Presentation made by using Interactive Physiology 10 and some books, some pictures from Ryan Medical Microbiology

1. ANTIBODIES
A N AT O L I Y T I M O F E E V
NOVI SAD
2012

2. WHAT DID YOU EXPECT?

3. TERMINS IN USE
• ANTIGEN – three-dimensional protein molecule on the
surface of pathogen
• PATHOGEN – disease causing agent
• ANTIBODY – protein molecule, that is produced by
immune system

4. ANTIBODIE ARE
Globuline proteins
Immunoglobulines
Gamma – globulines (𝞬 )

5. IMMUNOGLOBULINE STRUCTURE

6. IMMUNOGLOBULINES ARE
GLUCTOPROTEINS
Made up of
L (light)
H (heavy) chains
Weight because of
molecular mass
L = ± 25000
H = 50000 ± 70000
IgG=2H+2L chains

7. LIKE A LEGO! IS NOT IT?

8. 2 HEAVY

9. 2 HEAVY+ 2 LIGHT

10. !!!!+DISULFIDE BOND!!!!

11. L AND H PARTS HAVE VARIABLE AND
CONSTANT CHAINS

12. FAB- AND FC- FRAGMENTS
Comment
Fab sites bind antigen(fragment antigen bidning)
Fc fragment recognized by complement, phagocytes (fragment constant)

13. ANTIBODY MOLECULE IS SYMMETRICAL
• Both heavy chairs are identical
• Both light chairs are identical
Would quickly fall apart because it
is only loosly connected by
disulfide bonds.

14. CAN BE
•Bound to B cells as
receptor
•Secreted into plasma,
like “freelancers”

15. IMMUNOGLOBULINE CLASSES
IgG
IgA IgM
IgD IgE

16. MNEMONIC RULE

17. TOTAL AMOUNT OF IMMUNOGLOBULIN
IgM IgD In serum
9.072% 0.202% IgE
0.004%
IgA
15.120%
IgG
75.602%

18. IgG
H2L2(FORMLE)
•IgG1 – 65%
IgG2
IgG3
IgG4
/according to H chain and S-bond location

19. CHARACTERISTIC OF IgG
• Most abundant
• Predominant in secondary response
• Can cross the placenta
• Opsonizes (enhance phagocytosis)
• Transfer

20. IgA 2*(H2L2)+J+s.c.
J – means Joining
chair, what is needed for
connecting of 2 Fc –
fragments
+ secretory component

21. MAIN IMMUNOGLOBULIN IN
SECRETIONS IgA
•Saliva
•Tears
•Respiratory
•Intestinal
•Genital

22. IgA
Secretory component is
a polypeptide
synthesized by epithelial
cells that provide for IgA
passage to the mucosal
Surface>
Prevent attachment

23. IgM 5*H2L2+J
• Earlier produced in primary response
• Pentamer
• Agglutination(most efficient)
• Highest avidity
• First component of compliment

25. 10 BINDING SITES

26. HAS NO KNOWN A.B. FUNCTION

27. IgE
• Medicates immediate hypersensitivity >
anaphylactic reaction
• Defense against parasites
• Does not fix compliment

28. Property IgG IgA IgM IgD IgE
Serum 1000 200 120 3 0,05
[mg/dL]
Sedimention coefficient 7S 7S/11S 19S 7S 8S
MW(*1000) 150 170-400 900 180 190
Struture -mer Mono- Mono-/di- Mono- Mono- Mono-
/penta-
H chain symbol γ α μ δ Ε
Compliment ficsation + - + - -
Transplacental passage + - - ? -
Mediation of allergic reaction - - - - +
Found in secretions - + - - -
Opsonization + - - - -
Antigen receptors of B cells - - + ? -
Polemeric form contain - + + - -
J-chains

29. ISOTYPES
• Greek: Isos – equal
”We are different, but we are same”
Amino acidic differences in constant regions of
antibodies, according to it we have:
IgG(1-4)/IgA(1-2)/IgM/IgD/IgE
All people have it, but each of antigen has own specific
structure and functions, same for all humans.

30. ALLOTYPE
• Greek: Allos – other
“ We are same, but we are different “
Antigenic features of antibodies that vary among
individuals. Different alleles = different L and H chains.
𝞬 H chain contein an allotype called Gm(gamma) which
can differ to one- or two-amino-acids.
k L chains are called Inv(individual, patients name)

31. IDIOTYPES
• Greek: Idios – own
“We are same, but our difference inside of us”
Antigenic determinants formed by the specific amino acids
in the hyper variable regions.
+ Secondary response against cross-reacting agents
-Autoimmune diseases
allergy, anaphylaxis, asthma, transfusion
reactions, rheumatoid arthritis, and type I diabetes.

32. HUMORAL IMMUNITY
Humoral means antibody- mediated immunity.
Directed against:
• Toxin-induced diseases
• Infections
(virulence due to polysaccharide capsule)
• Certain viral infections
• Systemic
• Involves B and T lymphocytes
• Specific
• Has memory

33. CLASSIFICATION

35. THE PRIMARY RESPONSE
• First contact with antigen
• Long lag period (7-10 days)
• First antibodies are IgM 7 day
• Constant increase of antibody concentration
• Followed antibodies IgG/IgA production
• Elimination of alien
• Decrease of antibody concentration (35 day)
• !Keeping of some memory cells!

36. THE SECONDARY RESPONSE
• Contact of B- memory cells with same
or cross-reacting alient
• Rapid antibody response( lag period 3-5
days)
• Totally higher increase of antibodies
amount
• Longer period of decreasing of antibodies
concentration (of IgG)

37. DIFFERENCES IN CONCENTATION

38. MULTIPLE ANTIGENS
• When two or ore antigens are presented at the same
time, organism produces antibodies to each of them.
Therefor it is possible to use complex vaccines and
immunization got possible.
• DPT(diphtheria, pertussis, tetanus)
• MMR(measles, mumps, rubella)

39. FUNCTION OF ANTIBODIES
• Protection against inflectional Agents
• Protection against agent products
• Neutralization of toxins
• Neutralization of viruses
• Opsonize microorganisms*
*making of foreign cell more susceptible(available) for phagocytosis

41. FUNCTIONS (MNEMONIC RULE)

42. THANK YOU FOR ATTENTION
Do you have any questions?
I am ready to answer them according to my competition.