© 2005 Elsevier

26 IgM on B-cell membrane

27 Expression of surface immunoglobulins on B-cells

28

29 Formation of Secretory IgA
Downloaded from: StudentConsult (on 20 July :29 AM) © 2005 Elsevier

30 Affinity: The strength of the binding between a single site of an antibody (one variable region) and an epitope. Avidity: The overall strength of interaction between and antibody and antigen. The avidity depends on affinity and the valency of interactions.

31 Antibody affinity

32 Affinity and avidity IgA IgG IgM

33 Biological functions of immunoglobulin molecules
Activation of complement system (IgG, IgM) Opsonization (particularly IgG) Neutralization of antigens (IgG, IgA, IgM) Adherence interference (IgA, IgG) Antibody dependent cellular cytotoxicity (ADCC) Agglutation, precipitation (IgG, IgM) Mast cells degranulation (IgE) Transport through placenta (IgG) Imunoregulation (mainly IgG)

34 Antibody dependent cellular cytotoxicity (ADCC)
Virus-infected Cell IgG Fab Epitope Fc Fc receptor perforin granzyne NK Cell


Download ppt "Imunoglobulins – structure and function Production of immunoglobulins"

Similar presentations


Ads by Google